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2296
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1
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2 /* pngwrite.c - general routines to write a PNG file
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3 *
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4 * Last changed in libpng 1.6.10 [March 6, 2014]
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5 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
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6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
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7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
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8 *
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9 * This code is released under the libpng license.
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10 * For conditions of distribution and use, see the disclaimer
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11 * and license in png.h
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12 */
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13
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14 #include "pngpriv.h"
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15 #if defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)
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16 # include <errno.h>
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17 #endif
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18
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19 #ifdef PNG_WRITE_SUPPORTED
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20
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21 #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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22 /* Write out all the unknown chunks for the current given location */
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23 static void
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24 write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
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25 unsigned int where)
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26 {
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27 if (info_ptr->unknown_chunks_num)
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28 {
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29 png_const_unknown_chunkp up;
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30
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31 png_debug(5, "writing extra chunks");
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32
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33 for (up = info_ptr->unknown_chunks;
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34 up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
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35 ++up)
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36 if (up->location & where)
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37 {
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38 /* If per-chunk unknown chunk handling is enabled use it, otherwise
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39 * just write the chunks the application has set.
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40 */
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41 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
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42 int keep = png_handle_as_unknown(png_ptr, up->name);
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43
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44 /* NOTE: this code is radically different from the read side in the
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45 * matter of handling an ancillary unknown chunk. In the read side
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46 * the default behavior is to discard it, in the code below the default
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47 * behavior is to write it. Critical chunks are, however, only
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48 * written if explicitly listed or if the default is set to write all
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49 * unknown chunks.
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50 *
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51 * The default handling is also slightly weird - it is not possible to
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52 * stop the writing of all unsafe-to-copy chunks!
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53 *
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54 * TODO: REVIEW: this would seem to be a bug.
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55 */
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56 if (keep != PNG_HANDLE_CHUNK_NEVER &&
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57 ((up->name[3] & 0x20) /* safe-to-copy overrides everything */ ||
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58 keep == PNG_HANDLE_CHUNK_ALWAYS ||
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59 (keep == PNG_HANDLE_CHUNK_AS_DEFAULT &&
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60 png_ptr->unknown_default == PNG_HANDLE_CHUNK_ALWAYS)))
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61 #endif
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62 {
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63 /* TODO: review, what is wrong with a zero length unknown chunk? */
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64 if (up->size == 0)
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65 png_warning(png_ptr, "Writing zero-length unknown chunk");
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66
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67 png_write_chunk(png_ptr, up->name, up->data, up->size);
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68 }
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69 }
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70 }
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71 }
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72 #endif /* PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED */
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73
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74 /* Writes all the PNG information. This is the suggested way to use the
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75 * library. If you have a new chunk to add, make a function to write it,
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76 * and put it in the correct location here. If you want the chunk written
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77 * after the image data, put it in png_write_end(). I strongly encourage
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78 * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
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79 * the chunk, as that will keep the code from breaking if you want to just
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80 * write a plain PNG file. If you have long comments, I suggest writing
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81 * them in png_write_end(), and compressing them.
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82 */
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83 void PNGAPI
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84 png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
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85 {
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86 png_debug(1, "in png_write_info_before_PLTE");
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87
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88 if (png_ptr == NULL || info_ptr == NULL)
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89 return;
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90
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91 if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
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92 {
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93 /* Write PNG signature */
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94 png_write_sig(png_ptr);
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95
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96 #ifdef PNG_MNG_FEATURES_SUPPORTED
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97 if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \
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98 (png_ptr->mng_features_permitted))
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99 {
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100 png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
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101 png_ptr->mng_features_permitted = 0;
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102 }
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103 #endif
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104
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105 /* Write IHDR information. */
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106 png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
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107 info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
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108 info_ptr->filter_type,
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109 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
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110 info_ptr->interlace_type
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111 #else
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112 0
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113 #endif
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114 );
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115
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116 /* The rest of these check to see if the valid field has the appropriate
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117 * flag set, and if it does, writes the chunk.
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118 *
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119 * 1.6.0: COLORSPACE support controls the writing of these chunks too, and
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120 * the chunks will be written if the WRITE routine is there and information
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121 * is available in the COLORSPACE. (See png_colorspace_sync_info in png.c
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122 * for where the valid flags get set.)
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123 *
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124 * Under certain circumstances the colorspace can be invalidated without
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125 * syncing the info_struct 'valid' flags; this happens if libpng detects and
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126 * error and calls png_error while the color space is being set, yet the
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127 * application continues writing the PNG. So check the 'invalid' flag here
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128 * too.
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129 */
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130 #ifdef PNG_GAMMA_SUPPORTED
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131 # ifdef PNG_WRITE_gAMA_SUPPORTED
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132 if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
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133 (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) &&
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134 (info_ptr->valid & PNG_INFO_gAMA))
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135 png_write_gAMA_fixed(png_ptr, info_ptr->colorspace.gamma);
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136 # endif
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137 #endif
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138
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139 #ifdef PNG_COLORSPACE_SUPPORTED
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140 /* Write only one of sRGB or an ICC profile. If a profile was supplied
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141 * and it matches one of the known sRGB ones issue a warning.
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142 */
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143 # ifdef PNG_WRITE_iCCP_SUPPORTED
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144 if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
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145 (info_ptr->valid & PNG_INFO_iCCP))
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146 {
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147 # ifdef PNG_WRITE_sRGB_SUPPORTED
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148 if (info_ptr->valid & PNG_INFO_sRGB)
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149 png_app_warning(png_ptr,
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150 "profile matches sRGB but writing iCCP instead");
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151 # endif
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152
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153 png_write_iCCP(png_ptr, info_ptr->iccp_name,
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154 info_ptr->iccp_profile);
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155 }
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156 # ifdef PNG_WRITE_sRGB_SUPPORTED
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157 else
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158 # endif
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159 # endif
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160
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161 # ifdef PNG_WRITE_sRGB_SUPPORTED
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162 if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
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163 (info_ptr->valid & PNG_INFO_sRGB))
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164 png_write_sRGB(png_ptr, info_ptr->colorspace.rendering_intent);
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165 # endif /* WRITE_sRGB */
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166 #endif /* COLORSPACE */
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167
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168 #ifdef PNG_WRITE_sBIT_SUPPORTED
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169 if (info_ptr->valid & PNG_INFO_sBIT)
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170 png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
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171 #endif
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172
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173 #ifdef PNG_COLORSPACE_SUPPORTED
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174 # ifdef PNG_WRITE_cHRM_SUPPORTED
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175 if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
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176 (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) &&
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177 (info_ptr->valid & PNG_INFO_cHRM))
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178 png_write_cHRM_fixed(png_ptr, &info_ptr->colorspace.end_points_xy);
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179 # endif
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180 #endif
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181
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182 #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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183 write_unknown_chunks(png_ptr, info_ptr, PNG_HAVE_IHDR);
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184 #endif
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185
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186 png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
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187 }
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188 }
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189
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190 void PNGAPI
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191 png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
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192 {
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193 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
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194 int i;
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195 #endif
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196
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197 png_debug(1, "in png_write_info");
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198
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199 if (png_ptr == NULL || info_ptr == NULL)
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200 return;
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201
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202 png_write_info_before_PLTE(png_ptr, info_ptr);
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203
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204 if (info_ptr->valid & PNG_INFO_PLTE)
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205 png_write_PLTE(png_ptr, info_ptr->palette,
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206 (png_uint_32)info_ptr->num_palette);
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207
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208 else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
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209 png_error(png_ptr, "Valid palette required for paletted images");
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210
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211 #ifdef PNG_WRITE_tRNS_SUPPORTED
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212 if (info_ptr->valid & PNG_INFO_tRNS)
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213 {
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214 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
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215 /* Invert the alpha channel (in tRNS) */
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216 if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
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217 info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
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218 {
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219 int j;
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220 for (j = 0; j<(int)info_ptr->num_trans; j++)
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221 info_ptr->trans_alpha[j] =
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222 (png_byte)(255 - info_ptr->trans_alpha[j]);
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223 }
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224 #endif
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225 png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color),
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226 info_ptr->num_trans, info_ptr->color_type);
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227 }
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228 #endif
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229 #ifdef PNG_WRITE_bKGD_SUPPORTED
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230 if (info_ptr->valid & PNG_INFO_bKGD)
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231 png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
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232 #endif
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233
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234 #ifdef PNG_WRITE_hIST_SUPPORTED
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235 if (info_ptr->valid & PNG_INFO_hIST)
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236 png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
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237 #endif
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238
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239 #ifdef PNG_WRITE_oFFs_SUPPORTED
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240 if (info_ptr->valid & PNG_INFO_oFFs)
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241 png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
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242 info_ptr->offset_unit_type);
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243 #endif
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244
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245 #ifdef PNG_WRITE_pCAL_SUPPORTED
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246 if (info_ptr->valid & PNG_INFO_pCAL)
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247 png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
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248 info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
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249 info_ptr->pcal_units, info_ptr->pcal_params);
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250 #endif
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251
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252 #ifdef PNG_WRITE_sCAL_SUPPORTED
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253 if (info_ptr->valid & PNG_INFO_sCAL)
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254 png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
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255 info_ptr->scal_s_width, info_ptr->scal_s_height);
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256 #endif /* sCAL */
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257
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258 #ifdef PNG_WRITE_pHYs_SUPPORTED
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259 if (info_ptr->valid & PNG_INFO_pHYs)
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260 png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
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261 info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
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262 #endif /* pHYs */
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263
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264 #ifdef PNG_WRITE_tIME_SUPPORTED
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265 if (info_ptr->valid & PNG_INFO_tIME)
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266 {
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267 png_write_tIME(png_ptr, &(info_ptr->mod_time));
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268 png_ptr->mode |= PNG_WROTE_tIME;
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269 }
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270 #endif /* tIME */
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271
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272 #ifdef PNG_WRITE_sPLT_SUPPORTED
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273 if (info_ptr->valid & PNG_INFO_sPLT)
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274 for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
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275 png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
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276 #endif /* sPLT */
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277
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278 #ifdef PNG_WRITE_TEXT_SUPPORTED
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279 /* Check to see if we need to write text chunks */
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280 for (i = 0; i < info_ptr->num_text; i++)
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281 {
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282 png_debug2(2, "Writing header text chunk %d, type %d", i,
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283 info_ptr->text[i].compression);
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284 /* An internationalized chunk? */
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285 if (info_ptr->text[i].compression > 0)
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286 {
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287 #ifdef PNG_WRITE_iTXt_SUPPORTED
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288 /* Write international chunk */
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289 png_write_iTXt(png_ptr,
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290 info_ptr->text[i].compression,
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291 info_ptr->text[i].key,
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292 info_ptr->text[i].lang,
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293 info_ptr->text[i].lang_key,
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294 info_ptr->text[i].text);
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295 #else
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296 png_warning(png_ptr, "Unable to write international text");
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297 #endif
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298 /* Mark this chunk as written */
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299 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
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300 }
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301
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302 /* If we want a compressed text chunk */
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303 else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
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304 {
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305 #ifdef PNG_WRITE_zTXt_SUPPORTED
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306 /* Write compressed chunk */
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307 png_write_zTXt(png_ptr, info_ptr->text[i].key,
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308 info_ptr->text[i].text, 0,
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309 info_ptr->text[i].compression);
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310 #else
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311 png_warning(png_ptr, "Unable to write compressed text");
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312 #endif
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313 /* Mark this chunk as written */
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314 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
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315 }
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316
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317 else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
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318 {
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319 #ifdef PNG_WRITE_tEXt_SUPPORTED
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320 /* Write uncompressed chunk */
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321 png_write_tEXt(png_ptr, info_ptr->text[i].key,
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322 info_ptr->text[i].text,
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323 0);
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324 /* Mark this chunk as written */
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325 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
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326 #else
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327 /* Can't get here */
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328 png_warning(png_ptr, "Unable to write uncompressed text");
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329 #endif
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330 }
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331 }
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332 #endif /* tEXt */
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333
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334 #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
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335 write_unknown_chunks(png_ptr, info_ptr, PNG_HAVE_PLTE);
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336 #endif
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337 }
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338
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339 /* Writes the end of the PNG file. If you don't want to write comments or
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340 * time information, you can pass NULL for info. If you already wrote these
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341 * in png_write_info(), do not write them again here. If you have long
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342 * comments, I suggest writing them here, and compressing them.
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343 */
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344 void PNGAPI
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345 png_write_end(png_structrp png_ptr, png_inforp info_ptr)
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346 {
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347 png_debug(1, "in png_write_end");
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348
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349 if (png_ptr == NULL)
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350 return;
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351
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352 if (!(png_ptr->mode & PNG_HAVE_IDAT))
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353 png_error(png_ptr, "No IDATs written into file");
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354
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355 #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
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356 if (png_ptr->num_palette_max > png_ptr->num_palette)
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357 png_benign_error(png_ptr, "Wrote palette index exceeding num_palette");
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358 #endif
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359
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360 /* See if user wants us to write information chunks */
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361 if (info_ptr != NULL)
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362 {
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363 #ifdef PNG_WRITE_TEXT_SUPPORTED
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364 int i; /* local index variable */
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365 #endif
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366 #ifdef PNG_WRITE_tIME_SUPPORTED
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367 /* Check to see if user has supplied a time chunk */
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368 if ((info_ptr->valid & PNG_INFO_tIME) &&
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369 !(png_ptr->mode & PNG_WROTE_tIME))
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370 png_write_tIME(png_ptr, &(info_ptr->mod_time));
|
|
|
371
|
|
|
372 #endif
|
|
|
373 #ifdef PNG_WRITE_TEXT_SUPPORTED
|
|
|
374 /* Loop through comment chunks */
|
|
|
375 for (i = 0; i < info_ptr->num_text; i++)
|
|
|
376 {
|
|
|
377 png_debug2(2, "Writing trailer text chunk %d, type %d", i,
|
|
|
378 info_ptr->text[i].compression);
|
|
|
379 /* An internationalized chunk? */
|
|
|
380 if (info_ptr->text[i].compression > 0)
|
|
|
381 {
|
|
|
382 #ifdef PNG_WRITE_iTXt_SUPPORTED
|
|
|
383 /* Write international chunk */
|
|
|
384 png_write_iTXt(png_ptr,
|
|
|
385 info_ptr->text[i].compression,
|
|
|
386 info_ptr->text[i].key,
|
|
|
387 info_ptr->text[i].lang,
|
|
|
388 info_ptr->text[i].lang_key,
|
|
|
389 info_ptr->text[i].text);
|
|
|
390 #else
|
|
|
391 png_warning(png_ptr, "Unable to write international text");
|
|
|
392 #endif
|
|
|
393 /* Mark this chunk as written */
|
|
|
394 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
|
|
|
395 }
|
|
|
396
|
|
|
397 else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
|
|
|
398 {
|
|
|
399 #ifdef PNG_WRITE_zTXt_SUPPORTED
|
|
|
400 /* Write compressed chunk */
|
|
|
401 png_write_zTXt(png_ptr, info_ptr->text[i].key,
|
|
|
402 info_ptr->text[i].text, 0,
|
|
|
403 info_ptr->text[i].compression);
|
|
|
404 #else
|
|
|
405 png_warning(png_ptr, "Unable to write compressed text");
|
|
|
406 #endif
|
|
|
407 /* Mark this chunk as written */
|
|
|
408 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
|
|
|
409 }
|
|
|
410
|
|
|
411 else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
|
|
|
412 {
|
|
|
413 #ifdef PNG_WRITE_tEXt_SUPPORTED
|
|
|
414 /* Write uncompressed chunk */
|
|
|
415 png_write_tEXt(png_ptr, info_ptr->text[i].key,
|
|
|
416 info_ptr->text[i].text, 0);
|
|
|
417 #else
|
|
|
418 png_warning(png_ptr, "Unable to write uncompressed text");
|
|
|
419 #endif
|
|
|
420
|
|
|
421 /* Mark this chunk as written */
|
|
|
422 info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
|
|
|
423 }
|
|
|
424 }
|
|
|
425 #endif
|
|
|
426 #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
|
|
|
427 write_unknown_chunks(png_ptr, info_ptr, PNG_AFTER_IDAT);
|
|
|
428 #endif
|
|
|
429 }
|
|
|
430
|
|
|
431 png_ptr->mode |= PNG_AFTER_IDAT;
|
|
|
432
|
|
|
433 /* Write end of PNG file */
|
|
|
434 png_write_IEND(png_ptr);
|
|
|
435 /* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03,
|
|
|
436 * and restored again in libpng-1.2.30, may cause some applications that
|
|
|
437 * do not set png_ptr->output_flush_fn to crash. If your application
|
|
|
438 * experiences a problem, please try building libpng with
|
|
|
439 * PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to
|
|
|
440 * png-mng-implement at lists.sf.net .
|
|
|
441 */
|
|
|
442 #ifdef PNG_WRITE_FLUSH_SUPPORTED
|
|
|
443 # ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED
|
|
|
444 png_flush(png_ptr);
|
|
|
445 # endif
|
|
|
446 #endif
|
|
|
447 }
|
|
|
448
|
|
|
449 #ifdef PNG_CONVERT_tIME_SUPPORTED
|
|
|
450 void PNGAPI
|
|
|
451 png_convert_from_struct_tm(png_timep ptime, PNG_CONST struct tm * ttime)
|
|
|
452 {
|
|
|
453 png_debug(1, "in png_convert_from_struct_tm");
|
|
|
454
|
|
|
455 ptime->year = (png_uint_16)(1900 + ttime->tm_year);
|
|
|
456 ptime->month = (png_byte)(ttime->tm_mon + 1);
|
|
|
457 ptime->day = (png_byte)ttime->tm_mday;
|
|
|
458 ptime->hour = (png_byte)ttime->tm_hour;
|
|
|
459 ptime->minute = (png_byte)ttime->tm_min;
|
|
|
460 ptime->second = (png_byte)ttime->tm_sec;
|
|
|
461 }
|
|
|
462
|
|
|
463 void PNGAPI
|
|
|
464 png_convert_from_time_t(png_timep ptime, time_t ttime)
|
|
|
465 {
|
|
|
466 struct tm *tbuf;
|
|
|
467
|
|
|
468 png_debug(1, "in png_convert_from_time_t");
|
|
|
469
|
|
|
470 tbuf = gmtime(&ttime);
|
|
|
471 png_convert_from_struct_tm(ptime, tbuf);
|
|
|
472 }
|
|
|
473 #endif
|
|
|
474
|
|
|
475 /* Initialize png_ptr structure, and allocate any memory needed */
|
|
|
476 PNG_FUNCTION(png_structp,PNGAPI
|
|
|
477 png_create_write_struct,(png_const_charp user_png_ver, png_voidp error_ptr,
|
|
|
478 png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED)
|
|
|
479 {
|
|
|
480 #ifndef PNG_USER_MEM_SUPPORTED
|
|
|
481 png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr,
|
|
|
482 error_fn, warn_fn, NULL, NULL, NULL);
|
|
|
483 #else
|
|
|
484 return png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
|
|
|
485 warn_fn, NULL, NULL, NULL);
|
|
|
486 }
|
|
|
487
|
|
|
488 /* Alternate initialize png_ptr structure, and allocate any memory needed */
|
|
|
489 PNG_FUNCTION(png_structp,PNGAPI
|
|
|
490 png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
|
|
|
491 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
|
|
|
492 png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED)
|
|
|
493 {
|
|
|
494 png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr,
|
|
|
495 error_fn, warn_fn, mem_ptr, malloc_fn, free_fn);
|
|
|
496 #endif /* PNG_USER_MEM_SUPPORTED */
|
|
|
497 if (png_ptr != NULL)
|
|
|
498 {
|
|
|
499 /* Set the zlib control values to defaults; they can be overridden by the
|
|
|
500 * application after the struct has been created.
|
|
|
501 */
|
|
|
502 png_ptr->zbuffer_size = PNG_ZBUF_SIZE;
|
|
|
503
|
|
|
504 /* The 'zlib_strategy' setting is irrelevant because png_default_claim in
|
|
|
505 * pngwutil.c defaults it according to whether or not filters will be
|
|
|
506 * used, and ignores this setting.
|
|
|
507 */
|
|
|
508 png_ptr->zlib_strategy = PNG_Z_DEFAULT_STRATEGY;
|
|
|
509 png_ptr->zlib_level = PNG_Z_DEFAULT_COMPRESSION;
|
|
|
510 png_ptr->zlib_mem_level = 8;
|
|
|
511 png_ptr->zlib_window_bits = 15;
|
|
|
512 png_ptr->zlib_method = 8;
|
|
|
513
|
|
|
514 #ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
|
|
|
515 png_ptr->zlib_text_strategy = PNG_TEXT_Z_DEFAULT_STRATEGY;
|
|
|
516 png_ptr->zlib_text_level = PNG_TEXT_Z_DEFAULT_COMPRESSION;
|
|
|
517 png_ptr->zlib_text_mem_level = 8;
|
|
|
518 png_ptr->zlib_text_window_bits = 15;
|
|
|
519 png_ptr->zlib_text_method = 8;
|
|
|
520 #endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
|
|
|
521
|
|
|
522 /* This is a highly dubious configuration option; by default it is off,
|
|
|
523 * but it may be appropriate for private builds that are testing
|
|
|
524 * extensions not conformant to the current specification, or of
|
|
|
525 * applications that must not fail to write at all costs!
|
|
|
526 */
|
|
|
527 #ifdef PNG_BENIGN_WRITE_ERRORS_SUPPORTED
|
|
|
528 png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN;
|
|
|
529 /* In stable builds only warn if an application error can be completely
|
|
|
530 * handled.
|
|
|
531 */
|
|
|
532 #endif
|
|
|
533
|
|
|
534 /* App warnings are warnings in release (or release candidate) builds but
|
|
|
535 * are errors during development.
|
|
|
536 */
|
|
|
537 #if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
|
|
|
538 png_ptr->flags |= PNG_FLAG_APP_WARNINGS_WARN;
|
|
|
539 #endif
|
|
|
540
|
|
|
541 /* TODO: delay this, it can be done in png_init_io() (if the app doesn't
|
|
|
542 * do it itself) avoiding setting the default function if it is not
|
|
|
543 * required.
|
|
|
544 */
|
|
|
545 png_set_write_fn(png_ptr, NULL, NULL, NULL);
|
|
|
546 }
|
|
|
547
|
|
|
548 return png_ptr;
|
|
|
549 }
|
|
|
550
|
|
|
551
|
|
|
552 /* Write a few rows of image data. If the image is interlaced,
|
|
|
553 * either you will have to write the 7 sub images, or, if you
|
|
|
554 * have called png_set_interlace_handling(), you will have to
|
|
|
555 * "write" the image seven times.
|
|
|
556 */
|
|
|
557 void PNGAPI
|
|
|
558 png_write_rows(png_structrp png_ptr, png_bytepp row,
|
|
|
559 png_uint_32 num_rows)
|
|
|
560 {
|
|
|
561 png_uint_32 i; /* row counter */
|
|
|
562 png_bytepp rp; /* row pointer */
|
|
|
563
|
|
|
564 png_debug(1, "in png_write_rows");
|
|
|
565
|
|
|
566 if (png_ptr == NULL)
|
|
|
567 return;
|
|
|
568
|
|
|
569 /* Loop through the rows */
|
|
|
570 for (i = 0, rp = row; i < num_rows; i++, rp++)
|
|
|
571 {
|
|
|
572 png_write_row(png_ptr, *rp);
|
|
|
573 }
|
|
|
574 }
|
|
|
575
|
|
|
576 /* Write the image. You only need to call this function once, even
|
|
|
577 * if you are writing an interlaced image.
|
|
|
578 */
|
|
|
579 void PNGAPI
|
|
|
580 png_write_image(png_structrp png_ptr, png_bytepp image)
|
|
|
581 {
|
|
|
582 png_uint_32 i; /* row index */
|
|
|
583 int pass, num_pass; /* pass variables */
|
|
|
584 png_bytepp rp; /* points to current row */
|
|
|
585
|
|
|
586 if (png_ptr == NULL)
|
|
|
587 return;
|
|
|
588
|
|
|
589 png_debug(1, "in png_write_image");
|
|
|
590
|
|
|
591 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
|
|
|
592 /* Initialize interlace handling. If image is not interlaced,
|
|
|
593 * this will set pass to 1
|
|
|
594 */
|
|
|
595 num_pass = png_set_interlace_handling(png_ptr);
|
|
|
596 #else
|
|
|
597 num_pass = 1;
|
|
|
598 #endif
|
|
|
599 /* Loop through passes */
|
|
|
600 for (pass = 0; pass < num_pass; pass++)
|
|
|
601 {
|
|
|
602 /* Loop through image */
|
|
|
603 for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
|
|
|
604 {
|
|
|
605 png_write_row(png_ptr, *rp);
|
|
|
606 }
|
|
|
607 }
|
|
|
608 }
|
|
|
609
|
|
|
610 #ifdef PNG_MNG_FEATURES_SUPPORTED
|
|
|
611 /* Performs intrapixel differencing */
|
|
|
612 static void
|
|
|
613 png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
|
|
|
614 {
|
|
|
615 png_debug(1, "in png_do_write_intrapixel");
|
|
|
616
|
|
|
617 if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
|
|
|
618 {
|
|
|
619 int bytes_per_pixel;
|
|
|
620 png_uint_32 row_width = row_info->width;
|
|
|
621 if (row_info->bit_depth == 8)
|
|
|
622 {
|
|
|
623 png_bytep rp;
|
|
|
624 png_uint_32 i;
|
|
|
625
|
|
|
626 if (row_info->color_type == PNG_COLOR_TYPE_RGB)
|
|
|
627 bytes_per_pixel = 3;
|
|
|
628
|
|
|
629 else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
|
|
|
630 bytes_per_pixel = 4;
|
|
|
631
|
|
|
632 else
|
|
|
633 return;
|
|
|
634
|
|
|
635 for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
|
|
|
636 {
|
|
|
637 *(rp) = (png_byte)((*rp - *(rp + 1)) & 0xff);
|
|
|
638 *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff);
|
|
|
639 }
|
|
|
640 }
|
|
|
641
|
|
|
642 #ifdef PNG_WRITE_16BIT_SUPPORTED
|
|
|
643 else if (row_info->bit_depth == 16)
|
|
|
644 {
|
|
|
645 png_bytep rp;
|
|
|
646 png_uint_32 i;
|
|
|
647
|
|
|
648 if (row_info->color_type == PNG_COLOR_TYPE_RGB)
|
|
|
649 bytes_per_pixel = 6;
|
|
|
650
|
|
|
651 else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
|
|
|
652 bytes_per_pixel = 8;
|
|
|
653
|
|
|
654 else
|
|
|
655 return;
|
|
|
656
|
|
|
657 for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
|
|
|
658 {
|
|
|
659 png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1);
|
|
|
660 png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3);
|
|
|
661 png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5);
|
|
|
662 png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL);
|
|
|
663 png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL);
|
|
|
664 *(rp ) = (png_byte)((red >> 8) & 0xff);
|
|
|
665 *(rp + 1) = (png_byte)(red & 0xff);
|
|
|
666 *(rp + 4) = (png_byte)((blue >> 8) & 0xff);
|
|
|
667 *(rp + 5) = (png_byte)(blue & 0xff);
|
|
|
668 }
|
|
|
669 }
|
|
|
670 #endif /* PNG_WRITE_16BIT_SUPPORTED */
|
|
|
671 }
|
|
|
672 }
|
|
|
673 #endif /* PNG_MNG_FEATURES_SUPPORTED */
|
|
|
674
|
|
|
675 /* Called by user to write a row of image data */
|
|
|
676 void PNGAPI
|
|
|
677 png_write_row(png_structrp png_ptr, png_const_bytep row)
|
|
|
678 {
|
|
|
679 /* 1.5.6: moved from png_struct to be a local structure: */
|
|
|
680 png_row_info row_info;
|
|
|
681
|
|
|
682 if (png_ptr == NULL)
|
|
|
683 return;
|
|
|
684
|
|
|
685 png_debug2(1, "in png_write_row (row %u, pass %d)",
|
|
|
686 png_ptr->row_number, png_ptr->pass);
|
|
|
687
|
|
|
688 /* Initialize transformations and other stuff if first time */
|
|
|
689 if (png_ptr->row_number == 0 && png_ptr->pass == 0)
|
|
|
690 {
|
|
|
691 /* Make sure we wrote the header info */
|
|
|
692 if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
|
|
|
693 png_error(png_ptr,
|
|
|
694 "png_write_info was never called before png_write_row");
|
|
|
695
|
|
|
696 /* Check for transforms that have been set but were defined out */
|
|
|
697 #if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
|
|
|
698 if (png_ptr->transformations & PNG_INVERT_MONO)
|
|
|
699 png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined");
|
|
|
700 #endif
|
|
|
701
|
|
|
702 #if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
|
|
|
703 if (png_ptr->transformations & PNG_FILLER)
|
|
|
704 png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined");
|
|
|
705 #endif
|
|
|
706 #if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
|
|
|
707 defined(PNG_READ_PACKSWAP_SUPPORTED)
|
|
|
708 if (png_ptr->transformations & PNG_PACKSWAP)
|
|
|
709 png_warning(png_ptr,
|
|
|
710 "PNG_WRITE_PACKSWAP_SUPPORTED is not defined");
|
|
|
711 #endif
|
|
|
712
|
|
|
713 #if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
|
|
|
714 if (png_ptr->transformations & PNG_PACK)
|
|
|
715 png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined");
|
|
|
716 #endif
|
|
|
717
|
|
|
718 #if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
|
|
|
719 if (png_ptr->transformations & PNG_SHIFT)
|
|
|
720 png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined");
|
|
|
721 #endif
|
|
|
722
|
|
|
723 #if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
|
|
|
724 if (png_ptr->transformations & PNG_BGR)
|
|
|
725 png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined");
|
|
|
726 #endif
|
|
|
727
|
|
|
728 #if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
|
|
|
729 if (png_ptr->transformations & PNG_SWAP_BYTES)
|
|
|
730 png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined");
|
|
|
731 #endif
|
|
|
732
|
|
|
733 png_write_start_row(png_ptr);
|
|
|
734 }
|
|
|
735
|
|
|
736 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
|
|
|
737 /* If interlaced and not interested in row, return */
|
|
|
738 if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
|
|
|
739 {
|
|
|
740 switch (png_ptr->pass)
|
|
|
741 {
|
|
|
742 case 0:
|
|
|
743 if (png_ptr->row_number & 0x07)
|
|
|
744 {
|
|
|
745 png_write_finish_row(png_ptr);
|
|
|
746 return;
|
|
|
747 }
|
|
|
748 break;
|
|
|
749
|
|
|
750 case 1:
|
|
|
751 if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
|
|
|
752 {
|
|
|
753 png_write_finish_row(png_ptr);
|
|
|
754 return;
|
|
|
755 }
|
|
|
756 break;
|
|
|
757
|
|
|
758 case 2:
|
|
|
759 if ((png_ptr->row_number & 0x07) != 4)
|
|
|
760 {
|
|
|
761 png_write_finish_row(png_ptr);
|
|
|
762 return;
|
|
|
763 }
|
|
|
764 break;
|
|
|
765
|
|
|
766 case 3:
|
|
|
767 if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
|
|
|
768 {
|
|
|
769 png_write_finish_row(png_ptr);
|
|
|
770 return;
|
|
|
771 }
|
|
|
772 break;
|
|
|
773
|
|
|
774 case 4:
|
|
|
775 if ((png_ptr->row_number & 0x03) != 2)
|
|
|
776 {
|
|
|
777 png_write_finish_row(png_ptr);
|
|
|
778 return;
|
|
|
779 }
|
|
|
780 break;
|
|
|
781
|
|
|
782 case 5:
|
|
|
783 if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
|
|
|
784 {
|
|
|
785 png_write_finish_row(png_ptr);
|
|
|
786 return;
|
|
|
787 }
|
|
|
788 break;
|
|
|
789
|
|
|
790 case 6:
|
|
|
791 if (!(png_ptr->row_number & 0x01))
|
|
|
792 {
|
|
|
793 png_write_finish_row(png_ptr);
|
|
|
794 return;
|
|
|
795 }
|
|
|
796 break;
|
|
|
797
|
|
|
798 default: /* error: ignore it */
|
|
|
799 break;
|
|
|
800 }
|
|
|
801 }
|
|
|
802 #endif
|
|
|
803
|
|
|
804 /* Set up row info for transformations */
|
|
|
805 row_info.color_type = png_ptr->color_type;
|
|
|
806 row_info.width = png_ptr->usr_width;
|
|
|
807 row_info.channels = png_ptr->usr_channels;
|
|
|
808 row_info.bit_depth = png_ptr->usr_bit_depth;
|
|
|
809 row_info.pixel_depth = (png_byte)(row_info.bit_depth * row_info.channels);
|
|
|
810 row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width);
|
|
|
811
|
|
|
812 png_debug1(3, "row_info->color_type = %d", row_info.color_type);
|
|
|
813 png_debug1(3, "row_info->width = %u", row_info.width);
|
|
|
814 png_debug1(3, "row_info->channels = %d", row_info.channels);
|
|
|
815 png_debug1(3, "row_info->bit_depth = %d", row_info.bit_depth);
|
|
|
816 png_debug1(3, "row_info->pixel_depth = %d", row_info.pixel_depth);
|
|
|
817 png_debug1(3, "row_info->rowbytes = %lu", (unsigned long)row_info.rowbytes);
|
|
|
818
|
|
|
819 /* Copy user's row into buffer, leaving room for filter byte. */
|
|
|
820 memcpy(png_ptr->row_buf + 1, row, row_info.rowbytes);
|
|
|
821
|
|
|
822 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
|
|
|
823 /* Handle interlacing */
|
|
|
824 if (png_ptr->interlaced && png_ptr->pass < 6 &&
|
|
|
825 (png_ptr->transformations & PNG_INTERLACE))
|
|
|
826 {
|
|
|
827 png_do_write_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass);
|
|
|
828 /* This should always get caught above, but still ... */
|
|
|
829 if (!(row_info.width))
|
|
|
830 {
|
|
|
831 png_write_finish_row(png_ptr);
|
|
|
832 return;
|
|
|
833 }
|
|
|
834 }
|
|
|
835 #endif
|
|
|
836
|
|
|
837 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
|
|
|
838 /* Handle other transformations */
|
|
|
839 if (png_ptr->transformations)
|
|
|
840 png_do_write_transformations(png_ptr, &row_info);
|
|
|
841 #endif
|
|
|
842
|
|
|
843 /* At this point the row_info pixel depth must match the 'transformed' depth,
|
|
|
844 * which is also the output depth.
|
|
|
845 */
|
|
|
846 if (row_info.pixel_depth != png_ptr->pixel_depth ||
|
|
|
847 row_info.pixel_depth != png_ptr->transformed_pixel_depth)
|
|
|
848 png_error(png_ptr, "internal write transform logic error");
|
|
|
849
|
|
|
850 #ifdef PNG_MNG_FEATURES_SUPPORTED
|
|
|
851 /* Write filter_method 64 (intrapixel differencing) only if
|
|
|
852 * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
|
|
|
853 * 2. Libpng did not write a PNG signature (this filter_method is only
|
|
|
854 * used in PNG datastreams that are embedded in MNG datastreams) and
|
|
|
855 * 3. The application called png_permit_mng_features with a mask that
|
|
|
856 * included PNG_FLAG_MNG_FILTER_64 and
|
|
|
857 * 4. The filter_method is 64 and
|
|
|
858 * 5. The color_type is RGB or RGBA
|
|
|
859 */
|
|
|
860 if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
|
|
|
861 (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
|
|
|
862 {
|
|
|
863 /* Intrapixel differencing */
|
|
|
864 png_do_write_intrapixel(&row_info, png_ptr->row_buf + 1);
|
|
|
865 }
|
|
|
866 #endif
|
|
|
867
|
|
|
868 /* Added at libpng-1.5.10 */
|
|
|
869 #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
|
|
|
870 /* Check for out-of-range palette index */
|
|
|
871 if (row_info.color_type == PNG_COLOR_TYPE_PALETTE &&
|
|
|
872 png_ptr->num_palette_max >= 0)
|
|
|
873 png_do_check_palette_indexes(png_ptr, &row_info);
|
|
|
874 #endif
|
|
|
875
|
|
|
876 /* Find a filter if necessary, filter the row and write it out. */
|
|
|
877 png_write_find_filter(png_ptr, &row_info);
|
|
|
878
|
|
|
879 if (png_ptr->write_row_fn != NULL)
|
|
|
880 (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
|
|
|
881 }
|
|
|
882
|
|
|
883 #ifdef PNG_WRITE_FLUSH_SUPPORTED
|
|
|
884 /* Set the automatic flush interval or 0 to turn flushing off */
|
|
|
885 void PNGAPI
|
|
|
886 png_set_flush(png_structrp png_ptr, int nrows)
|
|
|
887 {
|
|
|
888 png_debug(1, "in png_set_flush");
|
|
|
889
|
|
|
890 if (png_ptr == NULL)
|
|
|
891 return;
|
|
|
892
|
|
|
893 png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
|
|
|
894 }
|
|
|
895
|
|
|
896 /* Flush the current output buffers now */
|
|
|
897 void PNGAPI
|
|
|
898 png_write_flush(png_structrp png_ptr)
|
|
|
899 {
|
|
|
900 png_debug(1, "in png_write_flush");
|
|
|
901
|
|
|
902 if (png_ptr == NULL)
|
|
|
903 return;
|
|
|
904
|
|
|
905 /* We have already written out all of the data */
|
|
|
906 if (png_ptr->row_number >= png_ptr->num_rows)
|
|
|
907 return;
|
|
|
908
|
|
|
909 png_compress_IDAT(png_ptr, NULL, 0, Z_SYNC_FLUSH);
|
|
|
910 png_ptr->flush_rows = 0;
|
|
|
911 png_flush(png_ptr);
|
|
|
912 }
|
|
|
913 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
|
|
|
914
|
|
|
915 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
|
|
|
916 static void png_reset_filter_heuristics(png_structrp png_ptr);/* forward decl */
|
|
|
917 #endif
|
|
|
918
|
|
|
919 /* Free any memory used in png_ptr struct without freeing the struct itself. */
|
|
|
920 static void
|
|
|
921 png_write_destroy(png_structrp png_ptr)
|
|
|
922 {
|
|
|
923 png_debug(1, "in png_write_destroy");
|
|
|
924
|
|
|
925 /* Free any memory zlib uses */
|
|
|
926 if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
|
|
|
927 deflateEnd(&png_ptr->zstream);
|
|
|
928
|
|
|
929 /* Free our memory. png_free checks NULL for us. */
|
|
|
930 png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
|
|
|
931 png_free(png_ptr, png_ptr->row_buf);
|
|
|
932 #ifdef PNG_WRITE_FILTER_SUPPORTED
|
|
|
933 png_free(png_ptr, png_ptr->prev_row);
|
|
|
934 png_free(png_ptr, png_ptr->sub_row);
|
|
|
935 png_free(png_ptr, png_ptr->up_row);
|
|
|
936 png_free(png_ptr, png_ptr->avg_row);
|
|
|
937 png_free(png_ptr, png_ptr->paeth_row);
|
|
|
938 #endif
|
|
|
939
|
|
|
940 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
|
|
|
941 /* Use this to save a little code space, it doesn't free the filter_costs */
|
|
|
942 png_reset_filter_heuristics(png_ptr);
|
|
|
943 png_free(png_ptr, png_ptr->filter_costs);
|
|
|
944 png_free(png_ptr, png_ptr->inv_filter_costs);
|
|
|
945 #endif
|
|
|
946
|
|
|
947 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
|
|
|
948 png_free(png_ptr, png_ptr->chunk_list);
|
|
|
949 #endif
|
|
|
950
|
|
|
951 /* The error handling and memory handling information is left intact at this
|
|
|
952 * point: the jmp_buf may still have to be freed. See png_destroy_png_struct
|
|
|
953 * for how this happens.
|
|
|
954 */
|
|
|
955 }
|
|
|
956
|
|
|
957 /* Free all memory used by the write.
|
|
|
958 * In libpng 1.6.0 this API changed quietly to no longer accept a NULL value for
|
|
|
959 * *png_ptr_ptr. Prior to 1.6.0 it would accept such a value and it would free
|
|
|
960 * the passed in info_structs but it would quietly fail to free any of the data
|
|
|
961 * inside them. In 1.6.0 it quietly does nothing (it has to be quiet because it
|
|
|
962 * has no png_ptr.)
|
|
|
963 */
|
|
|
964 void PNGAPI
|
|
|
965 png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
|
|
|
966 {
|
|
|
967 png_debug(1, "in png_destroy_write_struct");
|
|
|
968
|
|
|
969 if (png_ptr_ptr != NULL)
|
|
|
970 {
|
|
|
971 png_structrp png_ptr = *png_ptr_ptr;
|
|
|
972
|
|
|
973 if (png_ptr != NULL) /* added in libpng 1.6.0 */
|
|
|
974 {
|
|
|
975 png_destroy_info_struct(png_ptr, info_ptr_ptr);
|
|
|
976
|
|
|
977 *png_ptr_ptr = NULL;
|
|
|
978 png_write_destroy(png_ptr);
|
|
|
979 png_destroy_png_struct(png_ptr);
|
|
|
980 }
|
|
|
981 }
|
|
|
982 }
|
|
|
983
|
|
|
984 /* Allow the application to select one or more row filters to use. */
|
|
|
985 void PNGAPI
|
|
|
986 png_set_filter(png_structrp png_ptr, int method, int filters)
|
|
|
987 {
|
|
|
988 png_debug(1, "in png_set_filter");
|
|
|
989
|
|
|
990 if (png_ptr == NULL)
|
|
|
991 return;
|
|
|
992
|
|
|
993 #ifdef PNG_MNG_FEATURES_SUPPORTED
|
|
|
994 if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
|
|
|
995 (method == PNG_INTRAPIXEL_DIFFERENCING))
|
|
|
996 method = PNG_FILTER_TYPE_BASE;
|
|
|
997
|
|
|
998 #endif
|
|
|
999 if (method == PNG_FILTER_TYPE_BASE)
|
|
|
1000 {
|
|
|
1001 switch (filters & (PNG_ALL_FILTERS | 0x07))
|
|
|
1002 {
|
|
|
1003 #ifdef PNG_WRITE_FILTER_SUPPORTED
|
|
|
1004 case 5:
|
|
|
1005 case 6:
|
|
|
1006 case 7: png_app_error(png_ptr, "Unknown row filter for method 0");
|
|
|
1007 /* FALL THROUGH */
|
|
|
1008 #endif /* PNG_WRITE_FILTER_SUPPORTED */
|
|
|
1009 case PNG_FILTER_VALUE_NONE:
|
|
|
1010 png_ptr->do_filter = PNG_FILTER_NONE; break;
|
|
|
1011
|
|
|
1012 #ifdef PNG_WRITE_FILTER_SUPPORTED
|
|
|
1013 case PNG_FILTER_VALUE_SUB:
|
|
|
1014 png_ptr->do_filter = PNG_FILTER_SUB; break;
|
|
|
1015
|
|
|
1016 case PNG_FILTER_VALUE_UP:
|
|
|
1017 png_ptr->do_filter = PNG_FILTER_UP; break;
|
|
|
1018
|
|
|
1019 case PNG_FILTER_VALUE_AVG:
|
|
|
1020 png_ptr->do_filter = PNG_FILTER_AVG; break;
|
|
|
1021
|
|
|
1022 case PNG_FILTER_VALUE_PAETH:
|
|
|
1023 png_ptr->do_filter = PNG_FILTER_PAETH; break;
|
|
|
1024
|
|
|
1025 default:
|
|
|
1026 png_ptr->do_filter = (png_byte)filters; break;
|
|
|
1027 #else
|
|
|
1028 default:
|
|
|
1029 png_app_error(png_ptr, "Unknown row filter for method 0");
|
|
|
1030 #endif /* PNG_WRITE_FILTER_SUPPORTED */
|
|
|
1031 }
|
|
|
1032
|
|
|
1033 /* If we have allocated the row_buf, this means we have already started
|
|
|
1034 * with the image and we should have allocated all of the filter buffers
|
|
|
1035 * that have been selected. If prev_row isn't already allocated, then
|
|
|
1036 * it is too late to start using the filters that need it, since we
|
|
|
1037 * will be missing the data in the previous row. If an application
|
|
|
1038 * wants to start and stop using particular filters during compression,
|
|
|
1039 * it should start out with all of the filters, and then add and
|
|
|
1040 * remove them after the start of compression.
|
|
|
1041 */
|
|
|
1042 if (png_ptr->row_buf != NULL)
|
|
|
1043 {
|
|
|
1044 #ifdef PNG_WRITE_FILTER_SUPPORTED
|
|
|
1045 if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
|
|
|
1046 {
|
|
|
1047 png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
|
|
|
1048 (png_ptr->rowbytes + 1));
|
|
|
1049 png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
|
|
|
1050 }
|
|
|
1051
|
|
|
1052 if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
|
|
|
1053 {
|
|
|
1054 if (png_ptr->prev_row == NULL)
|
|
|
1055 {
|
|
|
1056 png_warning(png_ptr, "Can't add Up filter after starting");
|
|
|
1057 png_ptr->do_filter = (png_byte)(png_ptr->do_filter &
|
|
|
1058 ~PNG_FILTER_UP);
|
|
|
1059 }
|
|
|
1060
|
|
|
1061 else
|
|
|
1062 {
|
|
|
1063 png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
|
|
|
1064 (png_ptr->rowbytes + 1));
|
|
|
1065 png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
|
|
|
1066 }
|
|
|
1067 }
|
|
|
1068
|
|
|
1069 if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
|
|
|
1070 {
|
|
|
1071 if (png_ptr->prev_row == NULL)
|
|
|
1072 {
|
|
|
1073 png_warning(png_ptr, "Can't add Average filter after starting");
|
|
|
1074 png_ptr->do_filter = (png_byte)(png_ptr->do_filter &
|
|
|
1075 ~PNG_FILTER_AVG);
|
|
|
1076 }
|
|
|
1077
|
|
|
1078 else
|
|
|
1079 {
|
|
|
1080 png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
|
|
|
1081 (png_ptr->rowbytes + 1));
|
|
|
1082 png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
|
|
|
1083 }
|
|
|
1084 }
|
|
|
1085
|
|
|
1086 if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
|
|
|
1087 png_ptr->paeth_row == NULL)
|
|
|
1088 {
|
|
|
1089 if (png_ptr->prev_row == NULL)
|
|
|
1090 {
|
|
|
1091 png_warning(png_ptr, "Can't add Paeth filter after starting");
|
|
|
1092 png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
|
|
|
1093 }
|
|
|
1094
|
|
|
1095 else
|
|
|
1096 {
|
|
|
1097 png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
|
|
|
1098 (png_ptr->rowbytes + 1));
|
|
|
1099 png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
|
|
|
1100 }
|
|
|
1101 }
|
|
|
1102
|
|
|
1103 if (png_ptr->do_filter == PNG_NO_FILTERS)
|
|
|
1104 #endif /* PNG_WRITE_FILTER_SUPPORTED */
|
|
|
1105 png_ptr->do_filter = PNG_FILTER_NONE;
|
|
|
1106 }
|
|
|
1107 }
|
|
|
1108 else
|
|
|
1109 png_error(png_ptr, "Unknown custom filter method");
|
|
|
1110 }
|
|
|
1111
|
|
|
1112 /* This allows us to influence the way in which libpng chooses the "best"
|
|
|
1113 * filter for the current scanline. While the "minimum-sum-of-absolute-
|
|
|
1114 * differences metric is relatively fast and effective, there is some
|
|
|
1115 * question as to whether it can be improved upon by trying to keep the
|
|
|
1116 * filtered data going to zlib more consistent, hopefully resulting in
|
|
|
1117 * better compression.
|
|
|
1118 */
|
|
|
1119 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* GRR 970116 */
|
|
|
1120 /* Convenience reset API. */
|
|
|
1121 static void
|
|
|
1122 png_reset_filter_heuristics(png_structrp png_ptr)
|
|
|
1123 {
|
|
|
1124 /* Clear out any old values in the 'weights' - this must be done because if
|
|
|
1125 * the app calls set_filter_heuristics multiple times with different
|
|
|
1126 * 'num_weights' values we would otherwise potentially have wrong sized
|
|
|
1127 * arrays.
|
|
|
1128 */
|
|
|
1129 png_ptr->num_prev_filters = 0;
|
|
|
1130 png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
|
|
|
1131 if (png_ptr->prev_filters != NULL)
|
|
|
1132 {
|
|
|
1133 png_bytep old = png_ptr->prev_filters;
|
|
|
1134 png_ptr->prev_filters = NULL;
|
|
|
1135 png_free(png_ptr, old);
|
|
|
1136 }
|
|
|
1137 if (png_ptr->filter_weights != NULL)
|
|
|
1138 {
|
|
|
1139 png_uint_16p old = png_ptr->filter_weights;
|
|
|
1140 png_ptr->filter_weights = NULL;
|
|
|
1141 png_free(png_ptr, old);
|
|
|
1142 }
|
|
|
1143
|
|
|
1144 if (png_ptr->inv_filter_weights != NULL)
|
|
|
1145 {
|
|
|
1146 png_uint_16p old = png_ptr->inv_filter_weights;
|
|
|
1147 png_ptr->inv_filter_weights = NULL;
|
|
|
1148 png_free(png_ptr, old);
|
|
|
1149 }
|
|
|
1150
|
|
|
1151 /* Leave the filter_costs - this array is fixed size. */
|
|
|
1152 }
|
|
|
1153
|
|
|
1154 static int
|
|
|
1155 png_init_filter_heuristics(png_structrp png_ptr, int heuristic_method,
|
|
|
1156 int num_weights)
|
|
|
1157 {
|
|
|
1158 if (png_ptr == NULL)
|
|
|
1159 return 0;
|
|
|
1160
|
|
|
1161 /* Clear out the arrays */
|
|
|
1162 png_reset_filter_heuristics(png_ptr);
|
|
|
1163
|
|
|
1164 /* Check arguments; the 'reset' function makes the correct settings for the
|
|
|
1165 * unweighted case, but we must handle the weight case by initializing the
|
|
|
1166 * arrays for the caller.
|
|
|
1167 */
|
|
|
1168 if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
1169 {
|
|
|
1170 int i;
|
|
|
1171
|
|
|
1172 if (num_weights > 0)
|
|
|
1173 {
|
|
|
1174 png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
|
|
|
1175 (png_uint_32)((sizeof (png_byte)) * num_weights));
|
|
|
1176
|
|
|
1177 /* To make sure that the weighting starts out fairly */
|
|
|
1178 for (i = 0; i < num_weights; i++)
|
|
|
1179 {
|
|
|
1180 png_ptr->prev_filters[i] = 255;
|
|
|
1181 }
|
|
|
1182
|
|
|
1183 png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
|
|
|
1184 (png_uint_32)((sizeof (png_uint_16)) * num_weights));
|
|
|
1185
|
|
|
1186 png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
|
|
|
1187 (png_uint_32)((sizeof (png_uint_16)) * num_weights));
|
|
|
1188
|
|
|
1189 for (i = 0; i < num_weights; i++)
|
|
|
1190 {
|
|
|
1191 png_ptr->inv_filter_weights[i] =
|
|
|
1192 png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
|
|
|
1193 }
|
|
|
1194
|
|
|
1195 /* Safe to set this now */
|
|
|
1196 png_ptr->num_prev_filters = (png_byte)num_weights;
|
|
|
1197 }
|
|
|
1198
|
|
|
1199 /* If, in the future, there are other filter methods, this would
|
|
|
1200 * need to be based on png_ptr->filter.
|
|
|
1201 */
|
|
|
1202 if (png_ptr->filter_costs == NULL)
|
|
|
1203 {
|
|
|
1204 png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
|
|
|
1205 (png_uint_32)((sizeof (png_uint_16)) * PNG_FILTER_VALUE_LAST));
|
|
|
1206
|
|
|
1207 png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
|
|
|
1208 (png_uint_32)((sizeof (png_uint_16)) * PNG_FILTER_VALUE_LAST));
|
|
|
1209 }
|
|
|
1210
|
|
|
1211 for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
|
|
|
1212 {
|
|
|
1213 png_ptr->inv_filter_costs[i] =
|
|
|
1214 png_ptr->filter_costs[i] = PNG_COST_FACTOR;
|
|
|
1215 }
|
|
|
1216
|
|
|
1217 /* All the arrays are inited, safe to set this: */
|
|
|
1218 png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_WEIGHTED;
|
|
|
1219
|
|
|
1220 /* Return the 'ok' code. */
|
|
|
1221 return 1;
|
|
|
1222 }
|
|
|
1223 else if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT ||
|
|
|
1224 heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
|
|
|
1225 {
|
|
|
1226 return 1;
|
|
|
1227 }
|
|
|
1228 else
|
|
|
1229 {
|
|
|
1230 png_warning(png_ptr, "Unknown filter heuristic method");
|
|
|
1231 return 0;
|
|
|
1232 }
|
|
|
1233 }
|
|
|
1234
|
|
|
1235 /* Provide floating and fixed point APIs */
|
|
|
1236 #ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
|
1237 void PNGAPI
|
|
|
1238 png_set_filter_heuristics(png_structrp png_ptr, int heuristic_method,
|
|
|
1239 int num_weights, png_const_doublep filter_weights,
|
|
|
1240 png_const_doublep filter_costs)
|
|
|
1241 {
|
|
|
1242 png_debug(1, "in png_set_filter_heuristics");
|
|
|
1243
|
|
|
1244 /* The internal API allocates all the arrays and ensures that the elements of
|
|
|
1245 * those arrays are set to the default value.
|
|
|
1246 */
|
|
|
1247 if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
|
|
|
1248 return;
|
|
|
1249
|
|
|
1250 /* If using the weighted method copy in the weights. */
|
|
|
1251 if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
1252 {
|
|
|
1253 int i;
|
|
|
1254 for (i = 0; i < num_weights; i++)
|
|
|
1255 {
|
|
|
1256 if (filter_weights[i] <= 0.0)
|
|
|
1257 {
|
|
|
1258 png_ptr->inv_filter_weights[i] =
|
|
|
1259 png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
|
|
|
1260 }
|
|
|
1261
|
|
|
1262 else
|
|
|
1263 {
|
|
|
1264 png_ptr->inv_filter_weights[i] =
|
|
|
1265 (png_uint_16)(PNG_WEIGHT_FACTOR*filter_weights[i]+.5);
|
|
|
1266
|
|
|
1267 png_ptr->filter_weights[i] =
|
|
|
1268 (png_uint_16)(PNG_WEIGHT_FACTOR/filter_weights[i]+.5);
|
|
|
1269 }
|
|
|
1270 }
|
|
|
1271
|
|
|
1272 /* Here is where we set the relative costs of the different filters. We
|
|
|
1273 * should take the desired compression level into account when setting
|
|
|
1274 * the costs, so that Paeth, for instance, has a high relative cost at low
|
|
|
1275 * compression levels, while it has a lower relative cost at higher
|
|
|
1276 * compression settings. The filter types are in order of increasing
|
|
|
1277 * relative cost, so it would be possible to do this with an algorithm.
|
|
|
1278 */
|
|
|
1279 for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) if (filter_costs[i] >= 1.0)
|
|
|
1280 {
|
|
|
1281 png_ptr->inv_filter_costs[i] =
|
|
|
1282 (png_uint_16)(PNG_COST_FACTOR / filter_costs[i] + .5);
|
|
|
1283
|
|
|
1284 png_ptr->filter_costs[i] =
|
|
|
1285 (png_uint_16)(PNG_COST_FACTOR * filter_costs[i] + .5);
|
|
|
1286 }
|
|
|
1287 }
|
|
|
1288 }
|
|
|
1289 #endif /* FLOATING_POINT */
|
|
|
1290
|
|
|
1291 #ifdef PNG_FIXED_POINT_SUPPORTED
|
|
|
1292 void PNGAPI
|
|
|
1293 png_set_filter_heuristics_fixed(png_structrp png_ptr, int heuristic_method,
|
|
|
1294 int num_weights, png_const_fixed_point_p filter_weights,
|
|
|
1295 png_const_fixed_point_p filter_costs)
|
|
|
1296 {
|
|
|
1297 png_debug(1, "in png_set_filter_heuristics_fixed");
|
|
|
1298
|
|
|
1299 /* The internal API allocates all the arrays and ensures that the elements of
|
|
|
1300 * those arrays are set to the default value.
|
|
|
1301 */
|
|
|
1302 if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
|
|
|
1303 return;
|
|
|
1304
|
|
|
1305 /* If using the weighted method copy in the weights. */
|
|
|
1306 if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
|
1307 {
|
|
|
1308 int i;
|
|
|
1309 for (i = 0; i < num_weights; i++)
|
|
|
1310 {
|
|
|
1311 if (filter_weights[i] <= 0)
|
|
|
1312 {
|
|
|
1313 png_ptr->inv_filter_weights[i] =
|
|
|
1314 png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
|
|
|
1315 }
|
|
|
1316
|
|
|
1317 else
|
|
|
1318 {
|
|
|
1319 png_ptr->inv_filter_weights[i] = (png_uint_16)
|
|
|
1320 ((PNG_WEIGHT_FACTOR*filter_weights[i]+PNG_FP_HALF)/PNG_FP_1);
|
|
|
1321
|
|
|
1322 png_ptr->filter_weights[i] = (png_uint_16)((PNG_WEIGHT_FACTOR*
|
|
|
1323 PNG_FP_1+(filter_weights[i]/2))/filter_weights[i]);
|
|
|
1324 }
|
|
|
1325 }
|
|
|
1326
|
|
|
1327 /* Here is where we set the relative costs of the different filters. We
|
|
|
1328 * should take the desired compression level into account when setting
|
|
|
1329 * the costs, so that Paeth, for instance, has a high relative cost at low
|
|
|
1330 * compression levels, while it has a lower relative cost at higher
|
|
|
1331 * compression settings. The filter types are in order of increasing
|
|
|
1332 * relative cost, so it would be possible to do this with an algorithm.
|
|
|
1333 */
|
|
|
1334 for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
|
|
|
1335 if (filter_costs[i] >= PNG_FP_1)
|
|
|
1336 {
|
|
|
1337 png_uint_32 tmp;
|
|
|
1338
|
|
|
1339 /* Use a 32 bit unsigned temporary here because otherwise the
|
|
|
1340 * intermediate value will be a 32 bit *signed* integer (ANSI rules)
|
|
|
1341 * and this will get the wrong answer on division.
|
|
|
1342 */
|
|
|
1343 tmp = PNG_COST_FACTOR*PNG_FP_1 + (filter_costs[i]/2);
|
|
|
1344 tmp /= filter_costs[i];
|
|
|
1345
|
|
|
1346 png_ptr->inv_filter_costs[i] = (png_uint_16)tmp;
|
|
|
1347
|
|
|
1348 tmp = PNG_COST_FACTOR * filter_costs[i] + PNG_FP_HALF;
|
|
|
1349 tmp /= PNG_FP_1;
|
|
|
1350
|
|
|
1351 png_ptr->filter_costs[i] = (png_uint_16)tmp;
|
|
|
1352 }
|
|
|
1353 }
|
|
|
1354 }
|
|
|
1355 #endif /* FIXED_POINT */
|
|
|
1356 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
|
|
|
1357
|
|
|
1358 void PNGAPI
|
|
|
1359 png_set_compression_level(png_structrp png_ptr, int level)
|
|
|
1360 {
|
|
|
1361 png_debug(1, "in png_set_compression_level");
|
|
|
1362
|
|
|
1363 if (png_ptr == NULL)
|
|
|
1364 return;
|
|
|
1365
|
|
|
1366 png_ptr->zlib_level = level;
|
|
|
1367 }
|
|
|
1368
|
|
|
1369 void PNGAPI
|
|
|
1370 png_set_compression_mem_level(png_structrp png_ptr, int mem_level)
|
|
|
1371 {
|
|
|
1372 png_debug(1, "in png_set_compression_mem_level");
|
|
|
1373
|
|
|
1374 if (png_ptr == NULL)
|
|
|
1375 return;
|
|
|
1376
|
|
|
1377 png_ptr->zlib_mem_level = mem_level;
|
|
|
1378 }
|
|
|
1379
|
|
|
1380 void PNGAPI
|
|
|
1381 png_set_compression_strategy(png_structrp png_ptr, int strategy)
|
|
|
1382 {
|
|
|
1383 png_debug(1, "in png_set_compression_strategy");
|
|
|
1384
|
|
|
1385 if (png_ptr == NULL)
|
|
|
1386 return;
|
|
|
1387
|
|
|
1388 /* The flag setting here prevents the libpng dynamic selection of strategy.
|
|
|
1389 */
|
|
|
1390 png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
|
|
|
1391 png_ptr->zlib_strategy = strategy;
|
|
|
1392 }
|
|
|
1393
|
|
|
1394 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
|
|
|
1395 * smaller value of window_bits if it can do so safely.
|
|
|
1396 */
|
|
|
1397 void PNGAPI
|
|
|
1398 png_set_compression_window_bits(png_structrp png_ptr, int window_bits)
|
|
|
1399 {
|
|
|
1400 if (png_ptr == NULL)
|
|
|
1401 return;
|
|
|
1402
|
|
|
1403 /* Prior to 1.6.0 this would warn but then set the window_bits value, this
|
|
|
1404 * meant that negative window bits values could be selected which would cause
|
|
|
1405 * libpng to write a non-standard PNG file with raw deflate or gzip
|
|
|
1406 * compressed IDAT or ancillary chunks. Such files can be read and there is
|
|
|
1407 * no warning on read, so this seems like a very bad idea.
|
|
|
1408 */
|
|
|
1409 if (window_bits > 15)
|
|
|
1410 {
|
|
|
1411 png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
|
|
|
1412 window_bits = 15;
|
|
|
1413 }
|
|
|
1414
|
|
|
1415 else if (window_bits < 8)
|
|
|
1416 {
|
|
|
1417 png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
|
|
|
1418 window_bits = 8;
|
|
|
1419 }
|
|
|
1420
|
|
|
1421 png_ptr->zlib_window_bits = window_bits;
|
|
|
1422 }
|
|
|
1423
|
|
|
1424 void PNGAPI
|
|
|
1425 png_set_compression_method(png_structrp png_ptr, int method)
|
|
|
1426 {
|
|
|
1427 png_debug(1, "in png_set_compression_method");
|
|
|
1428
|
|
|
1429 if (png_ptr == NULL)
|
|
|
1430 return;
|
|
|
1431
|
|
|
1432 /* This would produce an invalid PNG file if it worked, but it doesn't and
|
|
|
1433 * deflate will fault it, so it is harmless to just warn here.
|
|
|
1434 */
|
|
|
1435 if (method != 8)
|
|
|
1436 png_warning(png_ptr, "Only compression method 8 is supported by PNG");
|
|
|
1437
|
|
|
1438 png_ptr->zlib_method = method;
|
|
|
1439 }
|
|
|
1440
|
|
|
1441 /* The following were added to libpng-1.5.4 */
|
|
|
1442 #ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
|
|
|
1443 void PNGAPI
|
|
|
1444 png_set_text_compression_level(png_structrp png_ptr, int level)
|
|
|
1445 {
|
|
|
1446 png_debug(1, "in png_set_text_compression_level");
|
|
|
1447
|
|
|
1448 if (png_ptr == NULL)
|
|
|
1449 return;
|
|
|
1450
|
|
|
1451 png_ptr->zlib_text_level = level;
|
|
|
1452 }
|
|
|
1453
|
|
|
1454 void PNGAPI
|
|
|
1455 png_set_text_compression_mem_level(png_structrp png_ptr, int mem_level)
|
|
|
1456 {
|
|
|
1457 png_debug(1, "in png_set_text_compression_mem_level");
|
|
|
1458
|
|
|
1459 if (png_ptr == NULL)
|
|
|
1460 return;
|
|
|
1461
|
|
|
1462 png_ptr->zlib_text_mem_level = mem_level;
|
|
|
1463 }
|
|
|
1464
|
|
|
1465 void PNGAPI
|
|
|
1466 png_set_text_compression_strategy(png_structrp png_ptr, int strategy)
|
|
|
1467 {
|
|
|
1468 png_debug(1, "in png_set_text_compression_strategy");
|
|
|
1469
|
|
|
1470 if (png_ptr == NULL)
|
|
|
1471 return;
|
|
|
1472
|
|
|
1473 png_ptr->zlib_text_strategy = strategy;
|
|
|
1474 }
|
|
|
1475
|
|
|
1476 /* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
|
|
|
1477 * smaller value of window_bits if it can do so safely.
|
|
|
1478 */
|
|
|
1479 void PNGAPI
|
|
|
1480 png_set_text_compression_window_bits(png_structrp png_ptr, int window_bits)
|
|
|
1481 {
|
|
|
1482 if (png_ptr == NULL)
|
|
|
1483 return;
|
|
|
1484
|
|
|
1485 if (window_bits > 15)
|
|
|
1486 {
|
|
|
1487 png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
|
|
|
1488 window_bits = 15;
|
|
|
1489 }
|
|
|
1490
|
|
|
1491 else if (window_bits < 8)
|
|
|
1492 {
|
|
|
1493 png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
|
|
|
1494 window_bits = 8;
|
|
|
1495 }
|
|
|
1496
|
|
|
1497 png_ptr->zlib_text_window_bits = window_bits;
|
|
|
1498 }
|
|
|
1499
|
|
|
1500 void PNGAPI
|
|
|
1501 png_set_text_compression_method(png_structrp png_ptr, int method)
|
|
|
1502 {
|
|
|
1503 png_debug(1, "in png_set_text_compression_method");
|
|
|
1504
|
|
|
1505 if (png_ptr == NULL)
|
|
|
1506 return;
|
|
|
1507
|
|
|
1508 if (method != 8)
|
|
|
1509 png_warning(png_ptr, "Only compression method 8 is supported by PNG");
|
|
|
1510
|
|
|
1511 png_ptr->zlib_text_method = method;
|
|
|
1512 }
|
|
|
1513 #endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
|
|
|
1514 /* end of API added to libpng-1.5.4 */
|
|
|
1515
|
|
|
1516 void PNGAPI
|
|
|
1517 png_set_write_status_fn(png_structrp png_ptr, png_write_status_ptr write_row_fn)
|
|
|
1518 {
|
|
|
1519 if (png_ptr == NULL)
|
|
|
1520 return;
|
|
|
1521
|
|
|
1522 png_ptr->write_row_fn = write_row_fn;
|
|
|
1523 }
|
|
|
1524
|
|
|
1525 #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
|
|
|
1526 void PNGAPI
|
|
|
1527 png_set_write_user_transform_fn(png_structrp png_ptr, png_user_transform_ptr
|
|
|
1528 write_user_transform_fn)
|
|
|
1529 {
|
|
|
1530 png_debug(1, "in png_set_write_user_transform_fn");
|
|
|
1531
|
|
|
1532 if (png_ptr == NULL)
|
|
|
1533 return;
|
|
|
1534
|
|
|
1535 png_ptr->transformations |= PNG_USER_TRANSFORM;
|
|
|
1536 png_ptr->write_user_transform_fn = write_user_transform_fn;
|
|
|
1537 }
|
|
|
1538 #endif
|
|
|
1539
|
|
|
1540
|
|
|
1541 #ifdef PNG_INFO_IMAGE_SUPPORTED
|
|
|
1542 void PNGAPI
|
|
|
1543 png_write_png(png_structrp png_ptr, png_inforp info_ptr,
|
|
|
1544 int transforms, voidp params)
|
|
|
1545 {
|
|
|
1546 if (png_ptr == NULL || info_ptr == NULL)
|
|
|
1547 return;
|
|
|
1548
|
|
|
1549 if ((info_ptr->valid & PNG_INFO_IDAT) == 0)
|
|
|
1550 {
|
|
|
1551 png_app_error(png_ptr, "no rows for png_write_image to write");
|
|
|
1552 return;
|
|
|
1553 }
|
|
|
1554
|
|
|
1555 /* Write the file header information. */
|
|
|
1556 png_write_info(png_ptr, info_ptr);
|
|
|
1557
|
|
|
1558 /* ------ these transformations don't touch the info structure ------- */
|
|
|
1559
|
|
|
1560 /* Invert monochrome pixels */
|
|
|
1561 if (transforms & PNG_TRANSFORM_INVERT_MONO)
|
|
|
1562 #ifdef PNG_WRITE_INVERT_SUPPORTED
|
|
|
1563 png_set_invert_mono(png_ptr);
|
|
|
1564 #else
|
|
|
1565 png_app_error(png_ptr, "PNG_TRANSFORM_INVERT_MONO not supported");
|
|
|
1566 #endif
|
|
|
1567
|
|
|
1568 /* Shift the pixels up to a legal bit depth and fill in
|
|
|
1569 * as appropriate to correctly scale the image.
|
|
|
1570 */
|
|
|
1571 if (transforms & PNG_TRANSFORM_SHIFT)
|
|
|
1572 #ifdef PNG_WRITE_SHIFT_SUPPORTED
|
|
|
1573 if (info_ptr->valid & PNG_INFO_sBIT)
|
|
|
1574 png_set_shift(png_ptr, &info_ptr->sig_bit);
|
|
|
1575 #else
|
|
|
1576 png_app_error(png_ptr, "PNG_TRANSFORM_SHIFT not supported");
|
|
|
1577 #endif
|
|
|
1578
|
|
|
1579 /* Pack pixels into bytes */
|
|
|
1580 if (transforms & PNG_TRANSFORM_PACKING)
|
|
|
1581 #ifdef PNG_WRITE_PACK_SUPPORTED
|
|
|
1582 png_set_packing(png_ptr);
|
|
|
1583 #else
|
|
|
1584 png_app_error(png_ptr, "PNG_TRANSFORM_PACKING not supported");
|
|
|
1585 #endif
|
|
|
1586
|
|
|
1587 /* Swap location of alpha bytes from ARGB to RGBA */
|
|
|
1588 if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
|
|
|
1589 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
|
|
|
1590 png_set_swap_alpha(png_ptr);
|
|
|
1591 #else
|
|
|
1592 png_app_error(png_ptr, "PNG_TRANSFORM_SWAP_ALPHA not supported");
|
|
|
1593 #endif
|
|
|
1594
|
|
|
1595 /* Remove a filler (X) from XRGB/RGBX/AG/GA into to convert it into
|
|
|
1596 * RGB, note that the code expects the input color type to be G or RGB; no
|
|
|
1597 * alpha channel.
|
|
|
1598 */
|
|
|
1599 if (transforms &
|
|
|
1600 (PNG_TRANSFORM_STRIP_FILLER_AFTER|PNG_TRANSFORM_STRIP_FILLER_BEFORE))
|
|
|
1601 {
|
|
|
1602 #ifdef PNG_WRITE_FILLER_SUPPORTED
|
|
|
1603 if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER)
|
|
|
1604 {
|
|
|
1605 if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)
|
|
|
1606 png_app_error(png_ptr,
|
|
|
1607 "PNG_TRANSFORM_STRIP_FILLER: BEFORE+AFTER not supported");
|
|
|
1608
|
|
|
1609 /* Continue if ignored - this is the pre-1.6.10 behavior */
|
|
|
1610 png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
|
|
|
1611 }
|
|
|
1612
|
|
|
1613 else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)
|
|
|
1614 png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
|
|
|
1615 #else
|
|
|
1616 png_app_error(png_ptr, "PNG_TRANSFORM_STRIP_FILLER not supported");
|
|
|
1617 #endif
|
|
|
1618 }
|
|
|
1619
|
|
|
1620 /* Flip BGR pixels to RGB */
|
|
|
1621 if (transforms & PNG_TRANSFORM_BGR)
|
|
|
1622 #ifdef PNG_WRITE_BGR_SUPPORTED
|
|
|
1623 png_set_bgr(png_ptr);
|
|
|
1624 #else
|
|
|
1625 png_app_error(png_ptr, "PNG_TRANSFORM_BGR not supported");
|
|
|
1626 #endif
|
|
|
1627
|
|
|
1628 /* Swap bytes of 16-bit files to most significant byte first */
|
|
|
1629 if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
|
|
|
1630 #ifdef PNG_WRITE_SWAP_SUPPORTED
|
|
|
1631 png_set_swap(png_ptr);
|
|
|
1632 #else
|
|
|
1633 png_app_error(png_ptr, "PNG_TRANSFORM_SWAP_ENDIAN not supported");
|
|
|
1634 #endif
|
|
|
1635
|
|
|
1636 /* Swap bits of 1, 2, 4 bit packed pixel formats */
|
|
|
1637 if (transforms & PNG_TRANSFORM_PACKSWAP)
|
|
|
1638 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED
|
|
|
1639 png_set_packswap(png_ptr);
|
|
|
1640 #else
|
|
|
1641 png_app_error(png_ptr, "PNG_TRANSFORM_PACKSWAP not supported");
|
|
|
1642 #endif
|
|
|
1643
|
|
|
1644 /* Invert the alpha channel from opacity to transparency */
|
|
|
1645 if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
|
|
|
1646 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
|
|
|
1647 png_set_invert_alpha(png_ptr);
|
|
|
1648 #else
|
|
|
1649 png_app_error(png_ptr, "PNG_TRANSFORM_INVERT_ALPHA not supported");
|
|
|
1650 #endif
|
|
|
1651
|
|
|
1652 /* ----------------------- end of transformations ------------------- */
|
|
|
1653
|
|
|
1654 /* Write the bits */
|
|
|
1655 png_write_image(png_ptr, info_ptr->row_pointers);
|
|
|
1656
|
|
|
1657 /* It is REQUIRED to call this to finish writing the rest of the file */
|
|
|
1658 png_write_end(png_ptr, info_ptr);
|
|
|
1659
|
|
|
1660 PNG_UNUSED(params)
|
|
|
1661 }
|
|
|
1662 #endif
|
|
|
1663
|
|
|
1664
|
|
|
1665 #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
|
|
|
1666 #ifdef PNG_STDIO_SUPPORTED /* currently required for png_image_write_* */
|
|
|
1667 /* Initialize the write structure - general purpose utility. */
|
|
|
1668 static int
|
|
|
1669 png_image_write_init(png_imagep image)
|
|
|
1670 {
|
|
|
1671 png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, image,
|
|
|
1672 png_safe_error, png_safe_warning);
|
|
|
1673
|
|
|
1674 if (png_ptr != NULL)
|
|
|
1675 {
|
|
|
1676 png_infop info_ptr = png_create_info_struct(png_ptr);
|
|
|
1677
|
|
|
1678 if (info_ptr != NULL)
|
|
|
1679 {
|
|
|
1680 png_controlp control = png_voidcast(png_controlp,
|
|
|
1681 png_malloc_warn(png_ptr, (sizeof *control)));
|
|
|
1682
|
|
|
1683 if (control != NULL)
|
|
|
1684 {
|
|
|
1685 memset(control, 0, (sizeof *control));
|
|
|
1686
|
|
|
1687 control->png_ptr = png_ptr;
|
|
|
1688 control->info_ptr = info_ptr;
|
|
|
1689 control->for_write = 1;
|
|
|
1690
|
|
|
1691 image->opaque = control;
|
|
|
1692 return 1;
|
|
|
1693 }
|
|
|
1694
|
|
|
1695 /* Error clean up */
|
|
|
1696 png_destroy_info_struct(png_ptr, &info_ptr);
|
|
|
1697 }
|
|
|
1698
|
|
|
1699 png_destroy_write_struct(&png_ptr, NULL);
|
|
|
1700 }
|
|
|
1701
|
|
|
1702 return png_image_error(image, "png_image_write_: out of memory");
|
|
|
1703 }
|
|
|
1704
|
|
|
1705 /* Arguments to png_image_write_main: */
|
|
|
1706 typedef struct
|
|
|
1707 {
|
|
|
1708 /* Arguments: */
|
|
|
1709 png_imagep image;
|
|
|
1710 png_const_voidp buffer;
|
|
|
1711 png_int_32 row_stride;
|
|
|
1712 png_const_voidp colormap;
|
|
|
1713 int convert_to_8bit;
|
|
|
1714 /* Local variables: */
|
|
|
1715 png_const_voidp first_row;
|
|
|
1716 ptrdiff_t row_bytes;
|
|
|
1717 png_voidp local_row;
|
|
|
1718 } png_image_write_control;
|
|
|
1719
|
|
|
1720 /* Write png_uint_16 input to a 16-bit PNG; the png_ptr has already been set to
|
|
|
1721 * do any necessary byte swapping. The component order is defined by the
|
|
|
1722 * png_image format value.
|
|
|
1723 */
|
|
|
1724 static int
|
|
|
1725 png_write_image_16bit(png_voidp argument)
|
|
|
1726 {
|
|
|
1727 png_image_write_control *display = png_voidcast(png_image_write_control*,
|
|
|
1728 argument);
|
|
|
1729 png_imagep image = display->image;
|
|
|
1730 png_structrp png_ptr = image->opaque->png_ptr;
|
|
|
1731
|
|
|
1732 png_const_uint_16p input_row = png_voidcast(png_const_uint_16p,
|
|
|
1733 display->first_row);
|
|
|
1734 png_uint_16p output_row = png_voidcast(png_uint_16p, display->local_row);
|
|
|
1735 png_uint_16p row_end;
|
|
|
1736 const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
|
|
|
1737 int aindex = 0;
|
|
|
1738 png_uint_32 y = image->height;
|
|
|
1739
|
|
|
1740 if (image->format & PNG_FORMAT_FLAG_ALPHA)
|
|
|
1741 {
|
|
|
1742 # ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
|
|
|
1743 if (image->format & PNG_FORMAT_FLAG_AFIRST)
|
|
|
1744 {
|
|
|
1745 aindex = -1;
|
|
|
1746 ++input_row; /* To point to the first component */
|
|
|
1747 ++output_row;
|
|
|
1748 }
|
|
|
1749
|
|
|
1750 else
|
|
|
1751 # endif
|
|
|
1752 aindex = channels;
|
|
|
1753 }
|
|
|
1754
|
|
|
1755 else
|
|
|
1756 png_error(png_ptr, "png_write_image: internal call error");
|
|
|
1757
|
|
|
1758 /* Work out the output row end and count over this, note that the increment
|
|
|
1759 * above to 'row' means that row_end can actually be beyond the end of the
|
|
|
1760 * row; this is correct.
|
|
|
1761 */
|
|
|
1762 row_end = output_row + image->width * (channels+1);
|
|
|
1763
|
|
|
1764 while (y-- > 0)
|
|
|
1765 {
|
|
|
1766 png_const_uint_16p in_ptr = input_row;
|
|
|
1767 png_uint_16p out_ptr = output_row;
|
|
|
1768
|
|
|
1769 while (out_ptr < row_end)
|
|
|
1770 {
|
|
|
1771 const png_uint_16 alpha = in_ptr[aindex];
|
|
|
1772 png_uint_32 reciprocal = 0;
|
|
|
1773 int c;
|
|
|
1774
|
|
|
1775 out_ptr[aindex] = alpha;
|
|
|
1776
|
|
|
1777 /* Calculate a reciprocal. The correct calculation is simply
|
|
|
1778 * component/alpha*65535 << 15. (I.e. 15 bits of precision); this
|
|
|
1779 * allows correct rounding by adding .5 before the shift. 'reciprocal'
|
|
|
1780 * is only initialized when required.
|
|
|
1781 */
|
|
|
1782 if (alpha > 0 && alpha < 65535)
|
|
|
1783 reciprocal = ((0xffff<<15)+(alpha>>1))/alpha;
|
|
|
1784
|
|
|
1785 c = channels;
|
|
|
1786 do /* always at least one channel */
|
|
|
1787 {
|
|
|
1788 png_uint_16 component = *in_ptr++;
|
|
|
1789
|
|
|
1790 /* The following gives 65535 for an alpha of 0, which is fine,
|
|
|
1791 * otherwise if 0/0 is represented as some other value there is more
|
|
|
1792 * likely to be a discontinuity which will probably damage
|
|
|
1793 * compression when moving from a fully transparent area to a
|
|
|
1794 * nearly transparent one. (The assumption here is that opaque
|
|
|
1795 * areas tend not to be 0 intensity.)
|
|
|
1796 */
|
|
|
1797 if (component >= alpha)
|
|
|
1798 component = 65535;
|
|
|
1799
|
|
|
1800 /* component<alpha, so component/alpha is less than one and
|
|
|
1801 * component*reciprocal is less than 2^31.
|
|
|
1802 */
|
|
|
1803 else if (component > 0 && alpha < 65535)
|
|
|
1804 {
|
|
|
1805 png_uint_32 calc = component * reciprocal;
|
|
|
1806 calc += 16384; /* round to nearest */
|
|
|
1807 component = (png_uint_16)(calc >> 15);
|
|
|
1808 }
|
|
|
1809
|
|
|
1810 *out_ptr++ = component;
|
|
|
1811 }
|
|
|
1812 while (--c > 0);
|
|
|
1813
|
|
|
1814 /* Skip to next component (skip the intervening alpha channel) */
|
|
|
1815 ++in_ptr;
|
|
|
1816 ++out_ptr;
|
|
|
1817 }
|
|
|
1818
|
|
|
1819 png_write_row(png_ptr, png_voidcast(png_const_bytep, display->local_row));
|
|
|
1820 input_row += display->row_bytes/(sizeof (png_uint_16));
|
|
|
1821 }
|
|
|
1822
|
|
|
1823 return 1;
|
|
|
1824 }
|
|
|
1825
|
|
|
1826 /* Given 16-bit input (1 to 4 channels) write 8-bit output. If an alpha channel
|
|
|
1827 * is present it must be removed from the components, the components are then
|
|
|
1828 * written in sRGB encoding. No components are added or removed.
|
|
|
1829 *
|
|
|
1830 * Calculate an alpha reciprocal to reverse pre-multiplication. As above the
|
|
|
1831 * calculation can be done to 15 bits of accuracy; however, the output needs to
|
|
|
1832 * be scaled in the range 0..255*65535, so include that scaling here.
|
|
|
1833 */
|
|
|
1834 #define UNP_RECIPROCAL(alpha) ((((0xffff*0xff)<<7)+(alpha>>1))/alpha)
|
|
|
1835
|
|
|
1836 static png_byte
|
|
|
1837 png_unpremultiply(png_uint_32 component, png_uint_32 alpha,
|
|
|
1838 png_uint_32 reciprocal/*from the above macro*/)
|
|
|
1839 {
|
|
|
1840 /* The following gives 1.0 for an alpha of 0, which is fine, otherwise if 0/0
|
|
|
1841 * is represented as some other value there is more likely to be a
|
|
|
1842 * discontinuity which will probably damage compression when moving from a
|
|
|
1843 * fully transparent area to a nearly transparent one. (The assumption here
|
|
|
1844 * is that opaque areas tend not to be 0 intensity.)
|
|
|
1845 *
|
|
|
1846 * There is a rounding problem here; if alpha is less than 128 it will end up
|
|
|
1847 * as 0 when scaled to 8 bits. To avoid introducing spurious colors into the
|
|
|
1848 * output change for this too.
|
|
|
1849 */
|
|
|
1850 if (component >= alpha || alpha < 128)
|
|
|
1851 return 255;
|
|
|
1852
|
|
|
1853 /* component<alpha, so component/alpha is less than one and
|
|
|
1854 * component*reciprocal is less than 2^31.
|
|
|
1855 */
|
|
|
1856 else if (component > 0)
|
|
|
1857 {
|
|
|
1858 /* The test is that alpha/257 (rounded) is less than 255, the first value
|
|
|
1859 * that becomes 255 is 65407.
|
|
|
1860 * NOTE: this must agree with the PNG_DIV257 macro (which must, therefore,
|
|
|
1861 * be exact!) [Could also test reciprocal != 0]
|
|
|
1862 */
|
|
|
1863 if (alpha < 65407)
|
|
|
1864 {
|
|
|
1865 component *= reciprocal;
|
|
|
1866 component += 64; /* round to nearest */
|
|
|
1867 component >>= 7;
|
|
|
1868 }
|
|
|
1869
|
|
|
1870 else
|
|
|
1871 component *= 255;
|
|
|
1872
|
|
|
1873 /* Convert the component to sRGB. */
|
|
|
1874 return (png_byte)PNG_sRGB_FROM_LINEAR(component);
|
|
|
1875 }
|
|
|
1876
|
|
|
1877 else
|
|
|
1878 return 0;
|
|
|
1879 }
|
|
|
1880
|
|
|
1881 static int
|
|
|
1882 png_write_image_8bit(png_voidp argument)
|
|
|
1883 {
|
|
|
1884 png_image_write_control *display = png_voidcast(png_image_write_control*,
|
|
|
1885 argument);
|
|
|
1886 png_imagep image = display->image;
|
|
|
1887 png_structrp png_ptr = image->opaque->png_ptr;
|
|
|
1888
|
|
|
1889 png_const_uint_16p input_row = png_voidcast(png_const_uint_16p,
|
|
|
1890 display->first_row);
|
|
|
1891 png_bytep output_row = png_voidcast(png_bytep, display->local_row);
|
|
|
1892 png_uint_32 y = image->height;
|
|
|
1893 const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
|
|
|
1894
|
|
|
1895 if (image->format & PNG_FORMAT_FLAG_ALPHA)
|
|
|
1896 {
|
|
|
1897 png_bytep row_end;
|
|
|
1898 int aindex;
|
|
|
1899
|
|
|
1900 # ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
|
|
|
1901 if (image->format & PNG_FORMAT_FLAG_AFIRST)
|
|
|
1902 {
|
|
|
1903 aindex = -1;
|
|
|
1904 ++input_row; /* To point to the first component */
|
|
|
1905 ++output_row;
|
|
|
1906 }
|
|
|
1907
|
|
|
1908 else
|
|
|
1909 # endif
|
|
|
1910 aindex = channels;
|
|
|
1911
|
|
|
1912 /* Use row_end in place of a loop counter: */
|
|
|
1913 row_end = output_row + image->width * (channels+1);
|
|
|
1914
|
|
|
1915 while (y-- > 0)
|
|
|
1916 {
|
|
|
1917 png_const_uint_16p in_ptr = input_row;
|
|
|
1918 png_bytep out_ptr = output_row;
|
|
|
1919
|
|
|
1920 while (out_ptr < row_end)
|
|
|
1921 {
|
|
|
1922 png_uint_16 alpha = in_ptr[aindex];
|
|
|
1923 png_byte alphabyte = (png_byte)PNG_DIV257(alpha);
|
|
|
1924 png_uint_32 reciprocal = 0;
|
|
|
1925 int c;
|
|
|
1926
|
|
|
1927 /* Scale and write the alpha channel. */
|
|
|
1928 out_ptr[aindex] = alphabyte;
|
|
|
1929
|
|
|
1930 if (alphabyte > 0 && alphabyte < 255)
|
|
|
1931 reciprocal = UNP_RECIPROCAL(alpha);
|
|
|
1932
|
|
|
1933 c = channels;
|
|
|
1934 do /* always at least one channel */
|
|
|
1935 *out_ptr++ = png_unpremultiply(*in_ptr++, alpha, reciprocal);
|
|
|
1936 while (--c > 0);
|
|
|
1937
|
|
|
1938 /* Skip to next component (skip the intervening alpha channel) */
|
|
|
1939 ++in_ptr;
|
|
|
1940 ++out_ptr;
|
|
|
1941 } /* while out_ptr < row_end */
|
|
|
1942
|
|
|
1943 png_write_row(png_ptr, png_voidcast(png_const_bytep,
|
|
|
1944 display->local_row));
|
|
|
1945 input_row += display->row_bytes/(sizeof (png_uint_16));
|
|
|
1946 } /* while y */
|
|
|
1947 }
|
|
|
1948
|
|
|
1949 else
|
|
|
1950 {
|
|
|
1951 /* No alpha channel, so the row_end really is the end of the row and it
|
|
|
1952 * is sufficient to loop over the components one by one.
|
|
|
1953 */
|
|
|
1954 png_bytep row_end = output_row + image->width * channels;
|
|
|
1955
|
|
|
1956 while (y-- > 0)
|
|
|
1957 {
|
|
|
1958 png_const_uint_16p in_ptr = input_row;
|
|
|
1959 png_bytep out_ptr = output_row;
|
|
|
1960
|
|
|
1961 while (out_ptr < row_end)
|
|
|
1962 {
|
|
|
1963 png_uint_32 component = *in_ptr++;
|
|
|
1964
|
|
|
1965 component *= 255;
|
|
|
1966 *out_ptr++ = (png_byte)PNG_sRGB_FROM_LINEAR(component);
|
|
|
1967 }
|
|
|
1968
|
|
|
1969 png_write_row(png_ptr, output_row);
|
|
|
1970 input_row += display->row_bytes/(sizeof (png_uint_16));
|
|
|
1971 }
|
|
|
1972 }
|
|
|
1973
|
|
|
1974 return 1;
|
|
|
1975 }
|
|
|
1976
|
|
|
1977 static void
|
|
|
1978 png_image_set_PLTE(png_image_write_control *display)
|
|
|
1979 {
|
|
|
1980 const png_imagep image = display->image;
|
|
|
1981 const void *cmap = display->colormap;
|
|
|
1982 const int entries = image->colormap_entries > 256 ? 256 :
|
|
|
1983 (int)image->colormap_entries;
|
|
|
1984
|
|
|
1985 /* NOTE: the caller must check for cmap != NULL and entries != 0 */
|
|
|
1986 const png_uint_32 format = image->format;
|
|
|
1987 const int channels = PNG_IMAGE_SAMPLE_CHANNELS(format);
|
|
|
1988
|
|
|
1989 # if defined(PNG_FORMAT_BGR_SUPPORTED) &&\
|
|
|
1990 defined(PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED)
|
|
|
1991 const int afirst = (format & PNG_FORMAT_FLAG_AFIRST) != 0 &&
|
|
|
1992 (format & PNG_FORMAT_FLAG_ALPHA) != 0;
|
|
|
1993 # else
|
|
|
1994 # define afirst 0
|
|
|
1995 # endif
|
|
|
1996
|
|
|
1997 # ifdef PNG_FORMAT_BGR_SUPPORTED
|
|
|
1998 const int bgr = (format & PNG_FORMAT_FLAG_BGR) ? 2 : 0;
|
|
|
1999 # else
|
|
|
2000 # define bgr 0
|
|
|
2001 # endif
|
|
|
2002
|
|
|
2003 int i, num_trans;
|
|
|
2004 png_color palette[256];
|
|
|
2005 png_byte tRNS[256];
|
|
|
2006
|
|
|
2007 memset(tRNS, 255, (sizeof tRNS));
|
|
|
2008 memset(palette, 0, (sizeof palette));
|
|
|
2009
|
|
|
2010 for (i=num_trans=0; i<entries; ++i)
|
|
|
2011 {
|
|
|
2012 /* This gets automatically converted to sRGB with reversal of the
|
|
|
2013 * pre-multiplication if the color-map has an alpha channel.
|
|
|
2014 */
|
|
|
2015 if (format & PNG_FORMAT_FLAG_LINEAR)
|
|
|
2016 {
|
|
|
2017 png_const_uint_16p entry = png_voidcast(png_const_uint_16p, cmap);
|
|
|
2018
|
|
|
2019 entry += i * channels;
|
|
|
2020
|
|
|
2021 if (channels & 1) /* no alpha */
|
|
|
2022 {
|
|
|
2023 if (channels >= 3) /* RGB */
|
|
|
2024 {
|
|
|
2025 palette[i].blue = (png_byte)PNG_sRGB_FROM_LINEAR(255 *
|
|
|
2026 entry[(2 ^ bgr)]);
|
|
|
2027 palette[i].green = (png_byte)PNG_sRGB_FROM_LINEAR(255 *
|
|
|
2028 entry[1]);
|
|
|
2029 palette[i].red = (png_byte)PNG_sRGB_FROM_LINEAR(255 *
|
|
|
2030 entry[bgr]);
|
|
|
2031 }
|
|
|
2032
|
|
|
2033 else /* Gray */
|
|
|
2034 palette[i].blue = palette[i].red = palette[i].green =
|
|
|
2035 (png_byte)PNG_sRGB_FROM_LINEAR(255 * *entry);
|
|
|
2036 }
|
|
|
2037
|
|
|
2038 else /* alpha */
|
|
|
2039 {
|
|
|
2040 png_uint_16 alpha = entry[afirst ? 0 : channels-1];
|
|
|
2041 png_byte alphabyte = (png_byte)PNG_DIV257(alpha);
|
|
|
2042 png_uint_32 reciprocal = 0;
|
|
|
2043
|
|
|
2044 /* Calculate a reciprocal, as in the png_write_image_8bit code above
|
|
|
2045 * this is designed to produce a value scaled to 255*65535 when
|
|
|
2046 * divided by 128 (i.e. asr 7).
|
|
|
2047 */
|
|
|
2048 if (alphabyte > 0 && alphabyte < 255)
|
|
|
2049 reciprocal = (((0xffff*0xff)<<7)+(alpha>>1))/alpha;
|
|
|
2050
|
|
|
2051 tRNS[i] = alphabyte;
|
|
|
2052 if (alphabyte < 255)
|
|
|
2053 num_trans = i+1;
|
|
|
2054
|
|
|
2055 if (channels >= 3) /* RGB */
|
|
|
2056 {
|
|
|
2057 palette[i].blue = png_unpremultiply(entry[afirst + (2 ^ bgr)],
|
|
|
2058 alpha, reciprocal);
|
|
|
2059 palette[i].green = png_unpremultiply(entry[afirst + 1], alpha,
|
|
|
2060 reciprocal);
|
|
|
2061 palette[i].red = png_unpremultiply(entry[afirst + bgr], alpha,
|
|
|
2062 reciprocal);
|
|
|
2063 }
|
|
|
2064
|
|
|
2065 else /* gray */
|
|
|
2066 palette[i].blue = palette[i].red = palette[i].green =
|
|
|
2067 png_unpremultiply(entry[afirst], alpha, reciprocal);
|
|
|
2068 }
|
|
|
2069 }
|
|
|
2070
|
|
|
2071 else /* Color-map has sRGB values */
|
|
|
2072 {
|
|
|
2073 png_const_bytep entry = png_voidcast(png_const_bytep, cmap);
|
|
|
2074
|
|
|
2075 entry += i * channels;
|
|
|
2076
|
|
|
2077 switch (channels)
|
|
|
2078 {
|
|
|
2079 case 4:
|
|
|
2080 tRNS[i] = entry[afirst ? 0 : 3];
|
|
|
2081 if (tRNS[i] < 255)
|
|
|
2082 num_trans = i+1;
|
|
|
2083 /* FALL THROUGH */
|
|
|
2084 case 3:
|
|
|
2085 palette[i].blue = entry[afirst + (2 ^ bgr)];
|
|
|
2086 palette[i].green = entry[afirst + 1];
|
|
|
2087 palette[i].red = entry[afirst + bgr];
|
|
|
2088 break;
|
|
|
2089
|
|
|
2090 case 2:
|
|
|
2091 tRNS[i] = entry[1 ^ afirst];
|
|
|
2092 if (tRNS[i] < 255)
|
|
|
2093 num_trans = i+1;
|
|
|
2094 /* FALL THROUGH */
|
|
|
2095 case 1:
|
|
|
2096 palette[i].blue = palette[i].red = palette[i].green =
|
|
|
2097 entry[afirst];
|
|
|
2098 break;
|
|
|
2099
|
|
|
2100 default:
|
|
|
2101 break;
|
|
|
2102 }
|
|
|
2103 }
|
|
|
2104 }
|
|
|
2105
|
|
|
2106 # ifdef afirst
|
|
|
2107 # undef afirst
|
|
|
2108 # endif
|
|
|
2109 # ifdef bgr
|
|
|
2110 # undef bgr
|
|
|
2111 # endif
|
|
|
2112
|
|
|
2113 png_set_PLTE(image->opaque->png_ptr, image->opaque->info_ptr, palette,
|
|
|
2114 entries);
|
|
|
2115
|
|
|
2116 if (num_trans > 0)
|
|
|
2117 png_set_tRNS(image->opaque->png_ptr, image->opaque->info_ptr, tRNS,
|
|
|
2118 num_trans, NULL);
|
|
|
2119
|
|
|
2120 image->colormap_entries = entries;
|
|
|
2121 }
|
|
|
2122
|
|
|
2123 static int
|
|
|
2124 png_image_write_main(png_voidp argument)
|
|
|
2125 {
|
|
|
2126 png_image_write_control *display = png_voidcast(png_image_write_control*,
|
|
|
2127 argument);
|
|
|
2128 png_imagep image = display->image;
|
|
|
2129 png_structrp png_ptr = image->opaque->png_ptr;
|
|
|
2130 png_inforp info_ptr = image->opaque->info_ptr;
|
|
|
2131 png_uint_32 format = image->format;
|
|
|
2132
|
|
|
2133 int colormap = (format & PNG_FORMAT_FLAG_COLORMAP) != 0;
|
|
|
2134 int linear = !colormap && (format & PNG_FORMAT_FLAG_LINEAR) != 0; /* input */
|
|
|
2135 int alpha = !colormap && (format & PNG_FORMAT_FLAG_ALPHA) != 0;
|
|
|
2136 int write_16bit = linear && !colormap && !display->convert_to_8bit;
|
|
|
2137
|
|
|
2138 # ifdef PNG_BENIGN_ERRORS_SUPPORTED
|
|
|
2139 /* Make sure we error out on any bad situation */
|
|
|
2140 png_set_benign_errors(png_ptr, 0/*error*/);
|
|
|
2141 # endif
|
|
|
2142
|
|
|
2143 /* Default the 'row_stride' parameter if required. */
|
|
|
2144 if (display->row_stride == 0)
|
|
|
2145 display->row_stride = PNG_IMAGE_ROW_STRIDE(*image);
|
|
|
2146
|
|
|
2147 /* Set the required transforms then write the rows in the correct order. */
|
|
|
2148 if (format & PNG_FORMAT_FLAG_COLORMAP)
|
|
|
2149 {
|
|
|
2150 if (display->colormap != NULL && image->colormap_entries > 0)
|
|
|
2151 {
|
|
|
2152 png_uint_32 entries = image->colormap_entries;
|
|
|
2153
|
|
|
2154 png_set_IHDR(png_ptr, info_ptr, image->width, image->height,
|
|
|
2155 entries > 16 ? 8 : (entries > 4 ? 4 : (entries > 2 ? 2 : 1)),
|
|
|
2156 PNG_COLOR_TYPE_PALETTE, PNG_INTERLACE_NONE,
|
|
|
2157 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
|
|
|
2158
|
|
|
2159 png_image_set_PLTE(display);
|
|
|
2160 }
|
|
|
2161
|
|
|
2162 else
|
|
|
2163 png_error(image->opaque->png_ptr,
|
|
|
2164 "no color-map for color-mapped image");
|
|
|
2165 }
|
|
|
2166
|
|
|
2167 else
|
|
|
2168 png_set_IHDR(png_ptr, info_ptr, image->width, image->height,
|
|
|
2169 write_16bit ? 16 : 8,
|
|
|
2170 ((format & PNG_FORMAT_FLAG_COLOR) ? PNG_COLOR_MASK_COLOR : 0) +
|
|
|
2171 ((format & PNG_FORMAT_FLAG_ALPHA) ? PNG_COLOR_MASK_ALPHA : 0),
|
|
|
2172 PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
|
|
|
2173
|
|
|
2174 /* Counter-intuitively the data transformations must be called *after*
|
|
|
2175 * png_write_info, not before as in the read code, but the 'set' functions
|
|
|
2176 * must still be called before. Just set the color space information, never
|
|
|
2177 * write an interlaced image.
|
|
|
2178 */
|
|
|
2179
|
|
|
2180 if (write_16bit)
|
|
|
2181 {
|
|
|
2182 /* The gamma here is 1.0 (linear) and the cHRM chunk matches sRGB. */
|
|
|
2183 png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_LINEAR);
|
|
|
2184
|
|
|
2185 if (!(image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB))
|
|
|
2186 png_set_cHRM_fixed(png_ptr, info_ptr,
|
|
|
2187 /* color x y */
|
|
|
2188 /* white */ 31270, 32900,
|
|
|
2189 /* red */ 64000, 33000,
|
|
|
2190 /* green */ 30000, 60000,
|
|
|
2191 /* blue */ 15000, 6000
|
|
|
2192 );
|
|
|
2193 }
|
|
|
2194
|
|
|
2195 else if (!(image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB))
|
|
|
2196 png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_PERCEPTUAL);
|
|
|
2197
|
|
|
2198 /* Else writing an 8-bit file and the *colors* aren't sRGB, but the 8-bit
|
|
|
2199 * space must still be gamma encoded.
|
|
|
2200 */
|
|
|
2201 else
|
|
|
2202 png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_sRGB_INVERSE);
|
|
|
2203
|
|
|
2204 /* Write the file header. */
|
|
|
2205 png_write_info(png_ptr, info_ptr);
|
|
|
2206
|
|
|
2207 /* Now set up the data transformations (*after* the header is written),
|
|
|
2208 * remove the handled transformations from the 'format' flags for checking.
|
|
|
2209 *
|
|
|
2210 * First check for a little endian system if writing 16 bit files.
|
|
|
2211 */
|
|
|
2212 if (write_16bit)
|
|
|
2213 {
|
|
|
2214 PNG_CONST png_uint_16 le = 0x0001;
|
|
|
2215
|
|
|
2216 if (*(png_const_bytep)&le)
|
|
|
2217 png_set_swap(png_ptr);
|
|
|
2218 }
|
|
|
2219
|
|
|
2220 # ifdef PNG_SIMPLIFIED_WRITE_BGR_SUPPORTED
|
|
|
2221 if (format & PNG_FORMAT_FLAG_BGR)
|
|
|
2222 {
|
|
|
2223 if (!colormap && (format & PNG_FORMAT_FLAG_COLOR) != 0)
|
|
|
2224 png_set_bgr(png_ptr);
|
|
|
2225 format &= ~PNG_FORMAT_FLAG_BGR;
|
|
|
2226 }
|
|
|
2227 # endif
|
|
|
2228
|
|
|
2229 # ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
|
|
|
2230 if (format & PNG_FORMAT_FLAG_AFIRST)
|
|
|
2231 {
|
|
|
2232 if (!colormap && (format & PNG_FORMAT_FLAG_ALPHA) != 0)
|
|
|
2233 png_set_swap_alpha(png_ptr);
|
|
|
2234 format &= ~PNG_FORMAT_FLAG_AFIRST;
|
|
|
2235 }
|
|
|
2236 # endif
|
|
|
2237
|
|
|
2238 /* If there are 16 or fewer color-map entries we wrote a lower bit depth
|
|
|
2239 * above, but the application data is still byte packed.
|
|
|
2240 */
|
|
|
2241 if (colormap && image->colormap_entries <= 16)
|
|
|
2242 png_set_packing(png_ptr);
|
|
|
2243
|
|
|
2244 /* That should have handled all (both) the transforms. */
|
|
|
2245 if ((format & ~(png_uint_32)(PNG_FORMAT_FLAG_COLOR | PNG_FORMAT_FLAG_LINEAR |
|
|
|
2246 PNG_FORMAT_FLAG_ALPHA | PNG_FORMAT_FLAG_COLORMAP)) != 0)
|
|
|
2247 png_error(png_ptr, "png_write_image: unsupported transformation");
|
|
|
2248
|
|
|
2249 {
|
|
|
2250 png_const_bytep row = png_voidcast(png_const_bytep, display->buffer);
|
|
|
2251 ptrdiff_t row_bytes = display->row_stride;
|
|
|
2252
|
|
|
2253 if (linear)
|
|
|
2254 row_bytes *= (sizeof (png_uint_16));
|
|
|
2255
|
|
|
2256 if (row_bytes < 0)
|
|
|
2257 row += (image->height-1) * (-row_bytes);
|
|
|
2258
|
|
|
2259 display->first_row = row;
|
|
|
2260 display->row_bytes = row_bytes;
|
|
|
2261 }
|
|
|
2262
|
|
|
2263 /* Apply 'fast' options if the flag is set. */
|
|
|
2264 if ((image->flags & PNG_IMAGE_FLAG_FAST) != 0)
|
|
|
2265 {
|
|
|
2266 png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, PNG_NO_FILTERS);
|
|
|
2267 /* NOTE: determined by experiment using pngstest, this reflects some
|
|
|
2268 * balance between the time to write the image once and the time to read
|
|
|
2269 * it about 50 times. The speed-up in pngstest was about 10-20% of the
|
|
|
2270 * total (user) time on a heavily loaded system.
|
|
|
2271 */
|
|
|
2272 png_set_compression_level(png_ptr, 3);
|
|
|
2273 }
|
|
|
2274
|
|
|
2275 /* Check for the cases that currently require a pre-transform on the row
|
|
|
2276 * before it is written. This only applies when the input is 16-bit and
|
|
|
2277 * either there is an alpha channel or it is converted to 8-bit.
|
|
|
2278 */
|
|
|
2279 if ((linear && alpha) || (!colormap && display->convert_to_8bit))
|
|
|
2280 {
|
|
|
2281 png_bytep row = png_voidcast(png_bytep, png_malloc(png_ptr,
|
|
|
2282 png_get_rowbytes(png_ptr, info_ptr)));
|
|
|
2283 int result;
|
|
|
2284
|
|
|
2285 display->local_row = row;
|
|
|
2286 if (write_16bit)
|
|
|
2287 result = png_safe_execute(image, png_write_image_16bit, display);
|
|
|
2288 else
|
|
|
2289 result = png_safe_execute(image, png_write_image_8bit, display);
|
|
|
2290 display->local_row = NULL;
|
|
|
2291
|
|
|
2292 png_free(png_ptr, row);
|
|
|
2293
|
|
|
2294 /* Skip the 'write_end' on error: */
|
|
|
2295 if (!result)
|
|
|
2296 return 0;
|
|
|
2297 }
|
|
|
2298
|
|
|
2299 /* Otherwise this is the case where the input is in a format currently
|
|
|
2300 * supported by the rest of the libpng write code; call it directly.
|
|
|
2301 */
|
|
|
2302 else
|
|
|
2303 {
|
|
|
2304 png_const_bytep row = png_voidcast(png_const_bytep, display->first_row);
|
|
|
2305 ptrdiff_t row_bytes = display->row_bytes;
|
|
|
2306 png_uint_32 y = image->height;
|
|
|
2307
|
|
|
2308 while (y-- > 0)
|
|
|
2309 {
|
|
|
2310 png_write_row(png_ptr, row);
|
|
|
2311 row += row_bytes;
|
|
|
2312 }
|
|
|
2313 }
|
|
|
2314
|
|
|
2315 png_write_end(png_ptr, info_ptr);
|
|
|
2316 return 1;
|
|
|
2317 }
|
|
|
2318
|
|
|
2319 int PNGAPI
|
|
|
2320 png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
|
|
|
2321 const void *buffer, png_int_32 row_stride, const void *colormap)
|
|
|
2322 {
|
|
|
2323 /* Write the image to the given (FILE*). */
|
|
|
2324 if (image != NULL && image->version == PNG_IMAGE_VERSION)
|
|
|
2325 {
|
|
|
2326 if (file != NULL)
|
|
|
2327 {
|
|
|
2328 if (png_image_write_init(image))
|
|
|
2329 {
|
|
|
2330 png_image_write_control display;
|
|
|
2331 int result;
|
|
|
2332
|
|
|
2333 /* This is slightly evil, but png_init_io doesn't do anything other
|
|
|
2334 * than this and we haven't changed the standard IO functions so
|
|
|
2335 * this saves a 'safe' function.
|
|
|
2336 */
|
|
|
2337 image->opaque->png_ptr->io_ptr = file;
|
|
|
2338
|
|
|
2339 memset(&display, 0, (sizeof display));
|
|
|
2340 display.image = image;
|
|
|
2341 display.buffer = buffer;
|
|
|
2342 display.row_stride = row_stride;
|
|
|
2343 display.colormap = colormap;
|
|
|
2344 display.convert_to_8bit = convert_to_8bit;
|
|
|
2345
|
|
|
2346 result = png_safe_execute(image, png_image_write_main, &display);
|
|
|
2347 png_image_free(image);
|
|
|
2348 return result;
|
|
|
2349 }
|
|
|
2350
|
|
|
2351 else
|
|
|
2352 return 0;
|
|
|
2353 }
|
|
|
2354
|
|
|
2355 else
|
|
|
2356 return png_image_error(image,
|
|
|
2357 "png_image_write_to_stdio: invalid argument");
|
|
|
2358 }
|
|
|
2359
|
|
|
2360 else if (image != NULL)
|
|
|
2361 return png_image_error(image,
|
|
|
2362 "png_image_write_to_stdio: incorrect PNG_IMAGE_VERSION");
|
|
|
2363
|
|
|
2364 else
|
|
|
2365 return 0;
|
|
|
2366 }
|
|
|
2367
|
|
|
2368 int PNGAPI
|
|
|
2369 png_image_write_to_file(png_imagep image, const char *file_name,
|
|
|
2370 int convert_to_8bit, const void *buffer, png_int_32 row_stride,
|
|
|
2371 const void *colormap)
|
|
|
2372 {
|
|
|
2373 /* Write the image to the named file. */
|
|
|
2374 if (image != NULL && image->version == PNG_IMAGE_VERSION)
|
|
|
2375 {
|
|
|
2376 if (file_name != NULL)
|
|
|
2377 {
|
|
|
2378 FILE *fp = fopen(file_name, "wb");
|
|
|
2379
|
|
|
2380 if (fp != NULL)
|
|
|
2381 {
|
|
|
2382 if (png_image_write_to_stdio(image, fp, convert_to_8bit, buffer,
|
|
|
2383 row_stride, colormap))
|
|
|
2384 {
|
|
|
2385 int error; /* from fflush/fclose */
|
|
|
2386
|
|
|
2387 /* Make sure the file is flushed correctly. */
|
|
|
2388 if (fflush(fp) == 0 && ferror(fp) == 0)
|
|
|
2389 {
|
|
|
2390 if (fclose(fp) == 0)
|
|
|
2391 return 1;
|
|
|
2392
|
|
|
2393 error = errno; /* from fclose */
|
|
|
2394 }
|
|
|
2395
|
|
|
2396 else
|
|
|
2397 {
|
|
|
2398 error = errno; /* from fflush or ferror */
|
|
|
2399 (void)fclose(fp);
|
|
|
2400 }
|
|
|
2401
|
|
|
2402 (void)remove(file_name);
|
|
|
2403 /* The image has already been cleaned up; this is just used to
|
|
|
2404 * set the error (because the original write succeeded).
|
|
|
2405 */
|
|
|
2406 return png_image_error(image, strerror(error));
|
|
|
2407 }
|
|
|
2408
|
|
|
2409 else
|
|
|
2410 {
|
|
|
2411 /* Clean up: just the opened file. */
|
|
|
2412 (void)fclose(fp);
|
|
|
2413 (void)remove(file_name);
|
|
|
2414 return 0;
|
|
|
2415 }
|
|
|
2416 }
|
|
|
2417
|
|
|
2418 else
|
|
|
2419 return png_image_error(image, strerror(errno));
|
|
|
2420 }
|
|
|
2421
|
|
|
2422 else
|
|
|
2423 return png_image_error(image,
|
|
|
2424 "png_image_write_to_file: invalid argument");
|
|
|
2425 }
|
|
|
2426
|
|
|
2427 else if (image != NULL)
|
|
|
2428 return png_image_error(image,
|
|
|
2429 "png_image_write_to_file: incorrect PNG_IMAGE_VERSION");
|
|
|
2430
|
|
|
2431 else
|
|
|
2432 return 0;
|
|
|
2433 }
|
|
|
2434 #endif /* PNG_STDIO_SUPPORTED */
|
|
|
2435 #endif /* SIMPLIFIED_WRITE */
|
|
|
2436 #endif /* PNG_WRITE_SUPPORTED */
|
