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comparison decoders/mpglib/mpglib_common.c @ 298:c92c07e07636

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Renamed from common.c.
author Ryan C. Gordon <icculus@icculus.org>
date Mon, 25 Mar 2002 20:51:32 +0000
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children 31cc49d7d0ce
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297:e8d9255f1a42 298:c92c07e07636
1 #include <ctype.h>
2 #include <stdlib.h>
3 #include <signal.h>
4
5 #include <sys/types.h>
6 #include <sys/stat.h>
7 #include <fcntl.h>
8
9 #include "SDL_sound.h"
10
11 #define __SDL_SOUND_INTERNAL__
12 #include "SDL_sound_internal.h"
13
14 #include "mpg123_sdlsound.h"
15
16 struct parameter param = { 1 , 1 , 0 , 0 };
17
18 int tabsel_123[2][3][16] = {
19 { {0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,},
20 {0,32,48,56, 64, 80, 96,112,128,160,192,224,256,320,384,},
21 {0,32,40,48, 56, 64, 80, 96,112,128,160,192,224,256,320,} },
22
23 { {0,32,48,56,64,80,96,112,128,144,160,176,192,224,256,},
24 {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,},
25 {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,} }
26 };
27
28 long mpglib_freqs[9] = { 44100, 48000, 32000,
29 22050, 24000, 16000 ,
30 11025 , 12000 , 8000 };
31
32 int bitindex;
33 unsigned char *wordpointer;
34 unsigned char *pcm_sample;
35 int pcm_point = 0;
36
37
38 #define HDRCMPMASK 0xfffffd00
39
40 #if 0
41 int head_check(unsigned long head)
42 {
43 if( (head & 0xffe00000) != 0xffe00000)
44 return FALSE;
45 if(!((head>>17)&3))
46 return FALSE;
47 if( ((head>>12)&0xf) == 0xf)
48 return FALSE;
49 if( ((head>>10)&0x3) == 0x3 )
50 return FALSE;
51 return TRUE;
52 }
53 #endif
54
55
56 /*
57 * the code a header and write the information
58 * into the frame structure
59 */
60 int decode_header(struct frame *fr,unsigned long newhead)
61 {
62 if( newhead & (1<<20) ) {
63 fr->lsf = (newhead & (1<<19)) ? 0x0 : 0x1;
64 fr->mpeg25 = 0;
65 }
66 else {
67 fr->lsf = 1;
68 fr->mpeg25 = 1;
69 }
70
71 fr->lay = 4-((newhead>>17)&3);
72 if( ((newhead>>10)&0x3) == 0x3) {
73 Sound_SetError("MPGLIB: Corrupted header");
74 return 0;
75 }
76 if(fr->mpeg25) {
77 fr->sampling_frequency = 6 + ((newhead>>10)&0x3);
78 }
79 else
80 fr->sampling_frequency = ((newhead>>10)&0x3) + (fr->lsf*3);
81 fr->error_protection = ((newhead>>16)&0x1)^0x1;
82
83 if(fr->mpeg25) /* allow Bitrate change for 2.5 ... */
84 fr->bitrate_index = ((newhead>>12)&0xf);
85
86 fr->bitrate_index = ((newhead>>12)&0xf);
87 fr->padding = ((newhead>>9)&0x1);
88 fr->extension = ((newhead>>8)&0x1);
89 fr->mode = ((newhead>>6)&0x3);
90 fr->mode_ext = ((newhead>>4)&0x3);
91 fr->copyright = ((newhead>>3)&0x1);
92 fr->original = ((newhead>>2)&0x1);
93 fr->emphasis = newhead & 0x3;
94
95 fr->stereo = (fr->mode == MPG_MD_MONO) ? 1 : 2;
96
97 if(!fr->bitrate_index)
98 {
99 Sound_SetError("MPGLIB: Free format not supported.");
100 return (0);
101 }
102
103 switch(fr->lay)
104 {
105 case 1:
106 #ifdef LAYER1
107 #if 0
108 fr->jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ?
109 (fr->mode_ext<<2)+4 : 32;
110 #endif
111 fr->framesize = (long) tabsel_123[fr->lsf][0][fr->bitrate_index] * 12000;
112 fr->framesize /= mpglib_freqs[fr->sampling_frequency];
113 fr->framesize = ((fr->framesize+fr->padding)<<2)-4;
114 #else
115 Sound_SetError("MPGLIB: Not supported!");
116 #endif
117 break;
118 case 2:
119 #ifdef LAYER2
120 #if 0
121 fr->jsbound = (fr->mode == MPG_MD_JOINT_STEREO) ?
122 (fr->mode_ext<<2)+4 : fr->II_sblimit;
123 #endif
124 fr->framesize = (long) tabsel_123[fr->lsf][1][fr->bitrate_index] * 144000;
125 fr->framesize /= mpglib_freqs[fr->sampling_frequency];
126 fr->framesize += fr->padding - 4;
127 #else
128 Sound_SetError("MPGLIB: Not supported!");
129 #endif
130 break;
131 case 3:
132 #if 0
133 fr->do_layer = do_layer3;
134 if(fr->lsf)
135 ssize = (fr->stereo == 1) ? 9 : 17;
136 else
137 ssize = (fr->stereo == 1) ? 17 : 32;
138 #endif
139
140 #if 0
141 if(fr->error_protection)
142 ssize += 2;
143 #endif
144 fr->framesize = (long) tabsel_123[fr->lsf][2][fr->bitrate_index] * 144000;
145 fr->framesize /= mpglib_freqs[fr->sampling_frequency]<<(fr->lsf);
146 fr->framesize = fr->framesize + fr->padding - 4;
147 break;
148 default:
149 Sound_SetError("MPGLIB: Unknown layer type.");
150 return (0);
151 }
152 return 1;
153 }
154
155 #if 0
156 void print_header(struct frame *fr)
157 {
158 static char *modes[4] = { "Stereo", "Joint-Stereo", "Dual-Channel", "Single-Channel" };
159 static char *layers[4] = { "Unknown" , "I", "II", "III" };
160
161 fprintf(stderr,"MPEG %s, Layer: %s, Freq: %ld, mode: %s, modext: %d, BPF : %d\n",
162 fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"),
163 layers[fr->lay],mpglib_freqs[fr->sampling_frequency],
164 modes[fr->mode],fr->mode_ext,fr->framesize+4);
165 fprintf(stderr,"Channels: %d, copyright: %s, original: %s, CRC: %s, emphasis: %d.\n",
166 fr->stereo,fr->copyright?"Yes":"No",
167 fr->original?"Yes":"No",fr->error_protection?"Yes":"No",
168 fr->emphasis);
169 fprintf(stderr,"Bitrate: %d Kbits/s, Extension value: %d\n",
170 tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index],fr->extension);
171 }
172
173 void print_header_compact(struct frame *fr)
174 {
175 static char *modes[4] = { "stereo", "joint-stereo", "dual-channel", "mono" };
176 static char *layers[4] = { "Unknown" , "I", "II", "III" };
177
178 fprintf(stderr,"MPEG %s layer %s, %d kbit/s, %ld Hz %s\n",
179 fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"),
180 layers[fr->lay],
181 tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index],
182 mpglib_freqs[fr->sampling_frequency], modes[fr->mode]);
183 }
184
185 #endif
186
187 unsigned int getbits(int number_of_bits)
188 {
189 unsigned long rval;
190
191 if(!number_of_bits)
192 return 0;
193
194 {
195 rval = wordpointer[0];
196 rval <<= 8;
197 rval |= wordpointer[1];
198 rval <<= 8;
199 rval |= wordpointer[2];
200 rval <<= bitindex;
201 rval &= 0xffffff;
202
203 bitindex += number_of_bits;
204
205 rval >>= (24-number_of_bits);
206
207 wordpointer += (bitindex>>3);
208 bitindex &= 7;
209 }
210 return rval;
211 }
212
213 unsigned int getbits_fast(int number_of_bits)
214 {
215 unsigned long rval;
216
217 {
218 rval = wordpointer[0];
219 rval <<= 8;
220 rval |= wordpointer[1];
221 rval <<= bitindex;
222 rval &= 0xffff;
223 bitindex += number_of_bits;
224
225 rval >>= (16-number_of_bits);
226
227 wordpointer += (bitindex>>3);
228 bitindex &= 7;
229 }
230 return rval;
231 }
232
233 unsigned int get1bit(void)
234 {
235 unsigned char rval;
236 rval = *wordpointer << bitindex;
237
238 bitindex++;
239 wordpointer += (bitindex>>3);
240 bitindex &= 7;
241
242 return rval>>7;
243 }
244
245
246