Mercurial > sdl-ios-xcode
annotate docs/html/audio.html @ 4355:9b464226e541 SDL-1.2
Fixed bug #855
Ludwig Nussel 2009-10-18 06:31:52 PDT
an mprotect call was added to fix bug 528. However that results in a buffer
that allows writing and code execution. Ie the no-execute security features of
modern operating systems are defeated this way. Two mprotect calls are needed.
One to make the buffer executable but not writeable when done and another one
to make the buffer writeable again if the content needs to be changed.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sun, 18 Oct 2009 17:31:37 +0000 |
| parents | 355632dca928 |
| children |
| rev | line source |
|---|---|
| 0 | 1 <HTML |
| 2 ><HEAD | |
| 3 ><TITLE | |
| 4 >Audio</TITLE | |
| 5 ><META | |
| 6 NAME="GENERATOR" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
7 CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ |
| 0 | 8 "><LINK |
| 9 REL="HOME" | |
| 10 TITLE="SDL Library Documentation" | |
| 11 HREF="index.html"><LINK | |
| 12 REL="UP" | |
| 13 TITLE="SDL Reference" | |
| 14 HREF="reference.html"><LINK | |
| 15 REL="PREVIOUS" | |
| 16 TITLE="SDL_JoystickClose" | |
| 17 HREF="sdljoystickclose.html"><LINK | |
| 18 REL="NEXT" | |
| 19 TITLE="SDL_AudioSpec" | |
| 20 HREF="sdlaudiospec.html"><META | |
| 21 NAME="KEYWORD" | |
| 22 CONTENT="audio"><META | |
| 23 NAME="KEYWORD" | |
| 24 CONTENT="function"></HEAD | |
| 25 ><BODY | |
| 26 CLASS="CHAPTER" | |
| 27 BGCOLOR="#FFF8DC" | |
| 28 TEXT="#000000" | |
| 29 LINK="#0000ee" | |
| 30 VLINK="#551a8b" | |
| 31 ALINK="#ff0000" | |
| 32 ><DIV | |
| 33 CLASS="NAVHEADER" | |
| 34 ><TABLE | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
35 SUMMARY="Header navigation table" |
| 0 | 36 WIDTH="100%" |
| 37 BORDER="0" | |
| 38 CELLPADDING="0" | |
| 39 CELLSPACING="0" | |
| 40 ><TR | |
| 41 ><TH | |
| 42 COLSPAN="3" | |
| 43 ALIGN="center" | |
| 44 >SDL Library Documentation</TH | |
| 45 ></TR | |
| 46 ><TR | |
| 47 ><TD | |
| 48 WIDTH="10%" | |
| 49 ALIGN="left" | |
| 50 VALIGN="bottom" | |
| 51 ><A | |
| 52 HREF="sdljoystickclose.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
53 ACCESSKEY="P" |
| 0 | 54 >Prev</A |
| 55 ></TD | |
| 56 ><TD | |
| 57 WIDTH="80%" | |
| 58 ALIGN="center" | |
| 59 VALIGN="bottom" | |
| 60 ></TD | |
| 61 ><TD | |
| 62 WIDTH="10%" | |
| 63 ALIGN="right" | |
| 64 VALIGN="bottom" | |
| 65 ><A | |
| 66 HREF="sdlaudiospec.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
67 ACCESSKEY="N" |
| 0 | 68 >Next</A |
| 69 ></TD | |
| 70 ></TR | |
| 71 ></TABLE | |
| 72 ><HR | |
| 73 ALIGN="LEFT" | |
| 74 WIDTH="100%"></DIV | |
| 75 ><DIV | |
| 76 CLASS="CHAPTER" | |
| 77 ><H1 | |
| 78 ><A | |
| 79 NAME="AUDIO" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
80 ></A |
|
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
81 >Chapter 10. Audio</H1 |
| 0 | 82 ><DIV |
| 83 CLASS="TOC" | |
| 84 ><DL | |
| 85 ><DT | |
| 86 ><B | |
| 87 >Table of Contents</B | |
| 88 ></DT | |
| 89 ><DT | |
| 90 ><A | |
| 91 HREF="sdlaudiospec.html" | |
| 92 >SDL_AudioSpec</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
93 > -- Audio Specification Structure</DT |
| 0 | 94 ><DT |
| 95 ><A | |
| 96 HREF="sdlopenaudio.html" | |
| 97 >SDL_OpenAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
98 > -- Opens the audio device with the desired parameters.</DT |
| 0 | 99 ><DT |
| 100 ><A | |
| 101 HREF="sdlpauseaudio.html" | |
| 102 >SDL_PauseAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
103 > -- Pauses and unpauses the audio callback processing</DT |
| 0 | 104 ><DT |
| 105 ><A | |
| 106 HREF="sdlgetaudiostatus.html" | |
| 107 >SDL_GetAudioStatus</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
108 > -- Get the current audio state</DT |
| 0 | 109 ><DT |
| 110 ><A | |
| 111 HREF="sdlloadwav.html" | |
| 112 >SDL_LoadWAV</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
113 > -- Load a WAVE file</DT |
| 0 | 114 ><DT |
| 115 ><A | |
| 116 HREF="sdlfreewav.html" | |
| 117 >SDL_FreeWAV</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
118 > -- Frees previously opened WAV data</DT |
| 0 | 119 ><DT |
| 120 ><A | |
| 121 HREF="sdlaudiocvt.html" | |
| 122 >SDL_AudioCVT</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
123 > -- Audio Conversion Structure</DT |
| 0 | 124 ><DT |
| 125 ><A | |
| 126 HREF="sdlbuildaudiocvt.html" | |
| 127 >SDL_BuildAudioCVT</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
128 > -- Initializes a SDL_AudioCVT structure for conversion</DT |
| 0 | 129 ><DT |
| 130 ><A | |
| 131 HREF="sdlconvertaudio.html" | |
| 132 >SDL_ConvertAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
133 > -- Convert audio data to a desired audio format.</DT |
| 0 | 134 ><DT |
| 135 ><A | |
| 136 HREF="sdlmixaudio.html" | |
| 137 >SDL_MixAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
138 > -- Mix audio data</DT |
| 0 | 139 ><DT |
| 140 ><A | |
| 141 HREF="sdllockaudio.html" | |
| 142 >SDL_LockAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
143 > -- Lock out the callback function</DT |
| 0 | 144 ><DT |
| 145 ><A | |
| 146 HREF="sdlunlockaudio.html" | |
| 147 >SDL_UnlockAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
148 > -- Unlock the callback function</DT |
| 0 | 149 ><DT |
| 150 ><A | |
| 151 HREF="sdlcloseaudio.html" | |
| 152 >SDL_CloseAudio</A | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
153 > -- Shuts down audio processing and closes the audio device.</DT |
| 0 | 154 ></DL |
| 155 ></DIV | |
| 156 ><P | |
| 157 >Sound on the computer is translated from waves that you hear into a series of | |
| 158 values, or samples, each representing the amplitude of the wave. When these | |
| 159 samples are sent in a stream to a sound card, an approximation of the original | |
| 160 wave can be recreated. The more bits used to represent the amplitude, and the | |
| 161 greater frequency these samples are gathered, the closer the approximated | |
| 162 sound is to the original, and the better the quality of sound.</P | |
| 163 ><P | |
| 164 >This library supports both 8 and 16 bit signed and unsigned sound samples, | |
| 165 at frequencies ranging from 11025 Hz to 44100 Hz, depending on the | |
| 166 underlying hardware. If the hardware doesn't support the desired audio | |
| 167 format or frequency, it can be emulated if desired (See | |
| 168 <A | |
| 169 HREF="sdlopenaudio.html" | |
| 170 ><TT | |
| 171 CLASS="FUNCTION" | |
| 172 >SDL_OpenAudio()</TT | |
| 173 ></A | |
| 174 >)</P | |
| 175 ><P | |
| 176 >A commonly supported audio format is 16 bits per sample at 22050 Hz.</P | |
| 177 ></DIV | |
| 178 ><DIV | |
| 179 CLASS="NAVFOOTER" | |
| 180 ><HR | |
| 181 ALIGN="LEFT" | |
| 182 WIDTH="100%"><TABLE | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
183 SUMMARY="Footer navigation table" |
| 0 | 184 WIDTH="100%" |
| 185 BORDER="0" | |
| 186 CELLPADDING="0" | |
| 187 CELLSPACING="0" | |
| 188 ><TR | |
| 189 ><TD | |
| 190 WIDTH="33%" | |
| 191 ALIGN="left" | |
| 192 VALIGN="top" | |
| 193 ><A | |
| 194 HREF="sdljoystickclose.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
195 ACCESSKEY="P" |
| 0 | 196 >Prev</A |
| 197 ></TD | |
| 198 ><TD | |
| 199 WIDTH="34%" | |
| 200 ALIGN="center" | |
| 201 VALIGN="top" | |
| 202 ><A | |
| 203 HREF="index.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
204 ACCESSKEY="H" |
| 0 | 205 >Home</A |
| 206 ></TD | |
| 207 ><TD | |
| 208 WIDTH="33%" | |
| 209 ALIGN="right" | |
| 210 VALIGN="top" | |
| 211 ><A | |
| 212 HREF="sdlaudiospec.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
213 ACCESSKEY="N" |
| 0 | 214 >Next</A |
| 215 ></TD | |
| 216 ></TR | |
| 217 ><TR | |
| 218 ><TD | |
| 219 WIDTH="33%" | |
| 220 ALIGN="left" | |
| 221 VALIGN="top" | |
| 222 >SDL_JoystickClose</TD | |
| 223 ><TD | |
| 224 WIDTH="34%" | |
| 225 ALIGN="center" | |
| 226 VALIGN="top" | |
| 227 ><A | |
| 228 HREF="reference.html" | |
|
803
355632dca928
Updated SDL HTML documentation
Sam Lantinga <slouken@libsdl.org>
parents:
55
diff
changeset
|
229 ACCESSKEY="U" |
| 0 | 230 >Up</A |
| 231 ></TD | |
| 232 ><TD | |
| 233 WIDTH="33%" | |
| 234 ALIGN="right" | |
| 235 VALIGN="top" | |
| 236 >SDL_AudioSpec</TD | |
| 237 ></TR | |
| 238 ></TABLE | |
| 239 ></DIV | |
| 240 ></BODY | |
| 241 ></HTML | |
| 242 > |