SDL-1.2.14
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81 >Chapter 10. Audio</H1
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
93 >&nbsp;--&nbsp;Audio Specification Structure</DT
94 ><DT
95 ><A
96 HREF="sdlopenaudio.html"
97 >SDL_OpenAudio</A
98 >&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
99 ><DT
100 ><A
101 HREF="sdlpauseaudio.html"
102 >SDL_PauseAudio</A
103 >&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
104 ><DT
105 ><A
106 HREF="sdlgetaudiostatus.html"
107 >SDL_GetAudioStatus</A
108 >&nbsp;--&nbsp;Get the current audio state</DT
109 ><DT
110 ><A
111 HREF="sdlloadwav.html"
112 >SDL_LoadWAV</A
113 >&nbsp;--&nbsp;Load a WAVE file</DT
114 ><DT
115 ><A
116 HREF="sdlfreewav.html"
117 >SDL_FreeWAV</A
118 >&nbsp;--&nbsp;Frees previously opened WAV data</DT
119 ><DT
120 ><A
121 HREF="sdlaudiocvt.html"
122 >SDL_AudioCVT</A
123 >&nbsp;--&nbsp;Audio Conversion Structure</DT
124 ><DT
125 ><A
126 HREF="sdlbuildaudiocvt.html"
127 >SDL_BuildAudioCVT</A
128 >&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
129 ><DT
130 ><A
131 HREF="sdlconvertaudio.html"
132 >SDL_ConvertAudio</A
133 >&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
134 ><DT
135 ><A
136 HREF="sdlmixaudio.html"
137 >SDL_MixAudio</A
138 >&nbsp;--&nbsp;Mix audio data</DT
139 ><DT
140 ><A
141 HREF="sdllockaudio.html"
142 >SDL_LockAudio</A
143 >&nbsp;--&nbsp;Lock out the callback function</DT
144 ><DT
145 ><A
146 HREF="sdlunlockaudio.html"
147 >SDL_UnlockAudio</A
148 >&nbsp;--&nbsp;Unlock the callback function</DT
149 ><DT
150 ><A
151 HREF="sdlcloseaudio.html"
152 >SDL_CloseAudio</A
153 >&nbsp;--&nbsp;Shuts down audio processing and closes the audio device.</DT
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
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