[sdl_omap.git] / docs / html / audio.html

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><DIV
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>Chapter 10. Audio</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlaudiospec.html"
>SDL_AudioSpec</A
>&nbsp;--&nbsp;Audio Specification Structure</DT
><DT
><A
HREF="sdlopenaudio.html"
>SDL_OpenAudio</A
>&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
><DT
><A
HREF="sdlpauseaudio.html"
>SDL_PauseAudio</A
>&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
><DT
><A
HREF="sdlgetaudiostatus.html"
>SDL_GetAudioStatus</A
>&nbsp;--&nbsp;Get the current audio state</DT
><DT
><A
HREF="sdlloadwav.html"
>SDL_LoadWAV</A
>&nbsp;--&nbsp;Load a WAVE file</DT
><DT
><A
HREF="sdlfreewav.html"
>SDL_FreeWAV</A
>&nbsp;--&nbsp;Frees previously opened WAV data</DT
><DT
><A
HREF="sdlaudiocvt.html"
>SDL_AudioCVT</A
>&nbsp;--&nbsp;Audio Conversion Structure</DT
><DT
><A
HREF="sdlbuildaudiocvt.html"
>SDL_BuildAudioCVT</A
>&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
><DT
><A
HREF="sdlconvertaudio.html"
>SDL_ConvertAudio</A
>&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
><DT
><A
HREF="sdlmixaudio.html"
>SDL_MixAudio</A
>&nbsp;--&nbsp;Mix audio data</DT
><DT
><A
HREF="sdllockaudio.html"
>SDL_LockAudio</A
>&nbsp;--&nbsp;Lock out the callback function</DT
><DT
><A
HREF="sdlunlockaudio.html"
>SDL_UnlockAudio</A
>&nbsp;--&nbsp;Unlock the callback function</DT
><DT
><A
HREF="sdlcloseaudio.html"
>SDL_CloseAudio</A
>&nbsp;--&nbsp;Shuts down audio processing and closes the audio device.</DT
></DL
></DIV
><P
>Sound on the computer is translated from waves that you hear into a series of 
values, or samples, each representing the amplitude of the wave.  When these
samples are sent in a stream to a sound card, an approximation of the original
wave can be recreated.  The more bits used to represent the amplitude, and the
greater frequency these samples are gathered, the closer the approximated
sound is to the original, and the better the quality of sound.</P
><P
>This library supports both 8 and 16 bit signed and unsigned sound samples,
at frequencies ranging from 11025 Hz to 44100 Hz, depending on the 
underlying hardware.  If the hardware doesn't support the desired audio
format or frequency, it can be emulated if desired (See 
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio()</TT
></A
>)</P
><P
>A commonly supported audio format is 16 bits per sample at 22050 Hz.</P
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Commit	Line	Data
e14743d1	1	<HTML
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	4	>Audio</TITLE
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	44	>SDL Library Documentation</TH
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66	HREF="sdlaudiospec.html"
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68	>Next</A
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75	><DIV
76	CLASS="CHAPTER"
77	><H1
78	><A
79	NAME="AUDIO"
80	></A
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	> -- Audio Specification Structure</DT
94	><DT
95	><A
96	HREF="sdlopenaudio.html"
97	>SDL_OpenAudio</A
98	> -- Opens the audio device with the desired parameters.</DT
99	><DT
100	><A
101	HREF="sdlpauseaudio.html"
102	>SDL_PauseAudio</A
103	> -- Pauses and unpauses the audio callback processing</DT
104	><DT
105	><A
106	HREF="sdlgetaudiostatus.html"
107	>SDL_GetAudioStatus</A
108	> -- Get the current audio state</DT
109	><DT
110	><A
111	HREF="sdlloadwav.html"
112	>SDL_LoadWAV</A
113	> -- Load a WAVE file</DT
114	><DT
115	><A
116	HREF="sdlfreewav.html"
117	>SDL_FreeWAV</A
118	> -- Frees previously opened WAV data</DT
119	><DT
120	><A
121	HREF="sdlaudiocvt.html"
122	>SDL_AudioCVT</A
123	> -- Audio Conversion Structure</DT
124	><DT
125	><A
126	HREF="sdlbuildaudiocvt.html"
127	>SDL_BuildAudioCVT</A
128	> -- Initializes a SDL_AudioCVT structure for conversion</DT
129	><DT
130	><A
131	HREF="sdlconvertaudio.html"
132	>SDL_ConvertAudio</A
133	> -- Convert audio data to a desired audio format.</DT
134	><DT
135	><A
136	HREF="sdlmixaudio.html"
137	>SDL_MixAudio</A
138	> -- Mix audio data</DT
139	><DT
140	><A
141	HREF="sdllockaudio.html"
142	>SDL_LockAudio</A
143	> -- Lock out the callback function</DT
144	><DT
145	><A
146	HREF="sdlunlockaudio.html"
147	>SDL_UnlockAudio</A
148	> -- Unlock the callback function</DT
149	><DT
150	><A
151	HREF="sdlcloseaudio.html"
152	>SDL_CloseAudio</A
153	> -- 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
177	></DIV
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236	>SDL_AudioSpec</TD
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242	>