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First shot at new audio data types (int32 and float32). Notable changes: - Converters between types are autogenerated. Instead of making multiple passes over the data with seperate filters for endianess, size, signedness, etc, converting between data types is always one specialized filter. This simplifies SDL_BuildAudioCVT(), which otherwise had a million edge cases with the new types, and makes the actually conversions more CPU cache friendly. Left a stub for adding specific optimized versions of these routines (SSE/MMX/Altivec, assembler, etc) - Autogenerated converters are built by SDL/src/audio/sdlgenaudiocvt.pl. This does not need to be run unless tweaking the code, and thus doesn't need integration into the build system. - Went through all the drivers and tried to weed out all the "Uint16" references that are better specified with the new SDL_AudioFormat typedef. - Cleaned out a bunch of hardcoded bitwise magic numbers and replaced them with new SDL_AUDIO_* macros. - Added initial float32 and int32 support code. Theoretically, existing drivers will push these through converters to get the data they want to feed to the hardware. Still TODO: - Optimize and debug new converters. - Update the CoreAudio backend to accept float32 data directly. - Other backends, too? - SDL_LoadWAV() needs to be updated to support int32 and float32 .wav files (both of which exist and can be generated by 'sox' for testing purposes). - Update the mixer to handle new datatypes. - Optionally update SDL_sound and SDL_mixer, etc.
author Ryan C. Gordon <icculus@icculus.org>
date Thu, 24 Aug 2006 12:10:46 +0000 (2006-08-24)
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_LoadWAV</TITLE
><META
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"><LINK
REL="HOME"
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><H1
><A
NAME="SDLLOADWAV"
></A
>SDL_LoadWAV</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN6816"
></A
><H2
>Name</H2
>SDL_LoadWAV&nbsp;--&nbsp;Load a WAVE file</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN6819"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN6820"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_AudioSpec *<B
CLASS="FSFUNC"
>SDL_LoadWAV</B
></CODE
>(const char *file, SDL_AudioSpec *spec, Uint8 **audio_buf, Uint32 *audio_len);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6826"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
>
This function loads a WAVE <TT
CLASS="PARAMETER"
><I
>file</I
></TT
> into memory.</P
><P
>If this function succeeds, it returns the given 
<A
HREF="sdlaudiospec.html"
><TT
CLASS="FUNCTION"
>SDL_AudioSpec</TT
></A
>, 
filled with the audio data format of the wave data, and sets 
<TT
CLASS="PARAMETER"
><I
>audio_buf</I
></TT
> to a <TT
CLASS="FUNCTION"
>malloc</TT
>'d 
buffer containing the audio data, and sets <TT
CLASS="PARAMETER"
><I
>audio_len</I
></TT
> 
to the length of that audio buffer, in bytes.  You need to free the audio 
buffer with <A
HREF="sdlfreewav.html"
><TT
CLASS="FUNCTION"
>SDL_FreeWAV</TT
></A
> when you are
done with it.</P
><P
>This function returns <TT
CLASS="LITERAL"
>NULL</TT
> and sets the SDL 
error message if the wave file cannot be opened, uses an unknown data format, 
or is corrupt.  Currently raw, MS-ADPCM and IMA-ADPCM WAVE files are supported.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6841"
></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>SDL_AudioSpec wav_spec;
Uint32 wav_length;
Uint8 *wav_buffer;

/* Load the WAV */
if( SDL_LoadWAV("test.wav", &#38;wav_spec, &#38;wav_buffer, &#38;wav_length) == NULL ){
  fprintf(stderr, "Could not open test.wav: %s\n", SDL_GetError());
  exit(-1);
}
.
.
.
/* Do stuff with the WAV */
.
.
/* Free It */
SDL_FreeWAV(wav_buffer);</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6844"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlaudiospec.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
></A
>,
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
>,
<A
HREF="sdlfreewav.html"
><TT
CLASS="FUNCTION"
>SDL_FreeWAV</TT
></A
></P
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