view docs/html/sdlloadwav.html @ 1260:80f8c94b5199

Date: 10 Jun 2003 15:30:59 -0400 From: Mike Shal Subject: [SDL] Bug in SDL_wave.c? Hey everyone, I'm not sure if this is a bug in SDL, or if I just have incorrect WAV files. The problem I'm having is loading multiple concatenated WAVs from SDL_LoadWAV_RW. Some WAV files put comments at the end of the file (which may be bad form), and SDL doesn't skip past them when reading from the RWops. So the next WAV I try to load will start at the comment section of the previous WAV, which obviously doesn't work. If anyone else is having this problem, one quick fix you can do is run sox on the bad WAVs, which strips out all of the comment sections. Eg: $ sox sound.wav tmp.wav $ mv -f tmp.wav sound.wav The other fix is to patch SDL_wave.c, which is included with this email. (Assuming I made the patch correctly :). All it does is calculate how much remaining space there is in the WAV file after the data chunk, and does SDL_RWseek to skip it. I don't think it should interfere with anything else, but if someone could check it that would be nice :). If the bug is really with SDL and not with my WAVs, can someone work this into the next version of SDL? Thanks, -Mike Shal
author Sam Lantinga <slouken@libsdl.org>
date Tue, 24 Jan 2006 07:20:18 +0000
parents 355632dca928
children
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><H1
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>SDL_LoadWAV</H1
><DIV
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><A
NAME="AEN6816"
></A
><H2
>Name</H2
>SDL_LoadWAV&nbsp;--&nbsp;Load a WAVE file</DIV
><DIV
CLASS="REFSYNOPSISDIV"
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><H2
>Synopsis</H2
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><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
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><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
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><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
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CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
></A
>,
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
>,
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HREF="sdlfreewav.html"
><TT
CLASS="FUNCTION"
>SDL_FreeWAV</TT
></A
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