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Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents 355632dca928
children
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<HTML
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>SDL_Init</TITLE
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>SDL_Init</H1
><DIV
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><A
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><H2
>Name</H2
>SDL_Init&nbsp;--&nbsp;Initializes SDL</DIV
><DIV
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><H2
>Synopsis</H2
><DIV
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_Init</B
></CODE
>(Uint32 flags);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
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></A
><H2
>Description</H2
><P
>Initializes SDL. This should be called before all other SDL functions. The <TT
CLASS="PARAMETER"
><I
>flags</I
></TT
> parameter specifies what part(s) of SDL to initialize.</P
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><TD
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><TT
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><TD
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>Initializes the <A
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><TT
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>SDL_INIT_AUDIO</TT
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><TD
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>Initializes the <A
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> subsystem.</TD
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><TT
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>SDL_INIT_VIDEO</TT
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>Initializes the <A
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> subsystem.</TD
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><TT
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>SDL_INIT_CDROM</TT
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>Initialize all of the above.</TD
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>Prevents SDL from catching fatal signals.</TD
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><TT
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>SDL_INIT_EVENTTHREAD</TT
></TD
><TD
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>&nbsp;</TD
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><P
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></DIV
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><H2
>Return Value</H2
><P
>Returns <SPAN
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>-1</SPAN
> on an error or <SPAN
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>0</SPAN
> on success.</P
></DIV
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><A
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><H2
>See Also</H2
><P
><A
HREF="sdlquit.html"
><TT
CLASS="FUNCTION"
>SDL_Quit</TT
></A
>,
<A
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><TT
CLASS="FUNCTION"
>SDL_InitSubSystem</TT
></A
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