view docs/html/sdldisplayyuvoverlay.html @ 3880:74e828c64315 SDL-1.2

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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><H1
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>SDL_DisplayYUVOverlay</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2908"
></A
><H2
>Name</H2
>SDL_DisplayYUVOverlay&nbsp;--&nbsp;Blit the overlay to the display</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN2911"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN2912"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_DisplayYUVOverlay</B
></CODE
>(SDL_Overlay *overlay, SDL_Rect *dstrect);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2918"
></A
><H2
>Description</H2
><P
>Blit the <TT
CLASS="PARAMETER"
><I
>overlay</I
></TT
> to the surface specified when it was <A
HREF="sdlcreateyuvoverlay.html"
>created</A
>. The <A
HREF="sdlrect.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Rect</SPAN
></A
> structure, <TT
CLASS="PARAMETER"
><I
>dstrect</I
></TT
>, specifies the position and size of the destination. If the <TT
CLASS="PARAMETER"
><I
>dstrect</I
></TT
> is a larger or smaller than the overlay then the overlay will be scaled, this is optimized for 2x scaling.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2927"
></A
><H2
>Return Values</H2
><P
>Returns 0 on success</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2930"
></A
><H2
>See Also</H2
><P
><A
HREF="sdloverlay.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Overlay</SPAN
></A
>,
<A
HREF="sdlcreateyuvoverlay.html"
><TT
CLASS="FUNCTION"
>SDL_CreateYUVOverlay</TT
></A
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