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annotate src/audio/SDL_audio_c.h @ 2042:3908e1f808e1

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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 15:56:36 +0000
parents 3b4ce57c6215
children 344c8da164f4 99210400e8b9
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1 /*
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2 SDL - Simple DirectMedia Layer
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3 Copyright (C) 1997-2006 Sam Lantinga
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5 This library is free software; you can redistribute it and/or
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6 modify it under the terms of the GNU Lesser General Public
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7 License as published by the Free Software Foundation; either
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8 version 2.1 of the License, or (at your option) any later version.
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9
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10 This library is distributed in the hope that it will be useful,
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11 but WITHOUT ANY WARRANTY; without even the implied warranty of
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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13 Lesser General Public License for more details.
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14
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15 You should have received a copy of the GNU Lesser General Public
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16 License along with this library; if not, write to the Free Software
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17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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19 Sam Lantinga
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20 slouken@libsdl.org
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21 */
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22 #include "SDL_config.h"
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23
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24 /* Functions and variables exported from SDL_audio.c for SDL_sysaudio.c */
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25
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26 /* Functions to get a list of "close" audio formats */
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27 extern SDL_AudioFormat SDL_FirstAudioFormat(SDL_AudioFormat format);
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28 extern SDL_AudioFormat SDL_NextAudioFormat(void);
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29
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30 /* Function to calculate the size and silence for a SDL_AudioSpec */
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31 extern void SDL_CalculateAudioSpec(SDL_AudioSpec * spec);
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33 /* The actual mixing thread function */
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34 extern int SDLCALL SDL_RunAudio(void *audiop);
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35
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36 /* this is used internally to access some autogenerated code. */
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37 typedef struct
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38 {
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39 SDL_AudioFormat src_fmt;
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40 SDL_AudioFormat dst_fmt;
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41 SDL_AudioFilter filter;
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42 } SDL_AudioTypeFilters;
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43 extern const SDL_AudioTypeFilters sdl_audio_type_filters[];
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44
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45 /* vi: set ts=4 sw=4 expandtab: */