Mercurial > sdl-ios-xcode

annotate src/audio/dummy/SDL_dummyaudio.c @ 2661:d38309be5178 gsoc2008_audio_resampling

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The windowed sinc filter generation code seems to be working fine. The FIR filtering code is also now working reasonably well. Occasionally the FIR filter will pop, but setting the normalization factor lower seems to help this. I suspect the problem is in the fixed point multiply/add. I also have a hunch the zero stuffing/sample discarding code is not correct, and I'll look at that soon to get it sorted out.
author Aaron Wishnick <schnarf@gmail.com>
date Wed, 02 Jul 2008 08:04:50 +0000
parents 866052b01ee5
children 99210400e8b9
rev   line source
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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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4
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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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18
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19 Sam Lantinga
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20 slouken@libsdl.org
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21
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60620d71e324 Corrected dummy audio callback firing to be realistic, cleaned up tabs.
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22 This file written by Ryan C. Gordon (icculus@icculus.org)
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23 */
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24 #include "SDL_config.h"
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25
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38c1eb6b0083 By default all the real targets have dummy audio/video and disk audio.
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26 /* Output audio to nowhere... */
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27
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28 #include "SDL_audio.h"
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29 #include "../SDL_audio_c.h"
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30 #include "SDL_dummyaudio.h"
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31
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32 static int
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33 DUMMYAUD_OpenDevice(_THIS, const char *devname, int iscapture)
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34 {
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35 return 1; /* always succeeds. */
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36 }
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38 static int
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39 DUMMYAUD_Init(SDL_AudioDriverImpl * impl)
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40 {
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41 /* Set the function pointers */
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42 impl->OpenDevice = DUMMYAUD_OpenDevice;
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43 impl->OnlyHasDefaultOutputDevice = 1;
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44 return 1;
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45 }
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46
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47 AudioBootStrap DUMMYAUD_bootstrap = {
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48 "dummy", "SDL dummy audio driver", DUMMYAUD_Init, 1
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49 };
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50
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51 /* vi: set ts=4 sw=4 expandtab: */