d884af2b99
imdct and windowing are all in fixed point. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@27302 a1c6a512-1295-4272-9138-f99709370657
40 lines
1.3 KiB
Text
40 lines
1.3 KiB
Text
Library: libwmapro
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Imported: 2010-04-30 by Mohamed Tarek
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This set of files form the files needed from ffmpeg's libavcodec and libavutil
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to build a standalone wma professional decoder.
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LICENSING INFORMATION
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ffmpeg is licensed under the Lesser GNU General Public License and the file
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wmaprodec.c is copyright (c) 2007 Baptiste Coudurier, Benjamin Larsson, Ulion
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and copyright (c) 2008 - 2009 Sascha Sommer, Benjamin Larsson.
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IMPORT DETAILS
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Based on ffmpeg svn r22886 dated 15 April 2010.
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The code is slowly being modified to convert it from floating point maths to
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fixed point.
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As of 6 July 2010, the following steps are all working properly in fixed point:
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- Inverse quantization and rescaling
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- IMDCT
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- Windowing
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Results of comparing output wav files from the partially fixed point decoder to
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the output wav files of ffmpeg decoder are :
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- average relative error = 0.016%
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- maximum relative error = 0.3%
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COMPILING
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At the time of this writing (21 June 2010) the decoder isn't still included in
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the main build since it still only works in the simulator.
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A patch is included that would enable building the library and the codec for
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testing and development purposes.
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To apply the patch, you should cd to libwmapro directory and then execute the
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following command :
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patch -p 0 < wmapro_mainbuild.patch
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