[MPlayer-dev-eng] [PATCH] Fixed-point WMA decoder adapted from ROckbox

compn tempn at twmi.rr.com
Tue Apr 29 20:14:27 CEST 2008


On Tue, 29 Apr 2008 11:49:09 -0500
Matt Campbell <mattcampbell at pobox.com> wrote:

> I'm sorry, I didn't mean to remove the libdca check in configure; I was 
> merely using the libdca check as a template for what I needed to add for 
> libwma.  Here's a corrected patch.
> 
> As for patching libavcodec, the problem is that libwma includes modified 
> versions of the FFT and MDCT functions from libavcodec, since the WMA 
> decoder requires the MDCT function.  So if I patch libavcodec, then I'll 
> also have to fix all of the other codecs in libavcodec that use MDCT 
> and/or FFT, to use fixed-point numbers for these functions instead of 
> floats.  And I'm not sure what else was changed in libwma relative to 
> libavcodec; as I said before, I took libwma from Rockbox.

well you wont have to fix all of the other codecs, the ffmpeg team will.
but i see now what you mean, you swiped it from rockbox, and have nothing to do with rockbox or ffmpeg.

sorry for the confusion

-compn


> 
> Matt
> 
> compn wrote:
> > On Tue, 29 Apr 2008 10:48:25 -0500
> > Matt Campbell <mattcampbell at pobox.com> wrote:
> > 
> >> Hello:
> >>
> >> Attached is a patch for MPlayer which adds a fixed-point WMA decoder 
> >> that I adapted from Rockbox.  Rockbox's fixed-point WMA decoder was in 
> >> turn adapted from the one in libavcodec, so it would seem that the best 
> >> approach is to port the modifications from the Rockbox WMA decoder back 
> >> to libavcodec.  But I didn't want to break libavcodec.  So instead, I 
> >> turned the libwma library from ROckbox into a stand-alone library which 
> >> can run outside of Rockbox, then added it to the MPlayer build system 
> >> and wrote an audio decoder plug-in for libwma (based on ad_ffmpeg.c). 
> >> The attached patch also includes some changes to etc/codecs.conf.
> > 
> > this would be better off in libavcodec. if you can, submit a diff of svn libavcodec to ffmpeg-devel. at least it will be a starting point. i'll add it to the ffmpeg small projects wiki.
> > 
> > as for your patch, it seems to remove the check for libdca for some reason.
> > 
> > -echocheck "libdca support"
> > -if test "$_libdca" = auto ; then
> > -  _libdca=no
> > -  cat > $TMPC << EOF
> > -#include <inttypes.h>
> > -#include <dts.h>
> > -int main(void) { dts_init (0); return 0; }
> > -EOF
> > -  cc_check -ldts $_ld_lm && _libdca=yes
> > -fi
> > -if test "$_libdca" = yes ; then
> > -  _def_libdca='#define USE_LIBDCA 1'
> > -  _ld_extra="$_ld_extra -ldts"
> > -  _codecmodules="libdca $_codecmodules"
> > 
> > 
> > -compn
> > _______________________________________________
> > MPlayer-dev-eng mailing list
> > MPlayer-dev-eng at mplayerhq.hu
> > https://lists.mplayerhq.hu/mailman/listinfo/mplayer-dev-eng
> > 
> 



More information about the MPlayer-dev-eng mailing list