I have been investigating the ways and means of the 'routing' of FFMPEG internally. I've built from source binaries with Windows and C99to89.
I build with --enable-libvpx. I was keenly interested in the ability of libvpx to create/encode "webm" with alpha. ( output from ffprobe ffprobe version 2.3.git Copyright (c) 2007-2014 the FFmpeg developers built on Aug 21 2014 09:14:40 with Microsoft (R) 32-bit C/C++ Optimizing Compi ler Version 16.00.40219.01 for 80x86 configuration: --toolchain=msvc --enable-shared --enable-libvpx --enable-libvo rbis --disable-pthreads libavutil 54. 5.100 / 54. 5.100 libavcodec 56. 0.101 / 56. 0.101 libavformat 56. 1.100 / 56. 1.100 libavdevice 56. 0.100 / 56. 0.100 libavfilter 5. 0.100 / 5. 0.100 libswscale 3. 0.100 / 3. 0.100 libswresample 1. 1.100 / 1. 1.100 ) Hey, it built and it 'seemed' to work. So I started digging in and then discovered that it doesn't decode alpha yet. HA, that was a surprise. So I started examining the "FFmpeg codec HOWTO" (http://wiki.multimedia.cx/index.php?title=FFmpeg_codec_HOWTO) and instrumented some printf instructions into libvpxdec.c in vpx_init() and vp8_decode(). These don't ever appear, so I also tried to do a fopen("abc.txt") and that doesn't get created. So WHAT routes the linkage to Where? So I dumped --codecs and low and behold DEV.L. vp8 On2 VP8 (decoders: vp8 libvpx ) (encoders: libvpx ) DEV.L. vp9 Google VP9 (decoders: vp9 libvpx-vp9 ) (encoders: libvpx-vp9 ) There's 2 DECODERS for vp8 and vp8 and the 'internal' one is used first ! Isn't that a build bug? Do I need to do a --disable-vp8, etc? _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel