gistfile1.txt

x220:/tmp/r$ ffmpeg -strict 2 -i raw.mkv -acodec copy -vcodec libvpx encode.webm                                                                                          
ffmpeg version 1.0 Copyright (c) 2000-2012 the FFmpeg developers                                                                                                          
  built on Sep 29 2012 11:22:50 with gcc 4.7.1 (GCC) 20120721 (prerelease)                                                                                                
  configuration: --prefix=/usr --enable-libmp3lame --enable-libvorbis --enable-libxvid --enable-libx264 --enable-libvpx --enable-libtheora --enable-libgsm --enable-libspe
ex --enable-postproc --enable-shared --enable-x11grab --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libschroedinger --enable-libopenjpeg --enable-librtmp
 --enable-libpulse --enable-libv4l2 --enable-gpl --enable-version3 --enable-runtime-cpudetect --disable-debug --disable-static                                            
  libavutil      51. 73.101 / 51. 73.101                                                                                                                                  
  libavcodec     54. 59.100 / 54. 59.100                                                                                                                                  
  libavformat    54. 29.104 / 54. 29.104                                                                                                                                  
  libavdevice    54.  2.101 / 54.  2.101                                                                                                                                  
  libavfilter     3. 17.100 /  3. 17.100                                                                                                                                  
  libswscale      2.  1.101 /  2.  1.101                                                                                                                                  
  libswresample   0. 15.100 /  0. 15.100                                                                                                                                  
  libpostproc    52.  0.100 / 52.  0.100                                                                                                                                  
Guessed Channel Layout for  Input Stream #0.1 : stereo                                                                                                                    
Input #0, matroska,webm, from 'raw.mkv':                                                                                                                                  
  Metadata:                                                                                                                                                               
    ENCODER         : Lavf54.29.104                                                                                                                                       
  Duration: 00:00:05.00, start: 0.000000, bitrate: 291553 kb/s                                                                                                            
    Stream #0:0: Video: ffvhuff (FFVH / 0x48564646), bgra, 1366x768, SAR 1:1 DAR 683:384, 30 fps, 30 tbr, 1k tbn, 1k tbc (default)                                        
    Stream #0:1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s (default)                                                                                             
File 'encode.webm' already exists. Overwrite ? [y/N] y                                                                                                                    
v1.1.0                                                                                                                                                                    
[webm @ 0x1c2a6e0] Only VP8 video and Vorbis audio are supported for WebM.                                                                                                
Output #0, webm, to 'encode.webm':                                                                                                                                        
  Metadata:                                                                                                                                                               
    encoder         : Lavf54.29.104                                                                                                                                       
    Stream #0:0: Video: vp8, yuv420p, 1366x768 [SAR 1:1 DAR 683:384], q=-1--1, 200 kb/s, 1k tbn, 30 tbc (default)                                                         
    Stream #0:1: Audio: pcm_s16le, 48000 Hz, stereo, 1536 kb/s (default)                                                                                                  
Stream mapping:                                                                                                                                                           
  Stream #0:0 -> #0:0 (ffvhuff -> libvpx)                                                                                                                                 
  Stream #0:1 -> #0:1 (copy)                                                                                                                                              
Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument