gistfile1.txt

$ sudo ffmpeg -sameq -i test.flv test.webm
ffmpeg version 0.7.8-rpmfusion, Copyright (c) 2000-2011 the FFmpeg developers
  built on Dec 22 2011 03:32:58 with gcc 4.6.1 20110908 (Red Hat 4.6.1-9)
  configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib --mandir=/usr/share/man --arch=i686 --extra-cflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m32 -march=i686 -mtune=atom -fasynchronous-unwind-tables' --extra-version=rpmfusion --enable-bzlib --enable-libcelt --enable-libdc1394 --enable-libdirac --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-x11grab --enable-avfilter --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib --cpu=i686 --enable-runtime-cpudetect
  libavutil    50. 43. 0 / 50. 43. 0
  libavcodec   52.123. 0 / 52.123. 0
  libavformat  52.111. 0 / 52.111. 0
  libavdevice  52.  5. 0 / 52.  5. 0
  libavfilter   1. 80. 0 /  1. 80. 0
  libswscale    0. 14. 1 /  0. 14. 1
  libpostproc  51.  2. 0 / 51.  2. 0
[flv @ 0x8810280] Estimating duration from bitrate, this may be inaccurate

Seems stream 0 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 25.00 (25/1)
Input #0, flv, from 'test.flv':
  Metadata:
    duration        : 49
    width           : 1280
    height          : 720
    videodatarate   : 195
    framerate       : 25
    videocodecid    : 2
    audiodatarate   : 62
    audiosamplerate : 11025
    audiosamplesize : 16
    stereo          : false
    audiocodecid    : 1
    filesize        : 45376179
  Duration: 00:00:48.94, start: 0.000000, bitrate: 264 kb/s
    Stream #0.0: Video: flv, yuv420p, 1280x720, 200 kb/s, 25 tbr, 1k tbn, 1k tbc
    Stream #0.1: Audio: adpcm_swf, 11025 Hz, 1 channels, s16, 64 kb/s
[buffer @ 0x88bb5a0] w:1280 h:720 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[libvpx @ 0x8812440] v0.9.7-p1
[libvorbis @ 0x8818300] oggvorbis_encode_init: init_encoder failed
Output #0, webm, to 'test.webm':
    Stream #0.0: Video: libvpx, yuv420p, 1280x720, q=2-31, 200 kb/s, 90k tbn, 25 tbc
    Stream #0.1: Audio: libvorbis, 11025 Hz, 1 channels, s16, 64 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
Error while opening encoder for output stream #0.1 - maybe incorrect parameters such as bit_rate, rate, width or height