title: Conversion for WebM file format using FFMPEG
body: <p>I am using followng command to convert video to webm format</p>
  
  <pre class="lang-none prettyprint-override"><code>ffmpeg -i video/ds2.mp4 -acodec libvorbis -ac 2 -ab 96k -ar 44100 -b:a 345k -s 640x360 video/ds2.webm
  </code></pre>
  
  <p>I am receiving following errors:</p>
  
  <p>1) incompatible sample format 's16' for codec 'libvorbis' </p>
  
  <p>2) strptime() unavailable on this system, cannot convert the data string</p>
  
  <p>Do you any idea why I cannot convert, tested conversion to FLV and it's working very well</p>
  
  <p>Console output</p>
  
  <pre class="lang-none prettyprint-override"><code>C:\inetpub\wwwroot&gt;ffmpeg -i video/testavi.avi video/ds2.webm
  ffmpeg version N-35709-g7d531e8, Copyright (c) 2000-2011 the FFmpeg developers
    built on Dec 12 2011 13:56:52 with gcc 4.6.2
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
  ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
  ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
  able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
  -enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
  c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
  libxvid --enable-zlib
    libavutil    51. 32. 0 / 51. 32. 0
    libavcodec   53. 43. 0 / 53. 43. 0
    libavformat  53. 24. 0 / 53. 24. 0
    libavdevice  53.  4. 0 / 53.  4. 0
    libavfilter   2. 53. 0 /  2. 53. 0
    libswscale    2.  1. 0 /  2.  1. 0
    libpostproc  51.  2. 0 / 51.  2. 0
  Input #0, avi, from 'video/testavi.avi':
    Metadata:
      encoder         : Lavf51.12.1
    Duration: 00:00:13.03, start: 0.000000, bitrate: 36427 kb/s
      Stream #0:0: Video: msmpeg4 (MP43 / 0x3334504D), yuv420p, 1920x1080, 30 tbr,
   30 tbn, 30 tbc
      Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16, 192 kb
  /s
  File 'video/ds2.webm' already exists. Overwrite ? [y/N] y
  w:1920 h:1080 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
  [libvpx @ 0000000001CA9BB0] v0.9.7-p1
  Output #0, webm, to 'video/ds2.webm':
    Metadata:
      encoder         : Lavf53.24.0
      Stream #0:0: Video: vp8, yuv420p, 1920x1080, q=-1--1, 200 kb/s, 1k tbn, 30 t
  bc
      Stream #0:1: Audio: vorbis, 44100 Hz, stereo, s16, 128 kb/s
  Stream mapping:
    Stream #0:0 -&gt; #0:0 (msmpeg4 -&gt; libvpx)
    Stream #0:1 -&gt; #0:1 (mp3 -&gt; libvorbis)
  Press [q] to stop, [?] for help
  </code></pre>
  
  <hr>
  
  <pre><code>Problem signature:
    Problem Event Name:   APPCRASH
    Application Name: ffmpeg.exe
    Application Version:  0.0.0.0
    Application Timestamp:    4ee64f02
    Fault Module Name:    ffmpeg.exe
    Fault Module Version: 0.0.0.0
    Fault Module Timestamp:   4ee64f02
    Exception Code:   c0000005
    Exception Offset: 000000000091e090
    OS Version:   6.1.7601.2.1.0.272.7
    Locale ID:    1033
    Additional Information 1: ab8f
    Additional Information 2: ab8f35a907f8f11a8d2e787a8e40efbd
    Additional Information 3: f4d5
    Additional Information 4: f4d524f8bf76a4b71cc6a7afa6412ca9
  
  Read our privacy statement online:
    http://go.microsoft.com/fwlink/?linkid=104288&amp;clcid=0x0409
  
  If the online privacy statement is not available, please read our privacy statement offline:
    C:\Windows\system32\en-US\erofflps.txt
  </code></pre>
  
  <p>And Console Uncut Output</p>
  
  <pre><code>C:\inetpub\wwwroot&gt;ffmpeg.exe -i "video/testavi.avi" -acodec libvorbis -b:a 96k
  -ac 2 -vcodec libvpx -b:v 400k -f webm -s 384x216 "video/testavi.webm"
  ffmpeg version N-35709-g7d531e8, Copyright (c) 2000-2011 the FFmpeg developers
    built on Dec 12 2011 13:56:52 with gcc 4.6.2
    configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
  ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
  ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
  able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
  -enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
  c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
  libxvid --enable-zlib
    libavutil    51. 32. 0 / 51. 32. 0
    libavcodec   53. 43. 0 / 53. 43. 0
    libavformat  53. 24. 0 / 53. 24. 0
    libavdevice  53.  4. 0 / 53.  4. 0
    libavfilter   2. 53. 0 /  2. 53. 0
    libswscale    2.  1. 0 /  2.  1. 0
    libpostproc  51.  2. 0 / 51.  2. 0
  Input #0, avi, from 'video/testavi.avi':
    Metadata:
      encoder         : Lavf51.12.1
    Duration: 00:00:13.03, start: 0.000000, bitrate: 36427 kb/s
      Stream #0:0: Video: msmpeg4 (MP43 / 0x3334504D), yuv420p, 1920x1080, 30 tbr,
   30 tbn, 30 tbc
      Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16, 192 kb
  /s
  [buffer @ 0000000001D7FF60] w:1920 h:1080 pixfmt:yuv420p tb:1/1000000 sar:0/1 sw
  s_param:
  [scale @ 0000000001D7E9E0] w:1920 h:1080 fmt:yuv420p -&gt; w:384 h:216 fmt:yuv420p
  flags:0x4
  [libvpx @ 0000000001BF7C10] v0.9.7-p1
  Output #0, webm, to 'video/testavi.webm':
    Metadata:
      encoder         : Lavf53.24.0
      Stream #0:0: Video: vp8, yuv420p, 384x216, q=-1--1, 400 kb/s, 1k tbn, 30 tbc
  
      Stream #0:1: Audio: vorbis, 44100 Hz, 2 channels, s16, 96 kb/s
  Stream mapping:
    Stream #0:0 -&gt; #0:0 (msmpeg4 -&gt; libvpx)
    Stream #0:1 -&gt; #0:1 (mp3 -&gt; libvorbis)
  Press [q] to stop, [?] for help
  </code></pre>