Seen with
Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4996977/bin/ncomms12571-s3.avi via https://commons.wikimedia.org/wiki/File:El-Ni%C3%B1o-and-coral-larval-dispersal-across-the-eastern-Pacific-marine-barrier-ncomms12571-s3.webm
Example failing: https://test.wikipedia.org/wiki/File:Transcode-testing-from-avi.webm
Example workaround with higher frame rate: https://test.wikipedia.org/wiki/File:Transcode-testing-from-avi-30fps.webm
Creating the webm that fails:
ffmpeg -i ncomms12571-s3.avi -c:v libvpx -c:a libvorbis transcode-testing-from-avi.webm
that works:
ffmpeg -i ncomms12571-s3.avi -c:v libvpx -c:a libvorbis -r 30 transcode-testing-from-avi-30fps.webm
The command line for a transcode that fails in vagrant:
ffmpeg -y -i transcode-testing-from-avi.webm -threads 1 -skip_threshold 0 -bufsize 6000k -rc_init_occupancy 4000 -qmin 1 -qmax 51 -vb 512000 -vcodec libvpx -g 128 -keyint_min 128 -f webm -s 476x360 -an -pass 1 -passlogfile temp.log /dev/null
Error:
[libvpx @ 0xe7f780] Failed to initialize encoder: Invalid parameter [libvpx @ 0xe7f780] Additional information: g_timebase.num out of range [1..cfg->g_timebase.den
No error found running same command with ffmpeg 3.1.5 on my mac.