Gray thumbnails generated for some videos

[Timo Jyrinki]

The Shotwell thumbnailer is limited in the way it does seeking in some video formats, resulting in data that is not the full video frame but only interframe data, resulting in mostly gray thumbnails for such video formats. This is not a GStreamer bug, since Totem thumbnailer works fine, so it's a difference in how GStreamer is used.

This can be tested manually with:
/usr/lib/shotwell/shotwell-video-thumbnailer video.MTS > out.png

Sony AVCHD format (MTS) is one example, while the MP4 from Sony's better XAVC S format works fine.

This Ubuntu bug is for following the upstream bug report.

[Test Case]

wget http://kernelcat.com/shotwell/20141230125000.MTS
totem-video-thumbnailer -r 20141230125000.MTS totem.png
/usr/lib/shotwell/shotwell-video-thumbnailer 20141230125000.MTS > shotwell.png
ffmpegthumbnailer -s0 -i20141230125000.MTS -offmpeg.png

Totem and ffmpegthumbnailer generate a correct thumbnail, Shotwell does not.

[Timo Jyrinki (timo-jyrinki)]

For Ubuntu 14.04 LTS users I've personally used a solution that uses totem or ffmpegthumbnailer instead, available via https://launchpad.net/~timo-jyrinki/+archive/ubuntu/shotwell:

sudo apt-add-repository ppa:timo-jyrinki/shotwell
sudo apt update
sudo apt upgrade
sudo apt install ffmpegthumbnailer

The current patch uses ffmpegthumbnailer because of a GStreamer bug that did get fixed already in May 2014 but I just didn't switch back to the Totem thumbnailer.