Thumbnailing videos taken by camera is very slow (over 5 seconds on BQ)

[Florian Boucault]

Steps:

1. Shoot a 1080p video with the camera
2. Go to the camera roll of the camera and wait for the video thumbnail to show up

It takes a long time before the thumbnail is finished generating.

[Florian Boucault (fboucault)]

Something like 1 second out of the 5+ seconds it takes on BQ is due to https://bugs.launchpad.net/thumbnailer/+bug/1425009

[Michi Henning (michihenning)]

With the new thumbnailer, I don't think that's still an issue. On my Nexus 4, I see the thumbnail in less than a second.

[Michi Henning (michihenning)]

I spoke too soon, it's still slow. However, not because of anything in thumbnailer, but because gstreamer takes a long time to extract a thumbnail.

The code we use to extract thumbnails is in lp:thumbnailer, in the src/vs-thumb directory. It's only a few dozen lines long.

[Michi Henning (michihenning)]

Due to instability in gstreamer, we are currently limiting the number of concurrent vs-thumb processes. On __arm__, if max-extractions = 0 (which is the default), we adjust max-extractions to 1, so only one vs-thumb process executes at a time.

It's still possible to force more than one concurrent vs-thumb by setting max-extractions to a non-zero value (useful for testing). For example:

gsettings set com.canonical.Unity.Thumbnailer max-extractions 2

[Michi Henning (michihenning)]

Changing to "triaged" for thumbnailer because we are the meat in the sandwich.

[Michi Henning (michihenning)]

It doesn't look like anything will ever be done to fix this, so I'm closing this for thumbnailer.