[Pkg-telepathy-maintainers] Bug#687798: Webcam with inbuilt compression (Logitech B990) works intermittently

[Daniel Pocock]

Package: empathy
Version: 3.4.2.3-1

On squeeze, with the older version of empathy, this webcam causes
empathy to become frozen (as described in bug 687789):
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=687789

On wheezy, no freezes, but the webcam only works intermittently

When it does not work, the local video source (in the bottom left hand
corner of the window) appears white, and the remote party sees all black
background

Simply switching the local source off and on a few times eventually
makes it work

This webcam is unusual in that it has inbuilt H.264 streaming support.
Nonetheless, applications that don't support that feature should still
work by using it as a normal UVC webcam.  A related bug observed with
guvcview may give hints about this:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=687440

Also, in at least one instance, calling from 3.4.2.3-1 (wheezy) to
empathy on squeeze, it is observed that the squeeze instance of empathy
is logging messages like the following on stdout:

[h263 @ 0x1de8c00] Error, Invalid timestamp=4060, last=4060

continuously, although this can even be seen when it is working.