Re: cheese-3.10.2 does not detect webcam but guvcview does

[Bastien Nocera <hadess hadess net>]

On Mon, 2014-05-26 at 12:00 +0000, John Frankish wrote:
> > -----Original Message-----
> > From: Bastien Nocera [mailto:hadess hadess net]
> > Sent: Monday, 26 May, 2014 14:15
> > To: John Frankish
> > Cc: cheese-list gnome org
> > Subject: Re: cheese-3.10.2 does not detect webcam but guvcview does
> >
> > On Sat, 2014-05-24 at 15:07 +0000, John Frankish wrote:
> > > #6  0x000000000040f0d3 in cheese_effects_manager_add_effect
> > > (effect=<optimized out>, name=<optimized out>, self=0x1ed5610)
> > >     at src/cheese-effects-manager.c:222
> >
> > Still missing important debug information I'm afraid.
> 'seems the trick is to compile with "-ggdb"
>
> $ G_DEBUG=fatal_warnings gdb --args cheese --device=/dev/video0
> GNU gdb (GDB) 7.5.1
> ...
> Reading symbols from /usr/local/bin/cheese...done.
> (gdb) run
> Starting program: /usr/local/bin/cheese --device=/dev/video0
> ...
> (cheese:11206): GStreamer-CRITICAL **: gst_bin_add: assertion 'GST_IS_ELEMENT (element)' failed
>
> Program received signal SIGTRAP, Trace/breakpoint trap.
> 0x00007fffecf1700e in g_logv () from /usr/local/lib/libglib-2.0.so.0
> (gdb) bt
> #0  0x00007fffecf1700e in g_logv () from /usr/local/lib/libglib-2.0.so.0
> #1  0x00007fffecf1717f in g_log () from /usr/local/lib/libglib-2.0.so.0
> #2  0x00007ffff659e191 in gst_bin_add () from /usr/local/lib/libgstreamer-1.0.so.0
> #3  0x00007ffff65b06ec in priv_gst_parse_yyparse () from /usr/local/lib/libgstreamer-1.0.so.0
> #4  0x00007ffff6575f16 in gst_parse_launch_full () from /usr/local/lib/libgstreamer-1.0.so.0
> #5  0x00007ffff65ae7ec in gst_parse_bin_from_description_full () from /usr/local/lib/libgstreamer-1.0.so.0
> #6  0x0000000000423839 in cheese_effects_manager_add_effect (self=0x1e80840, name=0x1e6abd0 "Time delay", 
> effect=0x1e6a720)
>     at src/cheese-effects-manager.c:222

It's trying to build the Time delay effect which needs the
"frei0r-filter-delay0r" plugin (which lives in the gst-plugins-bad
package). Cheese should probably do better at avoiding crashing when an
effect isn't available.

Could you please re-test with cheese 3.12.x, and file a bug if the
problem persists?

Cheers