Re: Using Wx::MediaCtrl to display a live videofeed (eg a webcam)

[Anonymous Monk]

Do you have a wxLogWindow? Some kind of error message should be reported... Can you run it with strace?

[Steve_BZ]

Hi Anon,

Thanks for this. I didn't have LogWindow installed, so I just did that and I get:

21:56:14: Error: gst_error_callback
Error Message:Invalid URI "/dev/video0".
Debug:gstplaybasebin.c(1666): gen_source_element (): /GstPlayBin:play
 (error 0: Success)
21:56:14: Error: wxGStreamerMediaBackend::Load - Could not set initial
+ state to ready (error 0: Success)

I guess it doesn't like the /dev/video0. Maybe it really expects a URL, but assuming it means a URI, then should I just put my computer name in front of it like this? steve-desktop/dev/video0 because that doesn't work either.

Do you know what format is correct?

Thanks and regards

Steve.

PS I tried the strace, but it gave me pages and pages of info. I'll have a go at filtering it down, and post it here.

[Anonymous Monk]

$ perl -MURI::file -le"die URI::file->new( shift )->canonical " /dev/v
+ideo0
file:///dev/video0

[Steve_BZ]

Hi Monks,

Well, I've now rebuilt the hardware and everything is cookin' nicely.

I tried $i_frame->{Ctl_Videos_Media}->LoadURI ('file:///dev/video0'); and I no longer get any errors in LogWindow but no picture in the media control.

Update: Oookaaay, now my hardware is compliant with that age-old standard of plugging the webcam in, we have some progress! The progress bar on the application flickers (although not the image) and print $i_frame->{Ctl_Videos_Media}->LoadURI ('file:///dev/video0'); returns "1" but gives error Gtk-CRITICAL **: gtk_range_set_range: assertion `min < max' failed, so I guess it is accessing the URI, but maybe it is immediately hitting EOF, or something.

Update 2: According to Similar wxPython problem it may be missing GStreamer packages. This sounds like a possibility, so I'm going to try to track this down. If you know what the correct list is, please share :)

Regards

Steve.