GNOME Bugzilla – Bug 150577
[sdlvideosink] gives very bad picture (as if untuned or in wrong color format or so)
Last modified: 2005-11-11 16:09:30 UTC
I used scantv to get the frequencies in MHz of two Swedish TV channels. Using the pipeline "gst-launch-0.8 v4l2src device=/dev/video0 frequency=182250000 ! video/x-raw-rgb, bpp=24, width=704, height=576 ! spider ! sdlvideosink" I can view both (by multiplying the frequency with 1000000), but get very crappy picture. Both channels work in xawtv, tvtime, zapping etc.
Created attachment 30763 [details] Screen shot of result of pipeline
Also, why are v4lsrc and v4l2src so different?
Because v4l and v4l2 are not the same. Size negotiation is done completely different in the two.
I just tried changing sdlvideosink to ximagesink, and got a perfect picture, so this bug is almost certainly in sdlvideosink. Further testing, with an mpeg file as source, also gives similar distortion, but then I was unable to test with ximagesink due to a (capability?) negotiation error. I've filed that as bug 150670.
Niklas, there have been multiple updates to the SDL sink since you filed this, but I don't have anything to reproduce your bug with. Could you please retry with latest release or even better CVS?
I currently have the latest packages from Debian unstable installed. (0.8.7 and 0.8.6). The pipeline I got wierd picture with before now gives no picture at all, and no error message. gst-launch-0.8 v4l2src device=/dev/video0 frequency=182250000 ! video/x-raw-rgb, bpp=24, width=704, height=576 ! spider ! sdlvideosink It just starts running and seems to do nothing. A modified pipeline: gst-launch-0.8 v4l2src device=/dev/video0 frequency=182250000 ! video/x-raw-rgb, bpp=24, width=704, height=576 ! ffmpegcolorspace ! sdlvideosink gives the same error as before, while it works with ximagesink. (By the way, why x *image* sink and sdl *video* sink?) If I modify bpp=24 to bpp=32, ximagesink gives a green-tinted image. (sdlimagesink still gives mostly noise.) This isn't an important bug to me, as I just used this pipeline test v4l2src. My interest is in piping v4l2src into theoraenc. (But that's too slow until theora gets MMX code.) -- Niklas
Don't use spider for testing. I can explain you why it does what it does but you don't really want to know, I assure you.
Ronald what is the status here? Is there a bug to fix somewhere in sdlsink etc.? Or is it a spider issue resolved by using decodebin instead of spider?
closing.. please reopen if it's still an issue. Check also the new sdlvideosink in 0.9.