I'm also wondering about an oddity I'm seeing where when using the /dev/video48 device, video looks like we are missing frames, it's jerky on playback. It didn't do this originally when I first was getting it to work, suspect we need to possibly really program all the buffer registers to make it work smooth, although I think I didn't have to do that, something seems wrong (not sure if the ioctl is doing this, suspect it isn't). Also the ghosting image over the top of playback, never happened originally, was perfect pictures, now it's doing that, I don't know, maybe again the buffers needing to be all programmed or something.
So that's my current thing I'm seeing and trying to figure out, can't see where the code changed enough to switch behavior, but hard to tell since YUV decoding is just tricky and still setup/teardown is so hackish. Thanks, Chris On Wed, May 18, 2005 at 01:50:31PM +0100, Matthew Hodgson wrote: > So, I decided to give John Harvey's exciting YUV decoding patch a go on > 0.3.4p - and so far it's all working fairly well :) I've had a few > problems, though, which I thought I'd share: > > a) I'm feeding the decoder 25fps progressive PAL video to /dev/video48. > However, the YUV decoder renders both fields of each frame using only the > odd field's buffer (i.e. lines 1,3,5.. counting from the topmost line being > 1). This obviously halves the vertical resolution of the luminance, which > makes the visual quality considerably worse than the OSD - especially > noticeable on aliasing artefacts in animation. This occurs after > initialiasing the MPEG decoder with a typical MPEG2 recording sent to > /dev/video0. > > b) For the first time after being initialised with a bit of MPEG stream, > the YUV decoder works otherwise fine - but after another MPEG stream is > decoded YUV decoding subsequently only displays a black screen until the > next module/firmware reload. The IVTV_IOC_PREP_FRAME_YUV returns without > errors, however, and the kernel log debugging at ivtv_debug=63 reads the > same before & after. > > c) If you initialise with half-resolution MPEG-1 content, the YUV stream is > also displayed at the same scale, so you only see the top-left quadrant of > the screen. > > Any ideas on how to get both YUV fields displayed by the decoder, or > confirmation of these problems with other people's setups would be of great > interest :) > > M. > > > ------------------------------------------------------- > This SF.Net email is sponsored by Oracle Space Sweepstakes > Want to be the first software developer in space? > Enter now for the Oracle Space Sweepstakes! > http://ads.osdn.com/?ad_id=7412&alloc_id=16344&op=click > _______________________________________________ > ivtv-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/ivtv-devel -- --- Chris Kennedy / [EMAIL PROTECTED] Engineer KMOS-TV/KTBG-FM Broadcasting Services Department Central Missouri State University ------------------------------------------------------- This SF.Net email is sponsored by Oracle Space Sweepstakes Want to be the first software developer in space? Enter now for the Oracle Space Sweepstakes! http://ads.osdn.com/?ad_id=7412&alloc_id=16344&op=click _______________________________________________ ivtv-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/ivtv-devel
