[mythtv-users] Weird old-frame problem editing recordings, but only at 5+ second jumps (even after .24 +fixes upgrade)

[John Pilkington]

On 29/06/11 01:09, Kingsley Turner wrote:
> Hi,
>
> I have this problem with the MythTV video editor/trimmer thing.
>
> When I step through the video at 1-frame, 0.5 seconds, or 1 second
> everything is OK.
>
> However when I step through at keyframe, 5 seconds (or more) the image I was
> viewing before pushing [right-arrow] (or [left]) obscures the new frame
> image.  However I do see the correct frame for a split-split-second before
> the old one obscures it.  So the 'cursor' is advancing through the video,
> but I can never see exactly where I'm up to.
>
> That sounds a bit convoluted - here's an example.
>
> Say I have a news recording before a program I want to trim off.  On my
> screen I see the face of the news-anchor-dude.  I set the jump to 1 second,
> and press [->] and the cursor advance, and a new video frame is shown (it's
> still the same guy though).  All this is correct.
>
> So I up the jump time to 5 seconds, press [->].  I see a screen flash of the
> new frame, but it's immediately covered by the frame I started on (the news
> reader).  I push [->] about 10 times.  As I do it, I can see the cursor
> advance, and a flicker of the correct frame (into my nature-programme now),
> but every time that original news reader image is back.  I set the jump-time
> back to 1 second, and it works fine.
>
> I had this problem with 0.23, but had hoped it would go away with 0.24.  It
> hasn't.  It's a real problem with the keyframe jump.  I want to trim every
> last peice of the previous programme away, but this problem makes it really
> difficult - almost trial and error.
>
> I run the nvidia-binary driver - NVIDIA-Linux-x86-260.19.29.  But various
> upgrades to this driver have yielded no resolution.
>
> Any advice here?
>
> The last time it worked properly for me was 0.21
>
> thanks,
> -kt
>
My memory of this is rather hazy:  I used to see behaviour a bit like 
this with the editor, although I don't  recollect anything 
5-second-specific.  I think it had to do with the video-blitter 
settings, or maybe it was Qt vs GL.  I don't see it now, and a quick 
look at the frontend settings hasn't shown anything that clicks.

In my nVidia X server XVideo settings I have the Video Texture and Video 
Blitter both synced to VBlank on the monitor, and  OpenGL _not_ synced 
to VBlank, with flipping allowed.  These settings may not make any 
sense, but if they differ from yours they may be worth trying.

John P