Hi

Im finding the Project Monitor playback lags badly on kdenlive 0.8 when trying to edit 1080P videos, in particular MP4 1080P videos. Doing any cutting or picking a new playback point the frame rate drops to about 1 frame per 5 secs, so makes it next to impossible to edit. After about 20-30 secs it will pickup the pace and resume normal playback speed. Audio playback is unaffected.

I have tried various different options on the Video Driver, and also with OpenGL for video display enabled and disabled. Nothing has made a difference.

System Specs
Ubuntu 11.04 x64 (also tried in Ubuntu 10.10 x64)
CPU: AMD 1100T (hex core 3.3GHz) overclocked to 3.8GHz
Graphics: Nvidia GTX560 Ti
Memory: 8Gb DDR3
Harddrive: OCZ SATA2 Solid State Disk

You can guess that with machine specs like this Im not used to anything lagging.

With the older version of Kdenlive on Ubuntu 10.10 (sorry I can't remember the version number) there was no issue with Project Monitor playback of 1080P MP4 videos.


Is there a particular Video Driver with OpenGL On/Off for the video display setting that I should be using?
Or will upgrading to the development PPA solve the issue?

Thanks

Latest SVN (5772) (0.8.2)

Do not have a machine with your specs, but then I'm working with avi DV PAL 16:9 (720x576) & am noticing very similar behaviour (though less chronic).

It really cuts at transitions: the transition will look completely wrong on Project Monitor playback. Checking it frame-by-frame (right-arrow cursor) it is fine, plus the rendered product is OK. Somehow, the playback is getting utterly screwed up.

Final item is the behaviour when `play' is pressed: playback will stutter badly for 2/3 seconds then pickup. I enabled Proxy clips precisly to avoid this, yet it has made zero difference.

I can't even get proxy clips to work.

Just tried with the latest SVN build but it made zero difference.
I'll go and raise a bug report...

There were changes in MLT to allow more frame-dropping to help keep the audio more continuous. Thus, when you say "it really cuts at transitions," it is now intentionally dropping due to the processing overhead of the transition. Previously, the frame-dropping was very severely throttled, and audio would easily get choppy. However, I am not yet convinced this new mode is necessarily more desirable for video editing. The feedback I am getting here is helpful.

This change did introduce the issues you mention, and I addressed them (in MLT) on June 25. When you say "latest SVN" does that also include MLT?

P.S. proxy clips for SD DV is futile. DV is much better for editing than MPEG-2.

I have the same problem with my HD videos. I can't use any effet nor any transition, because the computer get slow speed at these moments and it's impossible to view and to undersand the effect.

my computer :
CPU INTEL CORE i5 2500
MEM DDR3 4G 1333
Video Card NVIDIA ENGT430 1Go
HH SATA III 1To

Kdenlive 0.8
MLT 0.72

GNU/LINUX UBUNTU 10.10 (2.6.35-30-generic-pae)

Thank you and best regards
JJM

I just changed this back to the old threshold of a maximum 5 consecutively-dropped frames and made it configurable (at mlt level, potentially for different applications).

Thanks for the update ddennedy.
Yes I was using sunab daily PPA in Ubuntu which included latest MLT.

Just tried it out quickly with todays build
mlt 0.7.3+git20110710
kdenlive 0.8.1+svn20110710

It was absolutely perfect, no lag on audio or video.
Awesome thanks :-)