Tearing when playing a movie in QC 4.5 (lion)

itsthejayj's picture

Hi guys

I'm noticing a horrible video tearing(?) in QC 4.5 (lion), tested on the stock movie loader, video tools, and v002 movie loader. Its present on ALL of my videos when played within QC. I have tested the videos directly in QT with no problems(tearing).

Does anyone have a solution here, is anyone else experiencing this?

I've attached an example video, a composition. Below is a link to the live video capture of what i see as screen capturing doesn't show the problem!

http://www.youtube.com/watch?feature=player_profilepage&v=c9MNEVyW6js

MBP Processor 2.66 GHz Intel Core i7 / Graphics NVIDIA GeForce GT 330M 512 MB / Software Mac OS X Lion 10.7.2 (11C74)

PreviewAttachmentSize
movie_tearing.zip11.03 MB

smokris's picture
Re: Tearing when playing a movie in QC 4.5 (lion)

It's difficult to see any difference with the cameraphone (?) video you uploaded...

Curious, do you have disableVBLSyncing checked in the QC Editor's PrivatePreferences? (See that wiki page for details.)

cybero's picture
Re: Tearing when playing a movie in QC 4.5 (lion)

I had paused before posting as you referred to a stock patch that I no longer have effective access to in the QC environment. It's a bug is that one. Already reported elsewhere [long ago] and still unremedied. Reading through your post again I see you also have the same problem within other Video patches.

I cannot reproduce your reported problem with those non stock Video patches on 10.7.x. That is with or without flagging Disable VBL Syncing in Private Preferences.

I'm just glad those non stock patches are still around and give effective access.

I half suspect that your problem is potential evidence of their being an underlying imperfection to the hardware driver.

Is there another video process concurrently open whilst you are rendering in QC?

itsthejayj's picture
Re: Tearing when playing a movie in QC 4.5 (lion)

Ah problem fixed by changing the diableVBLSycing, pretty sure I haven't been playing around with the private preferences in QC lion so a tad confused, but hey problem solved thanks guys

itsthejayj's picture
Re: Tearing when playing a movie in QC 4.5 (lion)

So the improved frame rates with disableVBLSyncing on my system are incredible. Although the horizontal banding is annoying is there anyway to disable VBL syncing in a qcview or qcrenderer?

cwright's picture
Re: Tearing when playing a movie in QC 4.5 (lion)

itsthejayj wrote:
Although the horizontal banding is annoying is there anyway to disable VBL syncing in a qcview or qcrenderer?

QCRenderer doesn't enforce VBL sync (that's a function of the CGLContext you're rendering it into). QCViews don't have a supported way to disable VBLSync.