Multichannel audio and multiple video file sync

[visionmill]

Thanks Ryan,

I have the clip with audio on layer 1, set to sync ID1. Layer 2 has the other clip which is set to play mode 80 Sync to layer 1. For testing purposes both clips have the same visual content which is fast moving with full screen white flash frames.

When I use one of the PL Audio modes, layer 2 does quite a bit of re-sync thought out the clip and it looks like there is about 2 frame difference between them - it is certainly lagging). There are no audible drops that I can hear.

When the play mode is set to a normal play mode then there is maybe one or two re-syncs in a ten minute clip and generally the sync looks much tighter.

In QT the clips are showing a 74mbit/s data rate - they are pro-res LT. I wondered if it was a data rate issue (even though they are coming off an SSD) so I fitted another SSD and have one clip on drive 1 and one on drive 2. This makes no different.

I also made a clip that was 3840 x 1080 to see if that was better - setting layer 2 to user layer 1. Again the audio was fine but the content looked like it was running at 20fps - just a bit sluggish.

Any suggestions?

I'm running on a 12 Core Mac Pro / 16Gb / Radeon 5870 /10.6.8 / Crucial M4 512GB SSD / Cat 4.4_m364

Thanks

Jonathan

[SourceChild]

When I use one of the PL Audio modes, layer 2 does quite a bit of re-sync thought out the clip and it looks like there is about 2 frame difference between them - it is certainly lagging)

Something that was not mentioned is the difference between 29.97 and 30 frames per second.

It is very likely your Video file with Audio is rendered at 29.97fps. Since the audio play mode becomes dominant, it will force 29.97fps. However, the other files (on a cat at 60HZ) will be running at 30fps until a sync is lost and then jump to the correct frame. This will look like stuttering in your playback.

In this situation, re render the file as mention at a very low rez black and have this as a blind layer playing audio (yet with the video set at 30fps). Then your slave layers (same or different machine) can sync to this and as slaves, should sync appropriately.

[Spam Butterfly]

Peter,

I only use dual quad cores, and have done for many years, so I can't really comment on other machines.

Hugh