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Pro Tools - Avid Video Engine Offline Bounce To QuickTime Bug

While beta testing the brilliant new Video Slave 3 yesterday, we came across a major bug in Offline Bounce To QuickTime in both Pro Tools 11 and 12.

We were finding that QuickTime Bounces made using Pro Tools would not open the same way using different software.

It all revolves around what most audio engineers would consider "black". Most would consider it the same as audio silence, but there are circumstances where that comparison doesn't work.

Mind The Gap

If you have any gaps between video media on your timeline - the Avid Video Engine actually treats it as missing media - not as black, and gives some rather peculiar results, depending on what software you use to play them with.

So say I wanted to send out a QuickTime with two versions of this trailer mix, one after the other, with a ten second gap between them and a ten second buffer at the beginning.

If I import the result back into Pro Tools, there are two ways it can go. Either it will have it as starting at 10:00:00:00 (the start of the video media) and will not have the ten second buffer on the front, or there will be ten seconds of freeze frame at the front.

It will also have random freeze frames between the two video media clips, where there is meant to be a gap of "black".

Opening With QuickTime Player, Video Slave or Premiere Pro

If I open the resulting video bounce in QuickTime player, it plays correctly, with the ten second black buffer at the beginning, and the black spacing between the videos.

If I open it in Video Slave from Non Lethal Applications, it sees the buffer at the beginning and the gap in the middle, but the timeline timecode is severely messed around with at the beginning and during that gap, meaning that videos produced via Offline Bounce To QuickTime which have blank media, will not run in sync within VideoSlave.

If you load the same video into Adobe Premiere Pro, then there are all sorts of random corruptions where there should be black. This is the most surprising, as I've generally found so far that Premiere Pro will happily import nearly anything.

Why Does It Play Properly On QuickTime But Nothing Else?

This is because despite having the Avid Video Engine to handle video playback from version 11 onwards, Pro Tools still outsources lossy video (and audio) processing to the QuickTime engine.

This is why this option is labelled "Bounce To QuickTime", rather than "Bounce To Video".

As discussed before, QuickTime was deprecated by Apple many years ago now, and was severely limited for Windows users, which is why Avid incorporated a cut down version of the Avid Video Engine in to Pro Tools once it went 64bit.

However Avid still rely on QuickTime for re-embedding audio back i to video files after a bounce, and for exporting and importing lossy audio codecs such as MP3.

How Does This Impact Pro Tools Users?

I've heard reports from a fast turn-around episodic drama production, that this has caused problems with their workflow.

When as quite often happens, there is a recut after sound post has begun, often the supervising sound editor will re-conform both the master audio tracks (usually dialogues) and the video track, then do an offline bounce to File and QuickTime, to be sent quickly on to the other sound departments (foley, ADR, etc), so they can track the changes.

In this case this problem has lead to issues with other departments who are meant to be working in tandem, particularly if they don't use QuickTime to view the video files.

Give Us A Proper Video Engine!

It's my opinion that Avid should have ditched their reliance on Apple software a long time ago. They had the opportunity with 64bit and Pro Tools 11 onwards to make a clean break, but they decided to still hang in there.

This is causing a multitude of problems, both with this issue, and with multichannel audio embedding (incorrect / non specifiable track layout).

It is also my opinion that Avid have got distracted by Cloud Collaboration, and by trying to please the two extremes of the market - hobbyists and mega facilities, have massively dropped the ball when it comes to the middle - the small facilities and work from home professionals.

Here's hoping something gets properly sorted out for us "middlemen" soon.

Come on Avid!

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