This IS the Avid L2: Re: [Avid-L2] QT File from Avid through QT Pro chops beginning audio in FCP7?

Friday, October 2, 2015

Re: [Avid-L2] QT File from Avid through QT Pro chops beginning audio in FCP7?

In further tests I've found that the files that FCP7 misses the initial 12 frames of audio all play fine in VLC, MpegStreamclip, Adobe Premiere, Avid when ama linked, ProTools. When using Mpegstreamclip I had to use QT Pro movie properties to disable the tracks 1 and 2 from the L,R,C,Lfe,Ls,Rs,Lt,Rt audio in the .mov so I could here the stereo Lt, Rt from tracks 7&8. VLC lets you select any one of the 8 channels to play out the computer speakers.

Now I'm curious what is the proper choice for accurately QCing a .mov file? Is there one master solution that will alleviate the confusion I'm dealing with. Would something like the Black Magic utility that allows for outputting files to tape be a better choice for a QC situation or the similar software/hardware from AJA. Clearly FCP7 has shortcomings, or is it an asset, that finds fault with my file. If the only place it doesn't work is FCP 7 then I don't find that a real problem unless the network broadcasts from FCP7 and what if some other piece of software has some other issue down the line? Where is the even playing field to reference a file to?

Is this a job for something like Tektronix Cerify. I wonder if a product like that would flag an error on the file?

---In avid-l2@yahoogroups.com, <bigfish@...> wrote :

I know all the QT Ref .movs I exported were audio uncompressed. It was only the same as source Avid output that said it needed to be rendered when played in FCP 7. In Avid with a QT export same as source the only audio choice I see is mono, stereo, 5.1, 7.1 and direct. I'm on 6.5.4.7 and have always used QT ref exports as the only way to get multiple audio stems out. It's been my understanding that is still the limitation. Now that I see the direct choice here in the same as source audio options does that mean if I had 12 audio stems like for an SR tape delivery I could do a send to QT movie same as source and select direct and get all 12 audio stems as discrete mono tracks in the .mov?

From past threads here the only multi channel audio .movs exports directly from Avid were from stereo or 5.1 channels that were in the Avid timeline. Is this direct option in send to qt movie under the audio tabs mean I've been wrong all these years? I think not but given everything I know is wrong today what's the harm in asking.

---In avid-l2@yahoogroups.com, <pale.edit@...> wrote :

You probably already checked this, but are you absolutely sure you exported uncompressed audio? It's perfectly possible to export Pro Res and accidentally compress the audio AAC. QuickTime will happily let you do it and under certain conditions, it can inexplicably default to that bogus setting. If this happens, FCP will show it as needing to be rendered (the redline will actually be for the audio). It may also cause bizarre audio sync issues.

Before you ask....yes, I have encountered this problem in the past and figured it out after pulling out some hair.

On Friday, October 2, 2015, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

Your logic makes sense. What I'm more at issue with is a QC house using FCP7 as a QC tool when in this case there clearly is a deficiency in it's handling of a QT file that neither Adobe, Avid or ProTools have and more importantly the network we are delivering too doesn't have a problem with the file.

To me FCP 7 is not properly representing the files integrity but demonstrating its' own shortcomings. Given how many QC head aches I'm seeing coming from an FCP analysis and now with this new knowledge of it's problem handling of QT files relative to the others I listed I'm wondering how many of the QC flags have more to do with FCP 7 than the actual file

Given QT Pro plays the file fine and FCP7 is QT based what's going on here. Now it's time for Phillip to step in and clarify the FCP7 side of things

When they tell me the ingest server can't handle the file I listen but now when QC sees an issue like this my first question is going to be are you using FCP 7 to asses the file?

As great as the workaround of video mixdown is for Avid not to be able to export a selfcontained .mov with 12 discrete stems, or more, is really disappointing.

---In avid-l2@yahoogroups.com, <cutandcover@...> wrote :

Video Mixdown is one of the greatest things about Media Composer. It has saved so many issues for me.

That said, I agree with the frustration about hoop jumping.

Understand something about QT Ref: when you make a QT Ref, it is a shabby container with records to point to its contents. If those contents show up as multiple files per track, things can get screwy, especially sync. So when you add a piece of black at the top and tail, and silence pieces, this QT Ref now has to point to multiple chunks of video to have a contiguous track. Are you trusting the dinky QuickTime Player to put these pieces together in the order and timing that they were in your edit? Most of the time that works out. Sometimes it does not, and that percentage, however infinitesimally small it may be, is enough for me to mixdown ALWAYS. The small amount of extra time this takes is worth a thousand what-ifs in the long run.

On Fri, Oct 2, 2015 at 4:38 PM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

I also feel like a broken record in not wanting to mixdown especially on a project that came in as a full file completely color corrected from Resolve. I will check that process if all else fails. I am not disagreeing with your point but if the network QC that are the final arbiter of what will work for them doesn't have an issue with the file when we send it to them, and we have and they are fine with it, then I feel FCP7 is no longer an accurate QC tool to be used for this Network.

I was very careful to keep everything ProResHQ in this project to facilitate a simple QT reference export to maintain the 8 audio stems and a simple save as in QT Pro. Now if Avid would just fix their broken export of multi channel audio I wouldn't have to jump through these hoops at all. This seems like such a priority issue with file based delivery more the norm for many projects. Come on Avid.

I'd really like to know WTF is going on under the hood so somebody can fix it so I never have to hear that ugly phrase Video Mixdown again. ;-)

Seriously given the Pixel scrutiny I've been dealing with on this project the last thing I want to do is introduce another layer of rendering a video mixdown that could somehow induce any errors to the image. I know there shouldn't be any traditional generation loss in a video mixdown but it is adding another video process to the the food chain and that does introduce another thing that could possibly introduce pixel issues. Believe me these are so small and non issues I can't believe I'm fixing them in the first place.

---In avid-l2@yahoogroups.com, <cutandcover@...> wrote :

I feel like a broken record here, but I'll go again:

MIXDOWN, then export QT Ref

If you are not mixing down first, you might run into problems. The last part of that sentence is enough for me never to chance it.

I won't guarantee that FCP7 will be happy for any of this, but I will guarantee that a video mixdown is the real and true solution to any problem stemming from bouncing through references.

On Fri, Oct 2, 2015 at 4:14 PM, John Moore bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:

Having QC issues on a file that is fine on my end until I put it into QT Pro 7.

Have a sequence that is all ProResHQ. I added a black title at the beginning for the 1 sec pad and a black title at the end for 1 sec tail pad. I added audio silence from the Protools stems at the end 1 sec pad. Everything is rendered to ProResHQ. The show is 99.9% a long ProResHQ 422 sent from Resolve. The audio is 8 tracks of ProTools Stems 5.1 plus LtRt.

I export a QT reference from Avid then Save As in QTPro 7 after naming the 8 mono tracks to their channel postitions L,R,C,Lfe,Ls,Rs,Lt,Rt. The resulting file plays fine when Ama'd back and if I send it to ProTools it's correct. QC using FCP7 is missing the first 12 frames of audio after the 1 sec head pad when they view it in FCP 7. I can duplicate this behavior on my system. If I chop off the 1 sec head pad all is fine in FCP 7.

I went back and added the same 1 sec of silence media I added under the tail 1 sec pad to the head 1 sec pad but still the resulting self contained .mov is missing the first 12 frames of audio when viewed in FCP7. I can take the same file into Adobe Premiere CC2014 and the audio is fine. The head pad is a black title created in Avid as proreshq and rendered to proreshq. Like I said at first I had no audio media just filler but now with silent media there is still the issue in FCP 7

I have finally gone back to the Avid sequence and found there was 1 sec pad at the head of the audio stems and added that back in sync so the audio is one long chunk followed by the 1 sec silence media from the same stems placed at the end. Even this export has the issue in FCP 7. My last resort will be a full same as source export from Avid but this will then mixdown the audio so I will have to remarry the stems in QT Pro7. I will try just the resulting stereo audio file in FCP7 first to see it this behaves properly but I won't know till after the export.

Bottom line it appears that FCP 7 is no longer a viable way for QC houses to check files IMHO. Nothing after the missing audio is out of sync so what is FCP 7 doing to lose this audio. It seems to be related to the 1 sec pad at the head but I can't seem to nail the real culprit. Any suggestions welcome.

John Moore Barking Trout Productions Studio City, CA bigfish@...