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Instead of video got white bg with compressor

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Emanuel Ach
Instead of video got white bg with compressor
on Jan 27, 2011 at 9:42:12 pm

Hi,

I exported a video from FCP send it directly to Compressor 3.5.4. I did it so many times with this preset of settings we use here and I didn't get this problem until now. The video was 29 min, and instead of the actual video I got white screen/background for 29 min. The audio is perfect though.

Going back to final cut without changing anything to the actual sequence, send it again to Compressor and this time worked fine. I have both video and audio.

Now it get's even stranger: both files (the white screen one and the 2nd one) have the file of the size 1.44 GB. And of course same total of bitrate :6,384, same codec, MPEG-2 Video. It would make sense since it's the same preset of settings, but why in the world will an actual white screen take as much as an actual video? Even if the bitrate will be constant it still wouldn't make much sense.

Now the actual question is this, what's with the white screen and how can I prevent that in the future? I prefer not to export first and send to compressor after, because of disk space and I need to still be able to use FCP I cannot wait for it to export. Plus if I export I would be tempted to use adobe encoder which is faster (than compressor without cluster).


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Emanuel Ach
Re: Instead of video got white bg with compressor
on Jan 28, 2011 at 8:36:39 pm

I still need help with this! :)


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Craig Seeman
Re: Instead of video got white bg with compressor
on Jan 28, 2011 at 10:40:26 pm

Personally I gave up trying to send from FCP directly to Compressor a long time ago. It was unreliable. This going to be very hard to trouble shoot if you can do it twice in a row without changing anything and you get white one time and video the next.



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Jeff Greenberg
Re: Instead of video got white bg with compressor
on Jan 29, 2011 at 7:21:53 pm

If you throw ANY video into a compression tool and give it a given bitrate, it will ALWAYS result in a file of approximately the same size. Whether the frame is white, black or all the colors in between. Imagine you record with your camera with the lights off. The captured file from tape is the same exact size - because it's still recording data.

As far as your white frame? No idea - but the scale - if it's the same data rate, for the same # of seconds = same file size.

Best,

Jeff G

Apple Master Trainer
Avid Cert. Instructor DS/MC
Avid & Color Videos Vasst.com
Compressor Essentials Lynda.com


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Craig Seeman
Re: Instead of video got white bg with compressor
on Jan 29, 2011 at 9:46:27 pm

Well........ not always.
Some encoders are more "intelligent" than others.

A while back I was running some tests for HD H.264 delivery to DGFastchannel. They specifically asked for Apple's H.264 at a given data rate.

I tested with Apple's and also used tools that used Dicas, MainConcept, Matrox MAX.
They all produced data rates WELL BELOW Apple's H.264 although they all had essentially the same settings and certainly the same target data rate. What happened is that the slate and black slugs lowered the bit rate in the more "intelligent" H.264 encoders. They didn't use bits that were not needed for text over stationary background or black. This has to do with codec efficiency and it's why Apple's is about the least efficient H.264 in use.

BTW I confirmed this by removing the slate and black slug and the resultant data rates were much closer to each other.

Basically an efficient codec will generally not use unnecessary bits to maintain a targeted data rate. They will tend to undershoot in such circumstances. This seems especially so when targeting higher data rates.



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Emanuel Ach
Re: Instead of video got white bg with compressor
on Mar 19, 2011 at 5:58:24 am

It happened again, guys is it possible to be something with the Mac?

Its mac leopard latest version with updates everything, so does final cut 7 has all the updates. I will call Monday Apple, I will lose my job if they keep making crappy software.

I mean im only running Apple software there...


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Emanuel Ach
Re: Instead of video got white bg with compressor
on Mar 19, 2011 at 6:15:39 am

it's mac snow leopard sorry, it's too late in the night here :)


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Jeff Greenberg
Re: Instead of video got white bg with compressor
on Mar 19, 2011 at 12:23:34 pm

So, just restating your problem:
If you send something from FCP to Compressor, sometimes it ends up in a white screen?

Sounds like there's a problem with the communications between the two.
Workout (not a fix): export a QuickTime (not QuickTime conversion) and put that in compressor.

The fix? It's an odd problem:
What kind of footage is it?

Best,

Jeff G

Apple Master Trainer | Avid Cert. Instructor DS/MC
Come See me speak at NAB!
Compressor Essentials from Lynda.com
(older but still good) Marquee, Media Composer (3.5) and Basic/Advanced Color DVDs (1.0) from Vasst.com
Contact me through my Website


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Emanuel Ach
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 5:34:22 am

because we can only do that at the end of the day we have to either export and next end of the day compress (unless there is a way to schedule compressor somehow) or to send it directly to compressor and skip one step and get it faster.

The original stuff is DV in mov files... and we are compressing as mpeg2

Thanks


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Jeff Greenberg
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 2:34:14 pm

I was restating your problem to make sure that I understood it.

"If you send something from FCP to Compressor, sometimes it ends up in a white screen?"

Is this correct? If not, then please try communicating it again.

Best,

Jeff G

Apple Master Trainer | Avid Cert. Instructor DS/MC
Come See me speak at NAB!
Compressor Essentials from Lynda.com
(older but still good) Marquee, Media Composer (3.5) and Basic/Advanced Color DVDs (1.0) from Vasst.com
Contact me through my Website


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Emanuel Ach
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 5:25:54 pm

Yes it's correct.

Thanks,
Emanuel


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Brian Walker
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 4:46:43 pm

I would only export a reference file of the clip and drop on compressor to compress into mpeg2. It is quick, and you can still work in FCP while compressor is doing its thing. The way you do it ties up both FCP and Compressor and sounds like it is unreliable. Good luck!

Thanks in advance!
Brian Walker


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Emanuel Ach
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 5:33:07 pm

In FCP 7 when you send it to compressor it does everything in the background. I could still work on editing in FCP while compressor does it's thing. Because we are talking here about a lot of videos (hundreds) I might not have enough space to export everything from FCP and compress after. Plus it will take me double time to do that, unless I can schedule compressor to run after FCP exports everything.

Even if I export reference I cannot use final cut during that time right? Is the size going to be the same as a normal mov file exported from FCP?

However, we have here a few macs and this problem I only got the white videos from one particular MAC twice. It's got snow leopard, as I stated earlier everything is updated, especially quicktime. I also have quicktime pro 7 installed besides the regular one. The settings are everytime the same, it's a preset custom saved, I don't touch it never for those kinds of videos. So one time it gives me white, the next same settings it's good video. Strange. Should I call apple?


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Brian Walker
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 5:40:29 pm

You can "batch export" all you sequences at the end of the day to compressor and let them compress overnight. When you export a ref file it is a lot smaller file that points to the original media. Takes a lot less time and space, BUT, it is a ref file... If the media is deleted or moved your ref file is no good! Beware...This is not meant to be a digital master, if you need a digital master of each seq, just check the box that say "make self contained" I am only mentioning a different workflow because I have had problems doing it your way, and have had none when I switched to the way I mentioned... Good Luck!

Thanks in advance!
Brian Walker


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Jeff Greenberg
Re: Instead of video got white bg with compressor
on Mar 20, 2011 at 6:11:14 pm

Can you reproduce this?

In other words, does the same video always give you white....or is it random. Sometimes the same video sent over twice will give you a correct encode....or sometimes a white screen.

Meanwhile: apple on resetting compressor

Best,

Jeff G

Apple Master Trainer | Avid Cert. Instructor DS/MC
Come See me speak at NAB!
Compressor Essentials from Lynda.com
(older but still good) Marquee, Media Composer (3.5) and Basic/Advanced Color DVDs (1.0) from Vasst.com
Contact me through my Website


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