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H264 files show different content when posted to the internet

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ivy calhoun
H264 files show different content when posted to the internet
on Jan 19, 2011 at 11:24:15 pm

Hi,

We've been having this strange issue for a while and I figured it's time to ask the CC gods. The issue is, when we cut slates off of spots and export H264 files in QT (and sometimes even when we do it in final cut), then post the files to say youtube or our wiredrive, a still from the slate will show up as the thumbnail or the slate will just reappear completely in the video. Does anyone know why that might be??


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Olin Padilla
Re: H264 files show different content when posted to the internet
on Jan 19, 2011 at 11:42:01 pm

Interesting problem. Is it possible that the still is in the meta data and not the cut itself?

If the entire slate is appearing in the uploaded video, then my assumption is that Youtube is not updating properly, and is using an older upload. I've seen this type of thing happen before.


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ivy calhoun
Re: H264 files show different content when posted to the internet
on Jan 19, 2011 at 11:47:18 pm

Thanks Olin,

2 things.

1)Would the slate have to be manually put into the metadata? Is that possible? And if so is there a way to dig that part out?

2) On the youtube part. Unfortunately it can't be that there was an older post. We are always uploading an original file; there's never a slated version uploaded, in our case.

Perrrrplexing!

Thanks again


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Olin Padilla
Re: H264 files show different content when posted to the internet
on Jan 20, 2011 at 12:20:44 am

I honestly don't know how the slate information could even exist if it was removed and exported as a self contained movie.

As a solution, I would try removing the slate and exporting the video as a separate step from the h264 encoding. A codec like prores will only use i-frames, and therefore there should be no chance of the video containing information from previously existing frames.

Also, you might want to try creating an mp4 instead of an mov, since that is the format that Youtube uses for higher quality video. With MPEG Streamclip, you will have the same codec flexibility that you have with mov in compressor. I'm not sure if that would help, since Youtube will probably re-compress it anyway.

Does anyone know if there is a way to override the Youtube compression?


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Craig Seeman
Re: H264 files show different content when posted to the internet
on Jan 20, 2011 at 12:44:29 am

Edit slates in an NLE. Maybe there is a single frame at the head or a flash frame in the body you're missing. I can imagine something like that happening if you're dealing with interlaced and watching on a progressive monitor. Trim one more frame on either end in the timeline. Export self contained in the timeline codec Check that file. Compress in Quicktime. Check that file. Upload to YouTube. Check that.



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Rich Rubasch
Re: H264 files show different content when posted to the internet
on Jan 22, 2011 at 9:39:20 pm

I'll bet Ivy is opening the main movie in QT player and selects an in and out. Then she copies the selection and pastes it into a new empty player window. Then she exports from that new clip. Sounds fine right? Well, by pasting into a new window she has only made a reference clip from the original, so in fact the slate is still part of the entire stream that the new clip can see.

In MPEG Streamclip you can mark an in and out and export only that portion of the movie and that new movie will not contain any trace of the original. I'll bet if she saved the new ref clip to a new self contained movie, then opened that one and exported to her final the mysterious slate would be gone.

Try it and please report back.

Rich Rubasch
Tilt Media Inc.
Video Production, Post, Studio Sound Stage
Founder/President/Editor/Designer/Animator
http://www.tiltmedia.com


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