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FLV setting for rapid movement

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David Modijefsky
FLV setting for rapid movement
on Nov 24, 2009 at 12:41:38 am

Hi there,

I have this pesky clip of about 6 minutes that starts with a zoom from sattelite view to a city scene at almost street level. This zoom takes about 6 seconds and with my normal encoding (FLV, 1Mbit streaming) the video goes out of sync. The rest of the clip has modest movement so the problem is really in the start. The screen stays black for about 4 sec while the audio already plays. Whatever setting I make, the video pops up only after around 4 secs. I've tried to mess with the audio settings as well but nothing seems to work.

The original clip is a progressive H-264 QT and the frame size after encoding stays the same: 340x 191. My settings so far are :

Video >Flv
Average framerate: 900 kbit/s
VBV buffer size: 10
Natural & Forced keyframes: 40
2-pass interval: 200 frames

Any ideas on how to fix this? Thanks in advance!


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Craig Seeman
Re: FLV setting for rapid movement
on Nov 24, 2009 at 12:57:07 am

What compression app are you using? It looks like it might be something like Episode.2

[David Modijefsky] "The original clip is a progressive H-264 QT"
Which probably has AAC audio. Can you try with the source file used to create that H.264 QT? Compressing an already heavily compressed source should be avoided. Generally I find GOP based sources to be prone to more issues as well.

[David Modijefsky] " the frame size after encoding stays the same: 340x 191"
I'd avoid odd frame sizes like that as well.
http://www.adobe.com/devnet/flash/apps/flv_bitrate_calculator/video_sizes.h...





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David Modijefsky
Re: FLV setting for rapid movement
on Nov 24, 2009 at 9:50:04 am

Thanks Craig. Yes, I'm working with Episode 5.2. The H-264 clip's audio does not have AAC, just normal/ big endian @ 48000Khz. I'll ask for a lossless version @ 44.100Khz. Should that do the trick? Because the other H-264 clips I worked with did not cause any problems.

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