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FLV + Light Colors = Bad Output

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Drew Jensen
FLV + Light Colors = Bad Output
on Aug 24, 2010 at 2:41:24 pm

Hey everyone, this is sort of an odd thing I noticed and I couldn't find anything in the forums dealing with this issue. There might be something but I didn't really know exactly what to search for so what I did search for, didn't find anything. Anyways... to the issue. When I'm encoding people (HDV->FLV), I've noticed that subjects who are wearing lighter colors, usually mixed with some type of white (white dress w/ black poka dots), the whole subject is more pixelated than a subject with darker colors (dark blue shirt w/ suit). FYI this is on green screen, which I know HDV= not good, but it's what I have to work with for the time being. The subjects are moving the same amount(swaying and hand movement), both are encoded to same bitrate and exact same setting for the output and input. Both source videos look to be exactly the same. So I'm wondering if this has something to do with flv's interpretation of the overwhelming amount of white or what? I didn't think it was the white balance, because that was set at the morning of the shoot. No ambient light from any source other than ones that were set up and on all day. I've had this issue with other subjects who are wearing clothes that are majority white, where as I get nice looking output w/ those who are wearing dark suits or dark shirts. So to sum it up, all setting are part of the control and the only thing that changes are the color of the subjects clothes. Thanks for the help.

Drew Jensen


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Craig Seeman
Re: FLV + Light Colors = Bad Output
on Aug 24, 2010 at 2:54:58 pm

Please read the sticky at the top of the forum
How to get FASTEST compression help - PLEASE READ

Otherwise we're left with doing a lot of back and forth which will waist a lot of time.



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Drew Jensen
Re: FLV + Light Colors = Bad Output
on Aug 24, 2010 at 3:01:25 pm

My apologies

Computer - Windows Core i7 920 12GB Ram
Operating system - W7 Ultimate 64bit
Software - After Effects 9.0.2.42
Source codec - Capture in HDV 1080i 29.97fps via Premiere Pro
Destination codec - .FLV 320x320 200kbps
Type of destination use - web streaming

Drew Jensen


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Craig Seeman
Re: FLV + Light Colors = Bad Output
on Aug 24, 2010 at 4:22:49 pm

[Drew Jensen] "Destination codec - .FLV 320x320 200kbps"
On2VP6 I assume rather than Sorenson Spark (both are .flv).

Try 2 Pass VBR instead of CBR.
That's a very low data rate and extremely small frame size. I'm not sure why you have such a severe limit.
If you must stick to those numbers lower frame rate to 15fps which give you more bits per pixel per frame.
Better would be to increase the data rate.
These days I really wouldn't go below 480x360 frame size either but of course that means a commensurate increase in data rate.

I'd also recommend using H.264 .mp4 which has been Flash compatible since late 2007 unless you are targeting very very old computers for some reason or are preserving an alpha channel.

A recent study by the FCC (USA) noted that the median download speed is 2000kbps.

Slowest connections I know of are 384kbps or 768kbps down but certainly it depends on your target region.



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Alan Lloyd
Re: FLV + Light Colors = Bad Output
on Aug 28, 2010 at 3:56:45 pm

I do similar types of compression for one of my mainstay clients.

It sounds like you're having "separation" troubles with your greenscreen shooting if people are wearing white or light colors.

Where is your greenscreen lighting level falling? How far is your subject from the backdrop? What are your overall exposure levels as to skin tone, etc?

Very often the trouble comes in earlier on than the compression, especially when greenscreening.

And the frame size and bitrate tells me it may well be for a corporate client.


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