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Terrible Banding in h264 Export (low light film)

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Jackson Parrell
Terrible Banding in h264 Export (low light film)
on Aug 14, 2011 at 6:51:01 pm

Hey everyone, hoping somebody might be able to help me with some compression guidelines or tricks for getting my short film to look half decent in an h264 export.

The problem is that the film is a very dark. And Im finding that even in my 4444 master theres a small amount of banding, and in the h264 its so bad the image is completely unusable. I need this to look presentable at 5000kb/s for vimeo and similar uses. The problem is pretty clear from the examples i've posted. My workflow was RED>FCP>COLOR>Prores 4444>comp comp

Im assuming my compressor is throwing away by default allot of the black information because it usually isn't a problem, however in this particular film that won't do. Are there any compression programs or settings i should be using to remedy this problem? Any help would be much appreciated as this film is essentially useless to me if it can only be played as a prores4444 file haha.





i'll upload the whole 5000kb/s to vimeo and post that aswell if that helps.

THANKS!


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Jeff Greenberg
Re: Terrible Banding in h264 Export (low light film)
on Aug 14, 2011 at 8:56:56 pm

What/where are you going to do with the h.264 export.

You're struggling because you shot in 12 bit, edited in 10 and are dumbing down to 8 bit...and surprise - there are only 256 steps from black to white. Therefore, you end up with banding.

Even upping the data rate probably won't help, but hell, throw 50megs/s @ the h.264 and see if that improves anything.
Also, take a minute of footage and export from FCP as an uncompressed 8 bit file. If that doesn't work, nothing will @ 8 bits.

Best,

Jeff G

Apple Master Trainer | Avid Cert. Instructor DS/MC | Adobe Cert. Instructor
------------
You should follow me (filmgeek) on twitter. I promise to be nice.
New- my book (with Richard Harrington and Robbie Carman)- An Editor's Guide to Adobe Premiere Pro
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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Jackson Parrell
Re: Terrible Banding in h264 Export (low light film)
on Aug 15, 2011 at 2:56:13 am

I'm using the h264 for viewing on my website. Preferably through vimeo.

I've read that adding grain to the image can help reduce the banding, im experimenting with that rite now. There is actually one section of the film that was worked on by a compositor, who i believe added a small amount of grain to the image, and as a result the banding in this sequence is very minimal compared to the rest. Is this something that will work? i'd obviously prefer to solve this in a way that doesn't involve degrading the image though.


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Jeff Greenberg
Re: Terrible Banding in h264 Export (low light film)
on Aug 15, 2011 at 10:33:04 am

Well, wait - did you try what I suggested or not? You don't have to compress the whole thing - you can set in/out points in FCP, Compressor etc, and just test the troubled shot. I'd suggest seeing how it looks in 8 bit uncompressed HD (huge file) before you go any further. Any tests you do? You should do before compression.

Yes, you could try adding noise - essentially it's 'dithering' the image to a degree. This may require a higher bitrate.

Best,

Jeff G

Apple Master Trainer | Avid Cert. Instructor DS/MC | Adobe Cert. Instructor
------------
You should follow me (filmgeek) on twitter. I promise to be nice.
New- my book (with Richard Harrington and Robbie Carman)- An Editor's Guide to Adobe Premiere Pro
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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Jackson Parrell
Re: Terrible Banding in h264 Export (low light film)
on Aug 15, 2011 at 2:19:06 pm

I've done two tests, one where i took a segment of the original pro-res 4444 and added grain in after effects, exporting under its animation preset and then going to 5000kb/s h264 in compressor.

and another where i took the same segment of the pro-res 4444 and compressed it to 8bit in compressor.

The 8 bit had noticeable banding however considerably less then what im used to seeing with my low bit rate h264's. i guess id consider this an acceptable level.

and the clip i'd added grain too looked a whole lot better in h264 then the equivalent conversion without grain, however not quite as good as the 8bit

i should add that i don't have the origial fcp file and scratch disk for this film. just the pro-res 4444 that i exported from fcp and color. although im considering getting my hands back on it and starting from the top again. maybe add grain in color and export as a 10bit? then dumb it down?


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Jeff Greenberg
Re: Terrible Banding in h264 Export (low light film)
on Aug 16, 2011 at 12:01:48 pm

Well, the ProRes 4444 file is 10 bit and has enough starting information.

And the 8 bit unc looks 'acceptable.' Great.
About the best you can do at this point is see how much compression to h.264 works - both with and without a grain.
I'd start @ 50mb/s h.264 and drop it by 5mbs increments both with and without a grain until you get a version your happy with.

And, what the hell, if you go back, regrade the scenes and brighten up the scenes (I know, heresy!), it'll probably compress better.

Best,

Jeff G

Apple Master Trainer | Avid Cert. Instructor DS/MC | Adobe Cert. Instructor
------------
You should follow me (filmgeek) on twitter. I promise to be nice.
New- my book (with Richard Harrington and Robbie Carman)- An Editor's Guide to Adobe Premiere Pro
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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