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Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.

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ikarus79m
Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 5, 2006 at 7:52:18 am

I'm currently exporting a movie from Adobe After Effects (2K DPX Files) to the Blackmagic 10bit encoder with Trillions of colors. I need to encode this to H.264 for Web and HD viewing.

This is a screenshot of the exported file and how it is supposed to look:

Image Hosted by ImageShack.us

However, when I dump that file into compressor and export via the Quicktime 7 H.264 preset I get this as a result:

Image Hosted by ImageShack.us

It almost seems as if there is a gamma shift going on. Weird huh? But it gets better! When I choose to export to the IPod H.264 (VGA) setting i get this as a result:

Image Hosted by ImageShack.us

It looks like it is supposed to look!!! (Just that I can't make it any bigger because the Ipod preset won't allow that!)

I don't get this. Why is one bleached out and the other normal? Have you ever heard of this before? What software is Apple using for their Quicktime HD H.264 trailers so it doesn't happen to them?

I'd be really interested to hear your feedback!

Philipp



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Charles Simonson
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 5, 2006 at 8:09:39 am

Is that the new iPod setting that allows 640w resolutions? Are you encoding to iPod with Compressor as well? And have you tried converting the DPX files to 8bit instead of 10bit?



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ikarus79m
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 5, 2006 at 10:44:18 am

Yes it's the new setting. It's the same result with the old setting though, besides that it's smaller. I did both H.264 encodings in compressor. One with the Quicktime 7 preset, the other one with the IPod preset. I just don't get it!

Also, if I play Quicktime 7 preset H.264 file in lets say Firefox insteas of Quicktime or Safari it play normal. I just don't understand what's going on here.

I also tired exporting to an 8-bit codec with the same result.



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ikarus79m
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 5, 2006 at 11:42:45 am

Also, apple seems to have issues with this themselves. Check out the HD Eragon Trailer ( http://www.apple.com/trailers/fox/eragon/hd/ ) in Quicktime, it's got deep rich blacks, everything is ok there. Now check out The Perfume HD ( http://www.apple.com/trailers/dreamworks/perfume/hd/ ) trailer in Quicktime: Black's aren't 100% black. Now open that same trailer with Firefox on your mac and...voila...it's got deep rich black... WTF? What is this?



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Charles Simonson
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 5, 2006 at 4:08:07 pm

Hmmm. The gamma issue has been around for quite some time so this is not surprising to hear. I was hoping it was a conversion issue from 10bit to 8bit when Compressor was encoding, but I guess not. A couple of other things to try are to test an export from an Animation codec and None codec source. The only thing I can think of is that it is likely a profile issue with the H264 decoder. For the iPod, it is using the baseline profile, but for your other encodes it uses the main profile. I wonder if you were to download Episode from Flip4Mac and encode with similar settings if the issue were there as well?



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ikarus79m
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 6, 2006 at 1:07:29 am

I will try the animation codec later, but I doubt that will help. Episode Pro isn't really any help to me either since i tcan't deal with PSD or TIFF image sequence quicktimes. If I try to encode my Blackmagic 10bit or 8bit files with Episode Pro I get an equal bad gamma shift.

Playing some more with compressor I found out that if I apply a gamma value of 1.2 in the filter settings that I get a resulting image very similar to the input. Of course I am afraid that it might look to dark when played back with anything else but the quicktime player. If I play that vide with Firefefox for example it is too dark.

As I mentioned before the same problem seems to be affecting some of the trailers on the apple website. Here some screenshots:

Here is a screenshot from the Perfume playing in Quicktime:

Image Hosted by ImageShack.us
?
Here is that same shot playing in Firefox:

Image Hosted by ImageShack.us
?

The Eragon Trailer, however, looks fine fine in Quicktime:

?Image Hosted by ImageShack.us

But is too dark in firefox:

?Image Hosted by ImageShack.us

Do you have any idea what's going on here?



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duffbeer911
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 7, 2006 at 4:24:46 am

I read an article online not so long ago about quicktime7 not reading the colour space correctly in h.264 and that is why it looks ok when you get a different application to play it .... I can't remember where I read it so it may just be rubbish.....


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caseyfilms
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 8, 2006 at 10:38:08 pm

if you can, try exporting from after effects uncompressed or whatever your native format is, then directly compress with quicktime or better yet final cut. i found the h.264 compressor compressions to always be crapass. i have gamma shift issues, but with 3d applications it also creates a ton of aliasing for some reason.

however, when exporting directly from FCP both of these issues disappear and it's as it is supposed to be.

good luck


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benloveridge
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Jun 25, 2007 at 11:43:04 am

This is what I did to work around this problem exporting from Final Cut Pro via compressor to make H264 clips from HDV footage. Export sequence using Quicktime conversion from FCP, format is Quicktime movie, video settings remaining on HDV as per the sequence, 'auto' data rate. Select 'options', 'filter', 'adjustments', source profile set to Adobe RGB, destination profile set to sRGB IEC6966, matching option left on 'perceptual'. I then imported the clip into compressor and used the HD-DVD setting to make the H264 clip. I used to have the same problem with photoshop and getting washed out colour shifts when exporting pictures for the internet. The same kind of colour space conversion seems to have done the trick for me in video land.



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Attila Kovarcsik
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Aug 6, 2009 at 9:14:52 am

Did you guys solve this problem? I have the same. I exported out a final cut movie and in Quick Time it looks ok, if I turn on the final cut function in the settings. Ok, but in VLC or other apps it is still brighter. What should I do?


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Steve Thomson
Re: Compressor H.264 MADNESS! (Gamma shift?) - Pictures Included.
on Nov 11, 2010 at 2:00:42 am

This is a frustrating issue. I have had a similar issue rendering prores out of AE. This one is solvable by making sure that you dig into the prores output module and turn gamma correction to none. I would like to think that there is a similar setting within the H264 codec settings within compressor to do the same thing but I cannot find. Anyone got any other ideas?

cheers,

Steve Thomson
http://www.brandspank.com
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