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h.264 gamma shift or limited range levels ... again

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Ron Fya
h.264 gamma shift or limited range levels ... again
on Feb 8, 2012 at 7:23:43 pm

Hi there,

First of all, sorry the length, but I don't see how I can explain this huge problem in a shorter way.
I know I am not alone out here having troubles with h.264, gamma, and all the players around that make all your beautiful colors and tones look different.
I am not talking here about the fact that the video looks different on different computers. That is unavoidable, we have to deal with it and that's why we calibrate our system. But on one given computer, how the hell is it that a given video can look sooo different depending on which software you use to view it ?

I have a good grasp of color management for photos, but I am completely lost for videos, and I am sure we will be a quite a few here if some pros can answer the following.

I made screen caps from a H.264 video from a Canon 7D.

First row are what the video looks like in the Final Cut Pro X monitor and Premiere CS5.5
Last column is the video straight out of cam viewed in VLC, MPlayer, Quicktime X and Quicktime 7
Others are exports from FCPX and Premiere with the defaults H.264 settings and viewed in the same players.

After a close comparison of the screen caps, switching on/off one over another, I grouped the matches in color groups to describe the problem :
Green, yellow and red groups are nearly perfect match within groups. (and in the case of greens, it is probably 100% perfect because it's apple QT)
A rough classification from dark and saturated to bright and desaturated would be : RED, BLUE, YELLOW, GREEN, PINK.
[BLUE & YELLOW] are different but very close, [GREEN & PINK] as well. I can live with that. No problem.

But RED is very different from [BLUE & YELLOW] which are both very different from [GREEN & PINK]
The strangest thing for me being the export from Premiere which displays differently in QT7 and QTX.
Does somebody have an explanation for this or even better, a fix ?

- I already tried the "fix" with the transparency layer in QT pro but it does not work at all
- I heard about x264 but Adobe Media Encoder refuses to work when using it and does not change anything when exporting through Compressor
- I heard about the limited range of colors (16-235) of the Rec.709 HD standard
That limited range is also causing VLC to wash out colors on PC with nVidia graphic cards
I am on a MacBook Pro, OSX Lion with nVidia GeForce GT 330M but there is no control panel for it.
Maybe something to fix in my workflow in that regard ?

How do the big studios like Dreamworks do to export consistent material ?

What are your favorite codec and container for exporting high quality to web apart h.264 / mp4?

What are your favorite codec and container for burning DVDs ?

Can anyone provide a link to a comprehensive and accurate real world RECIPE BOOK for encoding/exporting ?
I mean, I am in urgent need of finding a way to export PROPERLY for web and DVDs before even taking the time to understand everything.

Thank you so much everybody !


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Scott Firestone
Re: h.264 gamma shift or limited range levels ... again
on Mar 10, 2012 at 5:21:11 pm

1. Yea, the situation is even worse than you think. Google QuickTime Gamma Vitrolite. It will lead you down a rabbit hole. the situation with VLC is even more complicated: it depends on which VLC output module you select. Total Insanity.

2. Film studios use RV player from Tweak Software. The player can only play back image sequences, not movie files, but it does so perfectly in every way. It's $300.

3. Check out Kert Gartner's blog. He just went through an exhaustive process of trying to figure out how to get the most optimized H.264 video output, experimenting with various software, codecs, image tweaking, gamma tweaking, etc. I was hoping he would find a fix to the problem, but, nope: He concludes that there's no way to achieve good quality for compressed H.264 video, when playing the file on a PC in the QuickTime player, due to the way that QuickTime washes out the video. He has a pretty good workflow for maintaining high quality video: His process, in a nutshell: He encodes a high quality master version using the QuickTime "JPEG-photo" codec, with quality set to 99%: it looks as good as lossless, but has a smaller file size. Then, when he creates a version to upload to YouTube or Vimeo, he compresses using the QuickTime H.264 encoder at maximum quality, then uploads it. With this workflow, it's important that people watch the video in the browser, and not in the QuickTime player on a PC.

4. for the codec/container for burning DVDs: I try not to use any type of intermediate container. I render still image sequences out of my 3D program (TIF), then assembly my video in After Effects: Then I go into Premier, and dynamically link to the After Effects Project. That way, Premier grabs an uncompressed render directly from After Effects, without using an intermediate container. Then use Premier to encode directly into the MPEG format needed by the DVD. Import that MPEG file into Encore, and Encore will not have to do any re-encoding.

5. You're in luck if you only intend to have people watch the video on the web and DVD: You can generally avoid the contrast adjustment that incorrectly converts video to rec.601: that's what happens when you play an H.264 video in the stand-alone QuickTime player on a PC. If you are on a PC, drag-and-drop an H.264 mov file into Firefox: it plays correctly. Open that same file in the Stand Alone QuickTime player on a PC, and it looks washed out.

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