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Zookoo
04-10-2009, 02:25 PM
Hi guys,

After searching the forums, I couldn't find an answer to my problem. I'm sure it has been covered before, but many threads I found have closed down due to inactivity :(

My problem is that whenever I compress a high res video in Quicktime Pro or Sorenson Squeeze, the video always end up looking really bright and desaturated.


For example, I had a video originally at 383Mb then I used these settings in Quicktime Pro to compress it to about 1Mb as a .mov file:

Compression: H.264
Quality:High
Bitrate: 1000kbits/sec
Frame recording: yes
Encoding mode: multi-pass
Dimensions: 924x520 (Current)

Alot of people on the forum say they had positive results when they use the H.264 codec. So I'm just not sure what I'm doing wrong.
I've tried other codecs, but they all seem to give the same washed-out look too except for Animation, Jpeg 2000, None, and PNG. But the video size using those 4 compression types are way too huge for internet streaming.

I've tried using Sorenson 3 on Sorenson Squeeze but I had the same result :(

Any ideas would be much appreciated!!

LordSaddler
04-11-2009, 02:28 PM
Sounds like the Quicktime Gamma-Shift. The video itself is encoded fine, but the Quicktime Player adds a small tag, that raises the gamma during playback leading to a washed out / grey image.

There is a hack for it (removing the tag), but i donīt have it in mind (probably just google quicktime gamma tag). Other Players like VLC should play the movies correct btw.

Zookoo
04-11-2009, 09:35 PM
Lordsaddler: Thanks for your reply! I appreciate the help and have learnt about the tags after doing some research. But the ones I could find have not worked unfortunately. Even the common ones alot of forums/blogs suggested :(


After hours of searching for solutions on the net, I've come to understand that this issue has been around for quite a while. It seems no one really has a definite answer to it and I've read threads that would go on for pages but never conclude with anything that really works. It worries me that some people have said they've been looking for an answer to the issue for months or even years. I'm not sure why its so hard to fix this problem if its so common.
I'm just really curious to know how apple trailers and some demo reels get to look so good in whichever player its on. I just hope apple fixes quicktime soon :(

The best result I could get was following this site. Afew other people have also pointed this process:
http://www.praisepictures.com/h264_gamma.php

Instructions are pretty much this:

"Choose Window > Show Movie Properties or CTRL+J. This opens the Movie Properties window.
Highlight the Video Track and choose the Visual Settings tab below.

There is a Transparency drop down on the lower left. Change the option to Blend. Now if you take a look at your video you should see it looks like a white solid has been placed over it. Drag the bar under Blend to 100.

Now change the Transparency mode to Straight Alpha. Click your video and hit your arrow keys to advance to the next frame.
Now all you have to do is go to File > Save to make sure that whenever this file is opened whether its your computer, or someone elses, that its read with the proper settings."

It has adjusted the gamma for my compressed video, but it leaves my video looking more pixelated than before. Looks fine for bright videos but videos with dark shots would be noticable. I'll use this for now until I find a better solution :P

If anyone have any other ideas around these, please mention it! :D

Thanks:)

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04-11-2009, 09:35 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.