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David Goldschmidt
I am missing something
on Dec 29, 2007 at 3:22:09 pm

Hey guys. I want to explain my situation and PLEASE PLEASE if someone can help me that would be great.

I have a new laptop. XPS M1730
Sorenson Squeeze
a program called Mediashout (its a program many churches use to display song lyrics and video through a projector)
Digital Juicers

In the past (before Sorenson) I exported my Digital Juice Jumpbacks as quicktime files. Then i imported all my quicktime files and exported them out of Adobe After Effects as Mpegs. This was 2 years ago and I had no better knowledge about the topic of compression and AE did it all over night.

Anyways, the more I got into video the less happy I was with the MPEG quality of my digital juice jump backs. I want them to be super high standard def quality at small file size.

So I took my full res quicktime movies and dropped them into Sorenson. I want to export them as MPeg 2 DVD quality. But everytime I change settings, do this do that, I get POOR results. I actually get better results exporting out from Premiere.

Example: My blacks turn almost grey and whites are washed out. Now I dont know if this is my laptop screen issue or something else, but my original quicktime files is BLACK AS BLACK can be..

Also, its all pixelated when i export a fireworks video you can see the color degragation. And lastly the audio doesnt export out of sorenson.

Can someone PLEASE PLEASE PLEASE help me figure out what the HECK i am doing wrong with Sorenson. I thought I was going to get better results even with the presets. i know they are limited. Thanks in advance

Sorry for the long description but I wanted to make it as clear as possible.

By the way. I also get really black color exporting as an Mp4. unfortunatly the Mediashout which is my end broadcast doesnt support Mp4 yet.

Also, my end resolution should be 1024 x 768.

http://www.overflowuk.com


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Aharon Rabinowitz
Re: I am missing something
on Dec 31, 2007 at 2:50:27 am

OK with reagrd to adio - make sure your original video has audio. There is no reason for squeeze not to have audio unless there is no source audio that it can read or...

The audio checkbox is unchecked in the compression settings.

To increase the quality, increase the data rate. You may also want to increase the number of video keyframes.

AS far as the black is concerned, I'm not sure what to tell you. Is WMV an option? WMV preserves color pretty well.



Aharon Rabinowitz
Email: arabinowitz (AT) yahoo (DOT) com
All Bets Are Off Productions, Inc.
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Daniel Low
Re: I am missing something
on Jan 2, 2008 at 10:17:42 am

MPEG-2 will display blacks as grey on a PC monitor, but on a TV they should look black. PC's (which use RGB) can display 0-255 grey values, a broadcast format like MPEG-2 is limited to 16-235. Quicktime codecs like MPEG-4 will behave differently, as you have found.
MPEG-2 conforms to CCIR 601 - more here - http://en.wikipedia.org/wiki/CCIR_601
http://en.wikipedia.org/wiki/RGB_color_model

Increasing datarate may not necessarly increase quality, try using 2-pass and/or VBR.

The same can be said of keyframes - increasing the number of keyframes can actually hurt the quality, besides, MPEG-2 does not use keyframes but rather GOPs - Groups Of Pictures.

You may want to look at a more professional transcoding package than Squeeze, have a look a Procoder from Grass Valley, it will most certainly give you better quality output.


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David Goldschmidt
Re: I am missing something
on Jan 2, 2008 at 11:29:23 am

Ok, i am understanding a bit more thanks. I do have a high quality bright Laptop and thats my main issue. Now i have to figure out why Sorenson is creating an extra frame in my video. It should loop seemlessly but its not, there is a blank frame that isnt there in my original. Thanks

http://www.overflowuk.com


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