video compression

[lefty]

can anybody explain how the video files
on the quictime hompage are so small(11 megs) considering that the frame size is huge and image and sound are amazing. I have recently posted a video which was compressed using cleaner 5 - its about 7 min @ 320 by 240 and is still 40 megs

[GG]

Unless I'm mistaken looks like MPEG-4
Very long GOP. i.e. very few I frames.

My old PC has trouble keeping the sound in sync with the vision, only syncs up at every cut, where the I frames are.

Post a link, to check we are looking at the same things.

[lefty]

here's one @ 21 megs
http://www.apple.com/trailers/sony_pictures/hellboy/hellboy_trailer_high.html

[PaulD]

Hi
The movie trailer in your link is made with the Sorenson 3 codec, 2-pass VBR, average data rate 133KBytes/sec, 24fps, 480x260pixels. This gives a file size of 19.3MB for 2' 28".

This will have been encoded in Cleaner, using the Pro Version of Sorenson 3. Because of the 2-pass VBR control that this combination gives it is still better than MPEG-4, until a good 2-pass VBR utility for that emerges.

Sorenson 3 Pro gives good results at down to below 60KB/s for slightly smaller pixel dimensions.

The regular Sorenson or MPEG-4 codecs will give useable results if used with care. If you encode with QuickTime Player Pro's Default setting for Export (the drop down menu at the bottom of the Export Dialogue Box) then you will get better results than you hitherto have.

The Defaults for QT6 are MPEG-4, and Sorenson for QT5.
Regards

[This message has been edited by PaulD (edited 10 December 2003).]