Png & jpeg2000

Lumiere

Lumiere

Well-known member
I was trying and comparing the results of codecs and comprations on media encoder cs4, and i realize that JPEG2000 codec give awesome results, then i tried out the same footage with PNG codec, it almost exported 5 times longer.Even with jpeg2000 codec it cannot play smootly on the desktop, but didn't try on premiere. On wikipedia it says PNG codec is lossless,does you guys use one of these codec for any reason?

PS:my exports was QT...
 
PNG is a lossless compressed bitmap. It does nothing to throw away information to create a picture. It will retain up to 16 bits of color per channel of the original image.

JPEG2000 can perform lossless compression but, I don't think it's implemented in Quicktime's codecs. Jpeg2000 is a wavelet compression, which means that data is thrown away to decrease file size.

Jpeg2000 at 75 quality does a good job of being "visually lossless" while maintaining a good file size.

On the PC, the JPEG2000 codec is not fast enough for real-time playback of any broadcast sized frame sizes.

PNG files will be so large when compressing video signals that you will need a powerful raid (70+Megabytes per second) just to play back the video in real time.

PNG's compression algorithm is good for graphics, where there are blocks of the same color in large areas. (Think of powerpoint slides)

JPEG2000's compression algorithm is good for photos, since it only throws away data that can't be seen well by the human eye.


See these pages for further reading:

http://en.wikipedia.org/wiki/JPEG_2000

http://en.wikipedia.org/wiki/Portable_Network_Graphics

Both codecs aren't really good for anything other than a high quality master version that you store away and re-code as needed.
 
Allright i get it, thanks a lot Demistate, How does people send their files to other editors or clients.Lets say may customer wants to see very high quality example of the editing we are in..Or just say you want to back up your files for the potencial touch in the future..?

Thanks
 
Lumiere said:
Allright i get it, thanks a lot Demistate, How does people send their files to other editors or clients.Lets say may customer wants to see very high quality example of the editing we are in..Or just say you want to back up your files for the potencial touch in the future..?

Thanks
Click to expand...

You can usually embed an h.264 into a web page via flash 10 when asking clients to view it. (Don't assume they know how to use comptuers, so don't make them download anything.) It should be as easy as clicking a link. It may be better to use ON2 VP6 instead of h.264 since clients may not be able to upgrade their version of flash on access-restricted work comptuers.

As for sending to another editor, try sending the same source files if possible. Always ask your editor on the other end how they work, and try to output files that match their workflow.

As for backup, Source file backup is always the best, unless you go through some crazy post up-sampling process.


Read my other thread for more information : http://www.dvxuser.com/V6/showthread.php?t=137018
 
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