Any loss of quality in conversion?? at DVinfo.net

Brent Marks · March 16th, 2005, 12:49 PM

When you conver the m2t files to .avi in Cineform.... to make them easier/faster to edit...

Is there any loss of quality in that?

Or when you render down to mpeg2

?

THANKS!

David Newman · March 16th, 2005, 02:15 PM

We have the quality analysis on the CineForm website that shows up to nine generations that explains all of this. http://www.cineform.com/technology/quality.htm Mathematically there is loss with any quantizing compression, the trick to minimize that loss so that it can't be seen. All codecs do this with varying degrees of success. CineForm uses a wavelet compressor so generally it will achieve higher quality at low bit-rates than other DCT based digital intermediate compressors like Canopus HQ, Avid DNxHD, and Apple AIC. Generational losses also depend on your workflow 8bit vs 10bit, RGB vs YUV. Aspect HD and Connect HD use a 8bit RGB workflow to match that of the Premiere and Vegas standard rendering engines. As 99% of all compressed video is YUV (DV, HDV, MPEG, JPEG etc) so RGB workflows result in additional loss. Prospect HD uses a 10bit YUV workflow, replacing much of Premiere's rendering engine for greater multi-generation characteristics. CineForm is always interested increasing quality (eventually all the way to mathematically lossless) so we are always interesting in receiving demanding footage so we can tweak the codec. We have done this in the past.

Brent Marks · March 16th, 2005, 02:56 PM

Thanks David...

You've given me exactly what I needed/wanted!

U rock,
Brent

March 16th, 2005, 12:49 PM	#1
Brent Marks Major Player Join Date: Jan 2005 Location: Houston TX and New Orleans LA Posts: 300	Any loss of quality in conversion?? When you conver the m2t files to .avi in Cineform.... to make them easier/faster to edit... Is there any loss of quality in that? Or when you render down to mpeg2 ? THANKS!

March 16th, 2005, 02:15 PM	#2
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	We have the quality analysis on the CineForm website that shows up to nine generations that explains all of this. http://www.cineform.com/technology/quality.htm Mathematically there is loss with any quantizing compression, the trick to minimize that loss so that it can't be seen. All codecs do this with varying degrees of success. CineForm uses a wavelet compressor so generally it will achieve higher quality at low bit-rates than other DCT based digital intermediate compressors like Canopus HQ, Avid DNxHD, and Apple AIC. Generational losses also depend on your workflow 8bit vs 10bit, RGB vs YUV. Aspect HD and Connect HD use a 8bit RGB workflow to match that of the Premiere and Vegas standard rendering engines. As 99% of all compressed video is YUV (DV, HDV, MPEG, JPEG etc) so RGB workflows result in additional loss. Prospect HD uses a 10bit YUV workflow, replacing much of Premiere's rendering engine for greater multi-generation characteristics. CineForm is always interested increasing quality (eventually all the way to mathematically lossless) so we are always interesting in receiving demanding footage so we can tweak the codec. We have done this in the past. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

March 16th, 2005, 02:56 PM	#3
Brent Marks Major Player Join Date: Jan 2005 Location: Houston TX and New Orleans LA Posts: 300	Thanks David... You've given me exactly what I needed/wanted! U rock, Brent