Using cineform hdv to capture - Page 2 at DVinfo.net

Go Back   DV Info Net > Cross-Platform Post Production Solutions > CineForm Software Showcase

CineForm Software Showcase
Cross platform digital intermediates for independent filmmakers.


Reply
 
Thread Tools Search this Thread
Old April 4th, 2005, 02:27 PM   #16
Trustee
 
Join Date: Aug 2003
Location: Vancouver BC Canada
Posts: 1,315
As I understand it the High Frequency is the part of the image that deals with edges which give the detail. Is this true? If so then that might be why the blue-screen problems.
Does this capture mode have any effect on CC ability? Would it help the image not fall apart so fast?
__________________
Damnit Jim, I'm a film maker not a sysytems tech.
Ken Hodson is offline   Reply With Quote
Old April 4th, 2005, 02:53 PM   #17
CTO, CineForm Inc.
 
Join Date: Jul 2003
Location: Cardiff-by-the-Sea, California
Posts: 8,090
Yes detail is carried by high frequency information. That is always compressed in video system based on the human visual model. We can see low frequency quantization easier than high frequency quantization. This is how all human modelled compression works from DV to MP3. A visually lossless compression can reduce the bit-rate by compressing the elements you cannot see. Uncompressed HD is around 100MBytes/s, CineForm compression is around 12-14MBytes/s -- it looks the same, but of course mathematically it isn't. There are plenty of books on this subject -- just type "video compression" into the search field on Amazon.com.

Blue-screening is a little more difficult for any compression system as it does not follow human visual models -- it is not the human eye that is doing the key, it is some third party mathematically model. So this very much depends on the logic of the key. Use a good keyer on a compressed source and it will work great (rememeber most sources are compressed in some form.) We re-did some tests after this thread and found chroma-keying of our sources works fine on a good keyer. We have many customers using CineForm compression of compositing work. Unfortunately I haven't yet received sample data from this particular customer to see if anything can be done to improve the situation (I hope that happens.) As you quoted, we have a mathematically lossless transform, so we can adjust to store any sequence.

> Does this capture mode have any effect on CC ability?

CC = Color Correction? Yes the codec is very good at color correction and preserving the quality over generations. Using "Large" capture mode versus medium has not much impact on color correction.

> Would it help the image not fall apart so fast?

The whole point of CineForm compression is to greatly reduce multi-generational losses. You can see this analysed here : http://www.cineform.com/technology/quality.htm
__________________
David Newman -- web: www.gopro.com
blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman
David Newman is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Cross-Platform Post Production Solutions > CineForm Software Showcase

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 10:28 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network