Question for folks shooting 24p w/HV20 or HV30 at DVinfo.net

Robert M Wright · January 7th, 2010, 06:06 PM

I'm considering collaborating with my brother, to write a software app that would automate proper removal of pulldown from 24p footage recorded by the HV20 or HV30 and captured as m2t files (making it a very simple task to perform).

Is this something that would be valuable to you? Would it be worth spending something like $30-$50 for?

Robert M Wright · January 7th, 2010, 06:28 PM

The conceptual approach, as yet untested, should make it possible to yield a conversion with absolutely no image quality degradation from re-compression.

Ray Bell · January 7th, 2010, 09:09 PM

Its called Cineform and it cost around $100.... someone beat you to it...

Joel Peregrine · January 7th, 2010, 09:49 PM

No image degradation at all? That would be great.

On an Apple I do this process with a Compressor droplet and have also done tests with JES Deinterlacer. Both degrade the image but JES produces a better result, but because of JES's clunky interface I use Compressor more often.

The comparison shot is Compressor on the left and JES on the right at 400%. You can see how chunky the Compressor conversion is compared to JES. Both are noticeably softer than the original. (The next time I need to do this process I'll grab stills of the original too.)

http://www.dvinfo.net/forum/attachme...1&d=1262922438

Robert M Wright · January 8th, 2010, 12:06 AM

Quote:

Originally Posted by Ray Bell

Its called Cineform and it cost around $100.... someone beat you to it...

Cineform can remove the pulldown*, but you are limited to output being encoded as an AVI (Windows) with Cineform's codec (unless something changed recently). What I'm talking about is removing pulldown without any image quality degradation, and output being an MPEG-2 encoded video stream (in an MPEG transport stream container - an mts file, just like the captured source file), which is much smaller than a Cineform encoded file (and Cineform's encoding uses a lossy compression scheme, although the result is generally accepted as being visually lossless). Also, Cineform costs more than twice as much as what I would expect to price our product at, should we proceed to develop it.

*I'm not sure if Cineform's pulldown removal is always done correctly though. There are no pulldown sequence flags encoded in the 24p recordings produced by the HV20 or HV30, so detection of the proper sequence is not entirely straight forward.

Robert M Wright · January 8th, 2010, 12:32 AM

Obviously, a tool, like the one we are considering developing, would be of little use to folks who capture with Cineform's product, directly to a file encoded with Cineform's codec, using that for editing (or whatever), while having no use for a file on their computer containing the original source.

Where it could be potentially quite useful, is for folks who want to drop HV20/HV30 24p source footage directly on their NLE's timeline for editing (editing HDV natively) or for archiving the original source footage, but with pulldown removed (once and for all - no need to ever do it again at some point in the future).

Joel Peregrine · January 8th, 2010, 12:50 AM

Would it be similar to a "re-wrapping" like clipwrap?

ClipWrap

Robert M Wright · January 8th, 2010, 01:07 AM

Sorry, I'm not familiar with clipwrap. Is that Mac software? (I've barely even touched a Mac in over 2 decades now.)

Robert M Wright · January 8th, 2010, 01:25 AM

Another way to look at it is, we are essentially considering creating a utility to convert the 24p footage (encoded into a 60i HDV standard compliant stream) from an HV20/HV30 into what you get from an XH-A1 when shooting 24F, as a practical matter, except 4:2:0 chroma sampling would still be the same as with interlaced material. (To convert the chroma sampling into the same 4:2:0 sampling as used with 24F progressive encoding, would necessitate image quality degradation from both conversion and from re-compression, with no actual benefit realized.)

Joel Peregrine · January 8th, 2010, 02:46 AM

Quote:

Originally Posted by Robert M Wright

Sorry, I'm not familiar with clipwrap. Is that Mac software?

Yes.

Clipwrap.com:
Easily rewrap m2t, mts, and m2ts files into QuickTime movies
Faster than transcoding
No generation loss

So this will be Windows only?

Ulises Rodriguez Pomba · January 8th, 2010, 09:10 AM

Currently nobody whants to transcode...

The really ussefull app is one capable of writing in-situ M2T files the pulldown flags that they are missing (detecting it on each file). So this make possible to a ENG to automaticaly interpret the file i guess...
or reinterpreting at 24PulldownAdvanced...

No transcoding, no HD space, no color conversions, no more codecs = NATIVE

Robert M Wright · January 8th, 2010, 12:20 PM

There's a number of ways to go about pulldown removal with 24p footage from the HV20/HV30 (both before and after editing). (Personally, I currently use VirtualDub.) I don't know of any utility that will do it entirely automatically (and also reliably get it right) and simply (in essence) convert the source footage to what amounts to the natively progressive 24F MPEG-2 you get out of an XH-A1, not transcoding with some other codec, and without degrading image quality (and not altering audio either).

January 7th, 2010, 06:06 PM	#1
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Question for folks shooting 24p w/HV20 or HV30 I'm considering collaborating with my brother, to write a software app that would automate proper removal of pulldown from 24p footage recorded by the HV20 or HV30 and captured as m2t files (making it a very simple task to perform). Is this something that would be valuable to you? Would it be worth spending something like $30-$50 for?

January 7th, 2010, 09:49 PM	#4
Joel Peregrine Major Player Join Date: Oct 2002 Location: Wisconsin Posts: 689	No image degradation at all? That would be great. On an Apple I do this process with a Compressor droplet and have also done tests with JES Deinterlacer. Both degrade the image but JES produces a better result, but because of JES's clunky interface I use Compressor more often. The comparison shot is Compressor on the left and JES on the right at 400%. You can see how chunky the Compressor conversion is compared to JES. Both are noticeably softer than the original. (The next time I need to do this process I'll grab stills of the original too.) http://www.dvinfo.net/forum/attachme...1&d=1262922438 Attached Thumbnails __________________ WeddingFilms.com>>

January 8th, 2010, 12:50 AM	#7
Joel Peregrine Major Player Join Date: Oct 2002 Location: Wisconsin Posts: 689	Would it be similar to a "re-wrapping" like clipwrap? ClipWrap __________________ WeddingFilms.com>>

January 7th, 2010, 06:28 PM	#2
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	The conceptual approach, as yet untested, should make it possible to yield a conversion with absolutely no image quality degradation from re-compression.

January 7th, 2010, 09:09 PM	#3
Ray Bell Regular Crew Join Date: Nov 2004 Posts: 1,414	Its called Cineform and it cost around $100.... someone beat you to it...

January 8th, 2010, 12:32 AM	#6
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Obviously, a tool, like the one we are considering developing, would be of little use to folks who capture with Cineform's product, directly to a file encoded with Cineform's codec, using that for editing (or whatever), while having no use for a file on their computer containing the original source. Where it could be potentially quite useful, is for folks who want to drop HV20/HV30 24p source footage directly on their NLE's timeline for editing (editing HDV natively) or for archiving the original source footage, but with pulldown removed (once and for all - no need to ever do it again at some point in the future).

January 8th, 2010, 01:07 AM	#8
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Sorry, I'm not familiar with clipwrap. Is that Mac software? (I've barely even touched a Mac in over 2 decades now.)

January 8th, 2010, 01:25 AM	#9
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Another way to look at it is, we are essentially considering creating a utility to convert the 24p footage (encoded into a 60i HDV standard compliant stream) from an HV20/HV30 into what you get from an XH-A1 when shooting 24F, as a practical matter, except 4:2:0 chroma sampling would still be the same as with interlaced material. (To convert the chroma sampling into the same 4:2:0 sampling as used with 24F progressive encoding, would necessitate image quality degradation from both conversion and from re-compression, with no actual benefit realized.)

January 8th, 2010, 09:10 AM	#11
Ulises Rodriguez Pomba New Boot Join Date: Jun 2008 Location: Cordoba, Argentina Posts: 5	Currently nobody whants to transcode... The really ussefull app is one capable of writing in-situ M2T files the pulldown flags that they are missing (detecting it on each file). So this make possible to a ENG to automaticaly interpret the file i guess... or reinterpreting at 24PulldownAdvanced... No transcoding, no HD space, no color conversions, no more codecs = NATIVE

January 8th, 2010, 12:20 PM	#12
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	There's a number of ways to go about pulldown removal with 24p footage from the HV20/HV30 (both before and after editing). (Personally, I currently use VirtualDub.) I don't know of any utility that will do it entirely automatically (and also reliably get it right) and simply (in essence) convert the source footage to what amounts to the natively progressive 24F MPEG-2 you get out of an XH-A1, not transcoding with some other codec, and without degrading image quality (and not altering audio either).