M2t question and Gearshift

epirb wrote on 6/29/2005, 4:50 PM

first let me say that this method might be a little convoluted, but bear with me.
I had a HDV tape that I captured with Cineform.
then I used Gearshift to create a dv widescreen proxy.
I then put the proxy on the timeline and created regions of clips I wanted to keep.
Used Gearshift to replace with the orig M2t file.
Used Excalibur to render regions to files using the regions as file names.(rendering to the mainconcept HDV 60i, m2t files)

I am doing this because there is much on this tape that I dont want.Plus I want to save these "sections" of the original long m2t file , as separate clips to use in this and future projects.(giving them each a descriptive name)

My question is this; is it normal when rendering for the native m2t file with NO Fx on both audio and video side to take longer than real time to render? ie 25 second clip takes 1min 30 sec.'s. And Is there any quality loss rerendering the org m2t clip to another m2t. Again no effects just raw footage trimed down.

I cant think of any other way to do this , to have trimmed copies of the original m2t file with separate names for each trimmed portion, in batch . The only other way I can think of is to preview all and capture 1 by 1 files from the camera, but not having batch capture with HDV this is the only way I can think of.

Any input welcome, but I really want to know if I am suffering a quality loss rendering the m2t section to a new m2t file.

Comments

epirb wrote on 6/29/2005, 8:44 PM

another question is..
if you created a GS proxy in one project can you use it in another and "shift gears" to the real media in any other project you use the proxy in? in other words ,does that proxy file contain info t o refer it back to the original m2t file always? so I can retain the proxies for future use, as long as the two files stay in there original locations?

Spot|DSE wrote on 6/29/2005, 9:05 PM

The proxies will refer back to the original folder, so you'll need to have the m2t in the same folder as the DV proxies, or have the CineForm files in the same folder as the DV proxies. You'll always be fine w/that.

Spot|DSE wrote on 6/29/2005, 9:09 PM

There is loss in rendering m2t to m2t. We have a workaround for this, but won't have it released for another few days. (Free upgrade for existing users of GearShift)
http://www.cineform.com/technology/HDVQualityAnalysis/HDVQualityAnalysis.htm has images of m2t to m2t at various recompression stages.

Wolfgang S. wrote on 6/29/2005, 11:10 PM

Douglas, that link looks fine.

However, it compares all with an uncompressed format. In reality most of us will start from m2t.

So, what is missing in that link is the comparison

m2t (captured) (A) --> m2t (1st generation) (B) (as result of an workflow based on proxys in Gearshift)

versus

m2t (captured) (A) --> Cineform (1st generation) (C) --> m2t (2nd generation) (D) (as result of a workflow where we apply Intermediates, and render out to m2t).

So, I think it would be necessary to see comparisons

(A) vs (B)
(A) vs (C)
(A) vs (D)
(C) vs (D)

to know the complete story.

epirb wrote on 6/30/2005, 3:58 AM

Thanks Spot and Wolfgang,
I guess my best bet is to single out the good clips on the tape and only capture those as individual m2t files, then use Gearshift on those, if I want to keep the quality high and archive the individual clips. This will be for DVD and poss .wmv 720p output as of now ,but as we know, in the future........

I cant wait to see whats coming in the next few days, sounds very interesting.