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LC1104
4th June 2002, 10:32
This may be a dumb question, but I have been trying to transcode an MPEG-2 clip which is 30 fps to Quicktime AVID OMF format in 24 fps. I am currently using Cleaner 5.1.1 (I hate this buggy program but I don't know what else has this capability). The problem that I have is that the final OMF clip comes out jerky and stutters often - I realize this is becuase I am going from 30 to 24 fps. I have inverse telecine enabled. Any advice on how to do this better?

I am working on a Dell Precision:
dual P3 1Ghz
512 MB Ram
Matrox G450
20GB system; 500GB Videoraid SCSI

Thanks so much for your help guys.

-jason

dZeus
4th June 2002, 13:12
if (parts of) the source has been shot on video or edited on video during the process of mastering/etc it, then ivtc will always be 'imperfect', as you will see stutter during panning which weren't there in the original, even when you play back the 24-fps-ivtc-ed result with 3:2 pulldown.

Maybe this is the cause in your case?

Sciascia
5th June 2002, 01:11
TMPGEnc has a pretty good inverse telecine tool as well as DVD2avi.

I was under the impression that OMF files were only able to be created on AVID systems, using their HW for compression. I assume that you are using a SW codec for it (let me know if I am right /wrong here), just wondering how good it is? This would be very helpful for converting and transferring files from AVID Media Composers, the Newscutters to the AVID Airplays.

LC1104
5th June 2002, 12:08
I am using a Quicktime codec that enables Avid OMF compression. So the output files are .mov files but encoded with the avid mjpeg schematic. I am using Windows 2000 and Cleaner 5.1.1 to do this. The one problem with this though is that these files play at half the frame rate - I don't know if this is a Windows 2000 problem (as many videos play horribly with a lot of stuttering on the 2000 system but then play fine on the XP system that I have).

Off this topic, I have another question. Does anyone know where I can get a very good source clip that is uncompressed, 720x480? I tried just capturing from my WinTV card but the noise makes the picture so unclear. My next best option would be to rip a DVD. My goal is to now encode to MPEG-2 (I realize if I went the DVD route, it would be reencoding MPEG-2) with two different settings, 4:2:2 and 4:2:0 and compare the difference. If I do choose to use a DVD clip as a source, should I rip it, say using smart ripper or would it be better to capture it through s-video. If you do have a good uncompressed source you can send me - it only has to be a few seconds long at the most - I would be very grateful.

jason