Flash Frames and HD->SD problems in FCP at DVinfo.net

Derek Prestegard · March 27th, 2007, 01:49 AM

Hey everyone,

So I'm consulting for a project, and I am witnessing some very strange behavior. The basics - Final Cut Pro 5.1, source material is a mixture of HD (all in Photo JPEG, which is the project codec at 23.976), and 24p DV (simple 3:2 pulldown) which is a low resolution version of super 16 film that will later be onlined to HD.

This has been a very tricky project due to a variety of HD formats - HDCAM, DVCPRO HD, HDV, Uncompressed, but they have all been converted to Photo JPEG for simplicity's sake. That much is simple enough. However, we have some issues exporting sequences to DVD for review. If we simply export with Compressor, it frequently fails while encoding with a QuickTime error 0, which when researched indicates a possible shortage of RAM. This is not the case, as the system is a MacPro with 2GB of FB-DIMM. Surely that is enough, and all of the memory is not even being used.

A workaround that works is to export the sequence as a Quicktime MOV first (using the project settings). However, this creates random flash frames. It's hard to describe, usually around an edit one or two frames will have a wildly varying overall luma level. These are created seemingly at random, and are not present in the timeline, and when direct MPEG-2 encoding does rarely succeed, they are not in there either.

We can convert the resulting MOVs into MPEG-2 with compressor after we export them, but of course the flash frames remain, and are simply dreadful to look at.

I've never come across this behavior before. Suggestions??

Thanks!
-Derek

David W. Jones · March 27th, 2007, 07:15 AM

Has the SD footage been up-converted to HD, and the field dominance been changed to reflect HD?

Derek Prestegard · March 27th, 2007, 03:08 PM

Well, all the material in question is progressive.

The SD material was captured as 29.97, as it is DV, but it's simple 3:2 pulldown. Removing this before dropping it into FCP shouldn't be necessary, right?

I am in process of conforming all the SD footage to 1080p 23.976fps just in case :)

-Derek

Derek Prestegard · April 3rd, 2007, 11:15 PM

Well, the 1080p24 upconversion (Adaptive pulldown removal, lanczos4 resizing, and FFT denoising and sharpening through AviSynth on Windows) looks fantastic, but we're still getting these wierd flash frames when we export from FCP.

Again, the bad frames are NOT in the sources, and they are NOT in an SD MPEG-2 downconversion (when this process succeeds).
-Derek

March 27th, 2007, 01:49 AM	#1
Derek Prestegard Regular Crew Join Date: Sep 2006 Location: Santa Cruz, California Posts: 30	Flash Frames and HD->SD problems in FCP Hey everyone, So I'm consulting for a project, and I am witnessing some very strange behavior. The basics - Final Cut Pro 5.1, source material is a mixture of HD (all in Photo JPEG, which is the project codec at 23.976), and 24p DV (simple 3:2 pulldown) which is a low resolution version of super 16 film that will later be onlined to HD. This has been a very tricky project due to a variety of HD formats - HDCAM, DVCPRO HD, HDV, Uncompressed, but they have all been converted to Photo JPEG for simplicity's sake. That much is simple enough. However, we have some issues exporting sequences to DVD for review. If we simply export with Compressor, it frequently fails while encoding with a QuickTime error 0, which when researched indicates a possible shortage of RAM. This is not the case, as the system is a MacPro with 2GB of FB-DIMM. Surely that is enough, and all of the memory is not even being used. A workaround that works is to export the sequence as a Quicktime MOV first (using the project settings). However, this creates random flash frames. It's hard to describe, usually around an edit one or two frames will have a wildly varying overall luma level. These are created seemingly at random, and are not present in the timeline, and when direct MPEG-2 encoding does rarely succeed, they are not in there either. We can convert the resulting MOVs into MPEG-2 with compressor after we export them, but of course the flash frames remain, and are simply dreadful to look at. I've never come across this behavior before. Suggestions?? Thanks! -Derek

March 27th, 2007, 07:15 AM	#2
David W. Jones Trustee Join Date: Dec 2006 Location: Little Rock Posts: 1,383	Has the SD footage been up-converted to HD, and the field dominance been changed to reflect HD?

March 27th, 2007, 03:08 PM	#3
Derek Prestegard Regular Crew Join Date: Sep 2006 Location: Santa Cruz, California Posts: 30	Well, all the material in question is progressive. The SD material was captured as 29.97, as it is DV, but it's simple 3:2 pulldown. Removing this before dropping it into FCP shouldn't be necessary, right? I am in process of conforming all the SD footage to 1080p 23.976fps just in case :) -Derek

April 3rd, 2007, 11:15 PM	#4
Derek Prestegard Regular Crew Join Date: Sep 2006 Location: Santa Cruz, California Posts: 30	Well, the 1080p24 upconversion (Adaptive pulldown removal, lanczos4 resizing, and FFT denoising and sharpening through AviSynth on Windows) looks fantastic, but we're still getting these wierd flash frames when we export from FCP. Again, the bad frames are NOT in the sources, and they are NOT in an SD MPEG-2 downconversion (when this process succeeds). -Derek