1.5 hour video (HD convert to DVD in Compressor) bad only in spots

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1.5 hour video (HD convert to DVD in Compressor) bad only in spots

As the subject heading says, I am taking HD video exported as self-contained from FCP 7 and converting to SD (DVD) in Compressor 3.5.3.

I know there will be quality loss, that's not the issue. The problem is that no matter how many time I re-export, re-burn, the final video on DVD gets really bad in the same two spots (and last for a couple minutes). By "bad" I mean very pixelated and jumpy (sorry, "jumpy" is the best work I can think of to describe the flickering occuring).

I'm at a loss, and really confused as to why it would keep occuring at the same two spots (and yes, the original export is crystal clear the whole way through, even in those two spots). Both times this occurs it is towards the end of the video. First at around 1 hour 10 minutes, then at about 1 hour 25 minutes through the end of the video.

I hesitate to say this because I'm not 100% certain, but it almost seems like the quality gets worse as the video goes on, but it might just be me.

Help or advice would be greatly appreciated.

Thank you,

Eric

MacPro / PowerBook G4, Mac OS X (10.6.6), FCP 7.0.3

Posted on Dec 1, 2012 6:06 AM

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Answer 1

Best reply

Russ H

Level 7

22,432 points

Dec 1, 2012 6:22 AM in response to Eric Pensenstadler

Eric Pensenstadler wrote:

As the subject heading says, I am taking HD video exported as self-contained from FCP 7 and converting to SD (DVD) in Compressor 3.5.3.

What kind of HD video (codec, frame size, frame rate)?

Try testing only the problematic sections by marking in and out points in the Preview window - say two separate 2 minute files. If the artifacts are still present in these test files, try inserting compression markers at the point where the problems first appear. If they the problems don't appear on the test segments, turn on frame controls and set Resize Filter to Best and re-encode. (Sorry…this will take a while.)

Russ

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Answer 2

Dec 2, 2012 8:48 AM in response to Russ H

Russ,

Thank you for your quick reply yesterday. After your post the day was spent experimenting based on your advice - unfortunately to no avail!

Here is what I found for those following this thread:

>>Try testing only the problematic sections by marking in and out points in the Preview window - say two separate 2 minute files. If the artifacts are still present in these test files, try inserting compression markers at the point where the problems first appear.

RESULT: The artifacting is still there, although it seemed to start a little later (in other words, not in exactly the same spot). So, I set compression markers at the points in the video and re-exported as QuickTime Movie from FCP 7. Upon burn of DVD, not only was the artifacting and jitters still there in the same spots, but Compressor did not create chapters on the DVD despite the Inspector showing them in the little menu preview window and Markers being checked.

>>If the problems don't appear on the test segments, turn on frame controls and set Resize Filter to Best and re-encode.

RESULT: Maybe I just don't know Compressor well enough, but I couldn't make this work. When I open Compressor to burn a DVD (or a BluRay) I simply choose the DVD option from the drop down box that automattically appears, and then make the wanted tweaks in the Inspector (chapters, adding background, etc). In order to turn on Frame Controls, I had to use one of the Settings in the Settings window - this would have been fine, but as soon as I hit Submit the Inspector window diverted back to the windows/options just noted above, and I got the exact same result as the first time - that being a DVD with no chapters and still the artifacting.

As I said, I may not be doing something right, but I tried for a long time.

>>(Sorry…this will take a while.)

It didn't seem to take any longer than normal, which was about 6 hours for a 1.5 hour video.

I'd still welcome any more feedback. But for now I'm making the discs and sending them out and if anybody complains then I'll just tell them that the drawback of converting HD to DVD. They should get the bluray!

Thank you,

Eric

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Answer 3

Russ H

Level 7

22,432 points

Dec 2, 2012 9:46 AM in response to Eric Pensenstadler

H

Eric Pensenstadler wrote:

I'd still welcome any more feedback. But for now I'm making the discs and sending them out and if anybody complains then I'll just tell them that the drawback of converting HD to DVD. They should get the bluray!

Thank you,

Eric

Hey Eric,

That's a great attitude!

If you're interested in exploring this further, here are some screen shots to illustrate some adjustments that might help.

First, starting with the standard preset.

With the job selected, in Exttras, I've set the output device to HD (so I can make multiple copies and tests).

In the Inspector>Encoder, I can adjust the bit rate to make sure the content will fit on a single layer DVD, On this case, I have chosen CBR @ 4.5 Mbps; If it were a sort movie, I might go as high as 7.5 Mbps.

In the Inspector>Frame Controls, I've turned on Frame Controls and set the Resize Filter to Best (Statistical Prediction). It's going to be re-sized from 1080 to 480 so it needs all the help I can give it.

Looking at the Summary pane, I can confirm the changes that were made to the settings will be applied.

I can save this as a custom setting if I want.

You're right that going from HD to SD MPEG2 can be problematic. So much is content dependent, that it's hard to give a one-size-fits-all formula for success. Generally, I've had extremely favorable results and I'd much rather start out with a large amount of pixels than not.

It's possible the length of the video is a factor in generating the artifacts you see or a combination of that and the content at those points in the movie. Try some of the adjustments available through the Inspector to see whether you can come up with the correct recipe.

Good luck.

Russ

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