What is acceptable for quality of source footage?

Torchlight · Post by **Torchlight** » Thu Apr 01, 2004 4:35 pm

Hey y'all:

I've been working again recently on some Trigun footage using the Region 1 Trigun boxed set. Using AVIsynth, my plan was to, of course, IVTC and have nice progressive 24 fps footage for Premiere.

However, I have run into problem after problem as it seems that this footage does not IVTC nicely (anyone worked with Trigun DVDs before? any comments?) Using the Decomb filter in my AVIsynth script with default options, I still get combing artifacts all over the place like this:

Obviously not acceptable, so I spent some hours tweaking with Decombs options (which I am glad to have had the opportunity to do because now I'm much more familiar with Decomb's capabilities!). Now, I'm at a point where I'm pretty much rid of noticeable combing artifacts, but there is an undesireable side effect.

Let me illustrate with two screenshots of the exact same frame.... the first frame is how it should look - I got this frame by loading the d2v without running any IVTC. The second frame is with Decomb active...

Now, to me, the difference is quite noticeable, but maybe that's just because I've been working with this footage so much lately. In the second shot, you can really notice the problem around Vash's mouth and eyes, the lines on his upper cheek, and the edges of his coat. What were nice, bold, solid lines before are now soft, loose, and "chunky." With the footage that has been IVTC'd, this is very common in almost all frames.

Now, at first glance, it doesn't seem so bad, but please keep in mind that this is just a still shot. With this happening in every frame, once the footage is played, the footage looks poor when compared to what it should look like. Because of the soft lines, the footage looks "washed out" and takes on a sort of "VHS Capture" quality.

Of course, if anyone has any technical suggestions or ideas for me, I'd love to hear them. But, the reason I posted this here instead of in Software Help is because I'm starting to consider the possibility that there may not be a way for me to get the kind of IVTC I want from these DVDs.

I've got some cool stuff planned for this vid and its not going to be a 4-hour project, by any means - I'd really like to sink my teeth into this one. Because of this, though, I'd hate to put in a ton of work into a project that even with great editing, ideas, and execution, won't look that great or be considered a "good vid" because the source looks crappy.

I think of a video like "Euphoria" - not only is it an amazing edit, but the footage is clean and beautiful. Would it have been as well recieved if the footage wasn't the greatest?

I guess I'm just looking for some thoughts, opinions, discussion - what are the standards for source quality these days? Is my footage as bad as I think it looks after IVTC? (Maybe I'm just overanalyzing) If I was somehow able to produce a great edit, would my vid still be bumped down a notch by having the lesser footage quality as explained above.

Kind of a ramble, now that I read it over, but I would love to hear anyone's thoughts or opinions - thanks in advance!

-T

AbsoluteDestiny · Post by **AbsoluteDestiny** » Thu Apr 01, 2004 5:05 pm

Your IVTC errors are due to post-processing and bad field matching. You'd need to mess with the settings to avoid these.

Torchlight · Post by **Torchlight** » Thu Apr 01, 2004 5:23 pm

k - i'll go back and try a few more settings with Decomb.

*heads back into the fray with hope on his mind*

AbsoluteDestiny · Post by **AbsoluteDestiny** » Thu Apr 01, 2004 5:26 pm

With IVTC it's a case of give an take. If good matches can't be found you can often have "bad" ones put in that make the motion smoother. Look at the documentation and it explains it in more detail.

Trigun is a really troublesome source, though - old school telecine and encoding. Not very pleasent.

Torchlight · Post by **Torchlight** » Thu Apr 01, 2004 6:02 pm

AD - thanks again sooo much for your advice and the way you gave it. I took another read through Decomb's documentation, played around a little bit more and then realized that I had vthresh set way too low. I still get some slight combing during pans, but I am confident that I can tweak those out as well or that I will most likely not be using panning footage in my project.

Thanks for helping me help myself and giving me advice that helped me not only to fix my problem, but also figure it out for myself. I will be better off in the future because I understand the theory behind what was going wrong.

Thanks! WOOOHOOO! 8)