BUG: Deinterlacing SD to HD with FPS change / Vegas Pro 15

Dawn32 wrote on 5/19/2018, 4:30 AM

In Vegas Pro 15 build 323 Steam (and I believe in the previous build as well) there is a bug: deinterlacing the SD footage while upscaling to HD and changing the FPS causes unacceptable visual bugs in the output file. Please read the description below.

Task: to deinterlace and upscale the interlaced legacy AVI DV 50i SD footage to 1080 24p.

System: PC Win10, Intel i7, 16G Ram, Nvidia Geforce GTX 1070, UHD 4K desktop resolution.

Footage: standard SD AVI DV PAL 576 50i (i.e. 25 fps interlaced), previously captured from DV tapes with the older versions of Sony Vegas Pro.

Vegas Pro preferences: Video -> GPU acceleration of video processing = Nvidia GTX 1070.

Project properties: 1920x1080 progressive, 24.000 fps, pixel format 8 bit (or 32 bit full range - same glitch), full resolution rendering quality - Best, motion blur - Gaussian, deinterlace method - Blend Fields or Smart Adaptive (I don't use Interpolate as it makes the picture too pixelated), resample mode - any of them (Smart Resample, Force Resample or Disable Resample - tried them all, and they don't fix the bug).

The properties of the SD footage/media in Vegas Pro are standard PAL DV defaults with field order "Lower field first", "Use project resample mode", playback rate = 1.00, undersample rate = 1.0, reduce interlace flicker = On or Off (doesn't affect the bug). There are no video FX used in the media, events, tracks or project.

Then I render the footage to any 1080 24p codec/format and always get the following bug:

- with "Blend Fields" deinterlace method: every 0,5 second or so the picture switches to blurry and then back to normal, and then again and again for the whole length of the video;

- with "Smart Adaptive" deinterlace method: every 0,5 second or so the top half of the picture shifts a few pixels up and down, up and down all the time for the whole length of the video.

With both of these glitches the output file is useless.

I tried different formats/codecs with 1080 24p - Magix Prores, AVC, Intel Hevc etc. - the result was always the same with that glitch.

This glitch is also noticeable without rendering, just in the full-screen video preview of the timeline with best full settings. So I assume it has nothing to do with the codec.

This glitch is also present when using the MPEG2 SD PAL 576 50i footage for upscaling to 1080 24p the same way and the bugs on the screen are the same as with AVI DV PAL.

I used to do exactly the same upscaling of the SD DV PAL 50i footage to 1080 24p (and "Blend Fields" deinterlacing method) on the old versions of Sony Vegas Pro and it always worked fine. So this is a sort of a newly introduced glitch. As I have lot's of legacy SD DV footage which I'm still using in HD projects, that's a serious issue for me. I believe for the other Vegas users it may be important too. There always will be a need for the old archive SD interlaced footage in the HD or 4K progressive projects (for example, in the documentaries). I hope that this bug can be fixed in the next build of Vegas Pro 15 Steam. Thank you.

 

 

 

 

Comments

Musicvid wrote on 5/19/2018, 10:31 AM

Despite the fact that SD rarely needs to be upscaled for any reason (players do it better), and runs counter to any definition of "archive," you probably will not accomplish frame rate conversion, upscale, and successful deinterlace in one operation. It requires a linear, sequential workflow as nearly as I can see.

1. Deinterlace/Upscale. Set Project properties at Best, Interpolate, and render to an intermediate at 25p.

2. For 24p, you have a number of choices. You could drop frames (resample off), squeeze the events, or resample. None are perfect, and there will be a minor cadence shift once a second. But you should not see field shift as you are now. Unless you upgrade to Twixtor, that may be the best you will see.

Others may have some thoughts here or an improved process.

Dawn32 wrote on 5/19/2018, 9:49 PM

Musicvid, you probably didn't read my post well. Thank you for your comment, but it is not very relevant.

As I mentioned in my post, "There always will be a need for the old archive SD interlaced footage in the HD or 4K progressive projects (for example, in the documentaries)." I.e. the documentary or other video itself can be shot in HD or 4K, but it still requires the old SD footage to be inserted in it. Therefore, you really need this upscaling and deinterlacing to be done in NLE (Vegas Pro), not hardware, as you need to deliver the final product (which consists of mixed resolutions footage) in 1080p or 4K. I hope this is clear now.

Also, as I mentioned in my post, "I don't use Interpolate as it makes the picture too pixelated". Blend fields worked fine for that before.

And finally, as I also mentioned in my post, "I used to do exactly the same upscaling of the SD DV PAL 50i footage to 1080 24p (and "Blend Fields" deinterlacing method) on the old versions of Sony Vegas Pro and it always worked fine. So this is a sort of a newly introduced glitch". I.e. when Vegas Pro works fine as it is supposed to (like in previous versions), you CAN accomplish frame rate conversion, upscale and successful deinterlace in one operation. I've done it many times in previous versions of Vegas Pro without any problems or bugs. I hope this is clear now as well.

I'm reporting a new BUG here. This feature was working fine before. Thank you.

 

 

 

Former user wrote on 5/19/2018, 9:53 PM

One of the usual questions is, have you tried it without GPU acceleration (just as a test) and does the glitch still appear?

Dawn32 wrote on 5/19/2018, 10:19 PM

Yes, I tried it without the GPU acceleration as a test, and the glitch still appears with the "Blend fields" deinterlacing method. "Smart adaptive" deinterlacing doesn't work without GPU acceleration.

NickHope wrote on 5/20/2018, 2:46 AM

I've tested the issue with Blend Fields and confirmed it in VP14 and 15.

I've worked out that it alternately does a blend for 12 frames and then (wrongly) an interpolate for 12 frames, which means the blended sections are softer than the interpolated sections.

It happens for me whether GPU acceleration of video processing is ON or OFF.

There is a problem with both disable resample and force resample set, but it is easier to see with disable resample, since the deinterlacing ghosting is not jumbled up with the frame-rate-conversion ghosting.

There is no problem in VP10, 12 or 13.

There is no problem with an "Interpolate fields" conversion.

There is no problem if the project is set to 1080-25p.

So the problem seems to be caused by a combination of blend-fields-deinterlacing and frame-rate-conversion in VP14 and 15.

I have reported the issue, [Ticket#2018052017001067].

However the Smart Deinterlace method works beautifully for me with my AMD HD6970 GPU. I'm not seeing any vertical movement of the top half of the video. Dawn32, as there seem to be 2 separate issues here, could you please report that specific issue at https://support2.magix.com/customer/en/vegas/form , including the NVIDIA driver version you are using?

If anyone wants to test this, there is no need to render. You can see it just by playing PAL DV footage on a 1080-24.976p timeline.

Musicvid wrote on 5/20/2018, 11:19 AM

Dawn, I appreciate your clarification of your issue. It was your use of the word "archive" that threw me off track. I've now read it in proper context.

Insertion and reformatting of SD material into larger progressive displays is a subject of a lot of discussion here, and for my purposes I would prefer Lanczos to bicubic/bilinear and yadif/spline/eedi2 to blend/interpolate for this type of work, although I've never used blend, and have almost always been able to avoid asynchronous frame rates by planning.

So THANKS for identifying a proplem i had not encountered yet in 14, and am sure doesn't exist in 8.

As for using the next tier of Deinterlace and Rescaling algorithms, Nick can point you to thousands of hours of testing he and others here have done.

Generally speaking, upscaling gets done for nonsensical and gratuitous reasons. Repurposing, as you are doing, is something I am am interested in, and hope you will continue to add to my personal knowledge base as your technique refines.

 

Musicvid wrote on 5/20/2018, 11:30 AM

And Off-Topic, you can mix formats if Blu-ray is your distribution format.

fr0sty wrote on 5/20/2018, 12:16 PM

I had the exact same thing happen to me when I was trying to render some VHS tapes I'd captured. Smart De-interlace was on in that case as well. I personally do not like the idea of relying on some deinterlacer in a TV to do a good enough job, I like having that control of a quality software solution to do it for me that I know is going to consistently produce the same results each time. So anyway, rendering produced hangs or the jumbled up pixels/frames. I was finally able to get it to work by doing a CPU only render.

 

Edit: After reading Nick's post, this may not be the same issue.

Dawn32 wrote on 5/20/2018, 11:06 PM

Thank you very much, Nick! I reported the issue (including "Smart Adaptive GPU" deinterlacing bug on GeForce GTX 1070 and the driver versions) to the support [Ticket#2018052117000941]. I also tested this problem in Vegas Pro 14 build 270, and both "Blend fields" and "Smart adaptive GPU" bugs are present there as well, exactly the same way as in 15.

Dawn32 wrote on 5/20/2018, 11:08 PM

I personally do not like the idea of relying on some deinterlacer in a TV to do a good enough job, I like having that control of a quality software solution to do it for me that I know is going to consistently produce the same results each time.

 

Exactly! Good point, fr0sty.

NickHope wrote on 5/22/2018, 3:04 AM

I had a reply from Support that included this:

"Thank you for your message. We have gone ahead and created a PEF for this issue. Thank you for bringing this to our attention and we hope to have this resolved soon!"

I have previously been told that creating a "PEF" means an issue has been escalated to the development and QA team to see if it is a bug or a design choice.

Dawn32 wrote on 5/22/2018, 3:26 AM

Thank you, Nick. I had the similar reply from the Support as well. Hope they will fix the bug in the next VP 15 update (including Steam version).