VirtualDub - help me

[Maximilian Goof]

I installed VD for the purpose to rid off of duplicate frames (mostly work with DVD PAL content). Well my first problem that is very stupid but very important is that Virtual Dub has no reaction when I try to open video file (MP4 HEVC). I open the file from the "File" option top left but the program does not respond. I red other threads about dropped/inserted/duplicated frames and from what I understood is best to remove duplicated frames when the video is interlaced scan. But what are the exact settings? I think the right settings are those:

[Attachment 84329 - Click to enlarge]
But to this point I have video material that is deinterlaced and pixel reshaped to square pixels (aka 720x576 to 768x576) with Topaz Video. It is hard and very time consuming to repeat all those steps only for removing of duplicate frames. All that is for frame interpolation. Well, when I watch movie in 50/60fps it is hard to back to 24fps.

[manono]

You'll need VDub2 to open the MP4.

For dupe frame removal you'd best use AviSynth.

[Maximilian Goof]

Thank you for the instant reply! The first program that I tried for the same is ShutterEncoder (ffmpeg GUI version). But it requires reencoding which is highly inefficient. I wonder how it is possible something so simple to be so hard to do properly

[poisondeathray]

The first program that I tried for the same is ShutterEncoder (ffmpeg GUI version). But it requires reencoding which is highly inefficient. I wonder how it is possible something so simple to be so hard to do properly

You cannot remove frames without re-encoding, unless the video used intra-frame (I frame) only encoding . The majority of consumer videos do not use intra encoding

[Maximilian Goof]

Thank you for clarifying that! Probably will stick with VD2 or GUI ffmpeg. Avisynth or non-GUI ffmpeg are too much for me. It will take a lot of time and effort to know how to use command line!

[Maximilian Goof]

But still am not shure when to remove duplicate frames. Before or after deinterlacing?

[Maximilian Goof]

Maybe deinterlacing using losless codec.

[poisondeathray]

But still am not shure when to remove duplicate frames. Before or after deinterlacing?

It depends on what you have exactly, the details, the patterns

Maybe deinterlacing using losless codec.

Maybe

But when you re-encode with a lossless codec, and you start with lossy compressed source, the filesize will increase many times

[Maximilian Goof]

Multiple times increasing filesize is my smallest problem and I know that from decent amount of time.

[jagabo]

But still am not shure when to remove duplicate frames. Before or after deinterlacing?

Before or after, or both. Depending on the problems and your intent.

[salini]

Thanks for sharing all this helpful info,
I’m also working on DVD PAL videos and want to remove duplicate frames. I’ve tried VirtualDub2, but I’m not sure. Should I handle duplicate frames before or after deinterlacing?
Also, how can I keep the quality good without making the file size too big?

Regards,
Salini.

[Maximilian Goof]

I will try first with ShutterEncoder (GUI ffmpeg) and will share my experience. I'll try later today.

[salini]

I will try first with ShutterEncoder (GUI ffmpeg) and will share my experience. I'll try later today.

Waiting for your reply

[Maximilian Goof]

I am here. Before interpolating frames first I tried to remove duplicates with Shutter Encoder. Here's the opening screen

[Attachment 84377 - Click to enlarge]
From the "Choose Function" list I select "Output Codecs", then "H.265". From the upper left part of the window I browse for the file.

[Attachment 84380 - Click to enlarge]
On the right side I click "Advanced Features" then "Remove Duplicate Frames". I tried this approach with three different versions of one source material. First with raw quality (720x576p interlaced in MPEG 2), second filtered, deinterlaced and upscaled to 720p with Topaz Video in MKV FFV1 8-bit 4:4:4, and third filtered and upscaled to 1440p in MP4 HEVC. The processing speed on the raw material was fastest (500fps approximately), on the second one slightly less (300-400fps), on the third significantly slower (120fps). On the all processed files I don't see differences. At the metadata the results are also pretty similar but something that I do not expected is that the framerate is not 24fps what I expected but varries. Here are screenshots of the Media Info analyze in the same order, exept the first one. I will explain later why I missed it.

[Attachment 84381 - Click to enlarge]

[Attachment 84382 - Click to enlarge]
From my experience is better to remove duplicates after deinterlacing because when I remove them first, the video automatically will be transcoded into progressive scan without really be progressive (fake progressive). And again I do not see any differences for supporting this process before deinterlacing. No visually, no in process speed, no in metadata. The only reason why processing is slower after deinterlacing in Topaz is the higher resolution. I do a lot of experiments with different sets of settings but have no time to do all permutations so about the rest I extrapolate.
Because the post is long and take significant amount of time I'll stop for now. Tomorrow I'll speak for the second part - interpolation.

[jagabo]

something that I do not expected is that the framerate is not 24fps what I expected but varries.

Of course. Unguided duplicate removal will remove any kind of duplicates. If there's a fade to black shot with 1 second of black frames all but one frame may be removed. Or with cartoons character movement may change at every other frame -- many frames will be discarded leaving you with 12.5 fps segments and 24 fps (panning shots) segments.

In addition to that you are working with highly compressed sources. Some frames that were originally identical (before compression) will now have slight differences. Some frames that were originally slightly different may now be nearly identical. You can manually specify a threshold value to help eliminate false positives and false negatives but you will always get some errors.

Deinterlacing will also introduce some differences and eliminate others.

This is why the answers to whether you should eliminate duplicates before or after deinterlacing were rather vague. It really depends on the source you are starting with and what your intentions are.

[Maximilian Goof]

In addition to that you are working with highly compressed sources.

I know that but this refers to the original DVD rip and the end HEVC version. For the experiment I've used also FFVI 4:4:4. But probably will pass because to this point I did not find useful results when I interpolate frames after removing duplicates, even with the losless source.

[jagabo]

In addition to that you are working with highly compressed sources.

I know that but this refers to the original DVD rip and the end HEVC version. For the experiment I've used also FFVI 4:4:4. But probably will pass because to this point I did not find useful results when I interpolate frames after removing duplicates, even with the losless source.

The DVD is highly compressed. Decompressing it, deinterlacing, upscaling, and saving with lossless compression at best preserves all the defects of the DVD, and most likely introduced more artifacts.

[lollo]

The DVD is highly compressed. Decompressing it, deinterlacing, upscaling, and saving with lossless compression at best preserves all the defects of the DVD, and most likely introduced more artifacts.

I agree, completely useless processing.