VirtualDub 2 vs original VirtualDub frame rate conversion

[spapakons]

Hello!
I am using the original VirtualDub since the '90s for video editing. I like the huge video filter collection and the ease of use. I have even installed whatever plugin is available in order to open as many as possible video formats. When I learned there is a more modern version VirtualDub2 where all the old filters and plugins work and even has a 64-bit version (much better than the very limited original VirtualDub 64-bit version), I downloaded it and I was about to forget the original VirtualDub and fully adopt the new version, until I tried to convert an NTSC 23.976fps video to 25fps. The picture was going a little fast then almost freeze, then going fast again. Not even close to the perfect and smooth conversion the original VirtualDub does. I read somewhere that they changed the way the frame rate conversion is done. Why? What they changed? Is there any way to switch the good old method of the original VirtualDub?

Thank you in advance.

[davexnet]

Provide a sample of your source and/or a link to the article your referring to.

[spapakons]

I cannot find it, I read it many months ago. If you have both the original VirtualDub and VirtualDub 2 convert a small video from one frame rate to another and see the difference. The output of the original is flawless while the output of the new version is stuttering, not smooth. Why is that? Is there any way to make the new version convert frame rate as good as the original?

[davexnet]

What else did you set? Did you leave it in video/full processing mode?
If so, what did you set in video/compression?

Audio? none? Full processing (which compression?) or direct stream copy?

If audio is included how did you speed up/slow down the sound to match the video?

Provide a mediainfo report (text view) of your source

[spapakons]

In both programs I simply selected to convert the fps to 25.0000 then I chose the x264vfw codec for the video. The audio is set to full mode and AC3 ACM compression. The audio sync in both outputs is perfect. It is the video of VirtualDub 2 that is far from smooth. The video of the original VirtualDub is indistinguishable from the original frame rate, exactly the desired result.

[davexnet]

Try vdub2, but do not use x264vfw, set video/compression to x264 8-bit
Open up the configure screen and select "load defaults" (lower left)

Here's a music video clip, 25>23.976 conversion in vdub2, using video compression / x264 8bit and
Audio/use advanced filtering/filters/Time stretch

[Alwyn]

Here's a music video clip, 25>23.976 conversion in vdub2

Dave, I don't know whether it makes a difference but spapakons is going the other way.

[davexnet]

Here's a music video clip, 25>23.976 conversion in vdub2

Dave, I don't know whether it makes a difference but spapakons is going the other way.

Good point - but it doesn't make a difference except for the time stretch "factor",
23.976/25 = 0.959

[spapakons]

Whoa! Compression codec is irrelevant to frame rate conversion. Even if I saved the video in a huge RGB or YUV uncompressed file, the conversion in VirtualDub 2 is not smooth and perfect (aka seamless) as is with the original VirtualDub. In 2 they changed the conversion method (probably just adding/dropping frames) and the result is stutter. The original VirtualDub didn't just add or drop frames, it actually converted to the target fps and this explains why it is perfect. Also assuming the conversion is done properly (not just add/remove frames), there should not be difference in the video duration. This means I can convert from 23.976fps to 25fps, normalize the audio independently in Adobe Audition and still remain in sync when I remux it back. I have done it many times.

Until I can find a workaround, I use VirtualDub 2 for everything else except frame rate conversion. If I have to convert (for example from 60fps of my HDMI capture card to 25fps), I always use the original VirtualDub. The result is always perfect and always in sync with the audio.

[davexnet]

If you're talling about this, it neither interpolates nor decimates to get the new frame rate,
it just retimes the existing frames, causing the new video to run fast or slower -
this is why I talked about having to stretch the audio to sync properly. (Similar to Assumefps(xx) in Avisynth )

It's always done this, both vdub2 and the original virtualdub

[spapakons]

Who said anything about "change frame rate"? This is only when you want to slow down or speedup a video, or when the frame rate taken from the video file is not the actual frame rate. In all my posts I clearly used the word "convert". I want to convert the video frame rate from 60fps or 23.976fps or whatever that is to 25fps. This is the last option in the photo, look carefully. Just leave Source rate adjustment to "no change" and at Frame rate conversion select Convert to and type the target frame rate. My complain is the that VirtualDub 2 does a lousy job while the original VirtualDub does a perfect flawless seamless conversion. Why did they change the fps conversion method? Is there any setting or Registry hack or patch or filter or whatever else to get back the good old method of the original VirtualDub? I am afraid not, but hope dies last as they say.

[jagabo]

It has always been the case that VirtualDub(2)'s "Frame Rate Conversion" simply duplicates or decimates frames to achieve the new frame rate. That does not change the runtime of the video so there's no need to adjust the length of the audio. And the duplication or decimation creates little jerks in the video. "Source Rate Adjustment" just changes the timing of the existing frames, changing the runtime of the video, introducing no jerks, but requiring adjustment of the audio.

If you're finding something different it's probably caused by the source filter -- some source filters have problems with some sources. Make sure you're using the same source filter.

[davexnet]

OK. I tried the "convert" on a short clip and it looks ok to me in Vdub2.
Couldn't produce your problem. See these samples.

[spapakons]

Convert a short clip in the original VirtualDub and then convert the same clip in VirtualDub 2. Maybe it is not that obvious from 23.976fps to 25fps, but in case of 60fps to 25fps is much more pronounced. That was what I first did, a 60fps capture from my HDMI card to 25fps and was deeply disappointed because the original VirtualDub does it smoothly, like if the original video was 25fps.

[rgr]

Convert a short clip in the original VirtualDub and then convert the same clip in VirtualDub 2. Maybe it is not that obvious from 23.976fps to 25fps, but in case of 60fps to 25fps is much more pronounced. That was what I first did, a 60fps capture from my HDMI card to 25fps and was deeply disappointed because the original VirtualDub does it smoothly, like if the original video was 25fps.

Can you post these two examples?

[davexnet]

Yes a look at the source would clear this up. I asked for this in post #2

[jagabo]

A 60p source with panning vertical lines and frame numbers. Vdub1 conversion to 25p, v2ub2 conversion to 25p. The results are identical. Simple decimation.

Though the version of vdub2 I'm using is 4 years old.

[spapakons]

If you so insist, here is a small 30sec sample. The 60fps version, the 25fps from VirtualDub 1.10.4 and the 25fps from VirtualDub2.

60fps captured from HDMI card.avi
60fps to 25fps VirtualDub 1.10.4.avi
60fps to 25fps VirtualDub2.avi

[rgr]

If you so insist, here is a small 30sec sample. The 60fps version, the 25fps from VirtualDub 1.10.4 and the 25fps from VirtualDub2.


[Attachment 81681 - Click to enlarge]

[Attachment 81682 - Click to enlarge]

[Attachment 81683 - Click to enlarge]

The source file has a lot of duplicate frames (even triplicates). VirtualDub won't do any good with this - you'll need to use AviSynth and TDecimate to remove these frames or something similar. Someone will probably advise more specifically soon.

[Alwyn]

...

[spapakons]

If you so insist, here is a small 30sec sample. The 60fps version, the 25fps from VirtualDub 1.10.4 and the 25fps from VirtualDub2.


[Attachment 81681 - Click to enlarge]

[Attachment 81682 - Click to enlarge]

[Attachment 81683 - Click to enlarge]

The source file has a lot of duplicate frames (even triplicates). VirtualDub won't do any good with this - you'll need to use AviSynth and TDecimate to remove these frames or something similar. Someone will probably advise more specifically soon.

I don't want to just remove frames, this will make the motion jerky. I want to convert from 60fps to 25fps and produce a smooth motion indistinguishable from the original 60fps version. I know other programs such as Fastflix and Handbrake can do that, but their AVC encoders are not very accurate. I calculate the bitrate with AVCHD Calculator and input to x264vfw. Then I import the resulting AVI file in MultiAVCHD to create an AVCHD folder without recompression. x264vfw gives me an appropriate master AVI file so the AVCHD folder is as close as possible to the target 4480MB and fits perfectly in a blank DVD-R disc without compromising image quality. If I use the NVEnc hardware encoder in Avidemux/Fastflix/Handbrake the resulting MKV file is rarely of the appropriate size. Importing this in MultiAVCHD will either produce a smaller AVCHD folder (for example 4300MB) which is unacceptable, or a larger than 4480MB which won't fit an a blank disc. So I cannot benefit from their perfect frame conversion and much faster video encoding. If I want to be close to 4480MB my only choice is VirtualDub 1.10.4 (if frame rate is involved) or VirtualDub2. Unless I find something else that respects my bitrate setting and produces accurate file sizes.

PS: Yes, I have tried x264 codec, it is barely faster than using VirtualDub with x264vfw and not very accurate. Other suggestions? Cuda Coder also is very fast but sadly not accurate (it doesn't always respects my set bitrate).

[jagabo]

If you so insist, here is a small 30sec sample. The 60fps version, the 25fps from VirtualDub 1.10.4 and the 25fps from VirtualDub2.

The two VirtualDub videos are identical, aside from compression artifacts. They are exceedingly jerky -- much more than one would expect from simple decimation of that source video. I think you have having problems with the source filter. For what it's worth, I've attached 25 fps versions using a proper simple decimation (what VirtualDub should have delivered), and another using smart decimation (which preferentially removes duplicate frames) in AviSynth.

I don't want to just remove frames, this will make the motion jerky. I want to convert from 60fps to 25fps and produce a smooth motion indistinguishable from the original 60fps version. I know other programs such as Fastflix and Handbrake can do that

I've never used fastfix, but Handbrake uses simple decimation to reduce the frame rate, the same as VirtualDub.

But, as was pointed out by rgr, your source video has tons of duplicate frames, with an irregular cadence, making it jerky to start with. You need to fix your capture process. To get a smoother result from that 60p file you will first have to remove all the duplicate frames, then use a motion compensated frame rate converter. And 25 fps will never give as smooth motion as 60 fps, even with a perfect conversion.

For what it's worth, here's a version using a proper simple decimation, and another using smart decimation (which preferentially removes duplicate frames) in AviSynth. It's better than the dumb decimation from VirtualDub.