Issue with video file

Toshi.des · Post by **Toshi.des** » Fri Apr 18, 2008 10:55 am

I have a .mkv file that's properties say it's 720x480 and is 29.97 fps, but it actually plays at 850x480 and is more like 24 fps when using media player classic. When playing at 850x480 though everything is in proportion and the audio syncs with the video like it should.

It's when I use virtual dub and use "directshowsource" that issues start to arise. When saved as an .avi from VDMod it comes out as the original properties of 720 by 480 at 29.97 fps.

At that resolution things are distorted, I can stretch them out to 850 width but from my memory using premiere to do that would makes your video loose some detail. But the other issue that I really want to fix is that the speed of the video is a lot faster. Looks like the video has been speed up, while it's very smooth it just doesn't look normal. Also I was planning on using some of the audio from the original footage yet now the audio wont match since it's moving faster than the audio.

Any ideas how to fix this? or change this?

Bauzi · Post by **Bauzi** » Fri Apr 18, 2008 11:18 am

You can set some options in some containers like .mp4 or .mkv how the files should be displayed. So in your case they encoded it in 720x480 and told the container to display at another ressolution.
My thought is that it´s natural that VDM "converts" it to the original 720x480. What can you do against it? Well add a simpel resize option at the end of your script, like LanczosResize() . I think it should help.

I really don´t know about why your framerate error occurs, maybe it´s the same like with the ressolution, but I really doubt it.
A sollution would be to add at the end of your script:
AssumeFPS(29.97)

Your vid should be in 29.97 now.

I didn´t tested this method so I might be wrong.

Toshi.des · Post by **Toshi.des** » Fri Apr 18, 2008 11:34 am

I've been trying to use BicubicResize(850,480) but keep getting this error:
YUY images for output must have a width divisible by 4 (use crop)!

Same thing happens when I try to use LanczosResize.

would AssumeFPS work to slow down the fps? the issue is that it seem to be running to fast at 29.97 fps so I think it's most likely 24 that it actually should be running at.

Bauzi · Post by **Bauzi** » Fri Apr 18, 2008 11:43 am

Ok I can´t help you with your resize problem.

Yeah you could stick on 720x480 for your project and use a different aspect ratio for playback like 4:3 or 16:9. It´s really easy if you make a proper mp4 with zarxGUI:
http://www.animemusicvideos.org/guides/ ... 64gui.html
(stands under Sample Aspect Ratio)

24 that it actually should be running at.

Well than try it! Or use 23.978.

In the end you can still take control over the speed of your scenes in your editing software.

LivingFlame · Post by **LivingFlame** » Fri Apr 18, 2008 12:12 pm

Toshi.des wrote:I've been trying to use BicubicResize(850,480) but keep getting this error:
YUY images for output must have a width divisible by 4 (use crop)!

It means that if you actually do the math of the video dimensions (i.e. 850x480, in your case) the product has to be divisible by 4. And it just so happens 850x480 is 408,000, which is not divisible by 4.

Use 848x480.

(848x480=407,040. That is divisible by 4. (Divided, it comes out to 101,760.))