video not opening in virtualdub

[shans]

I use a free onscreen recorder which saves the recorded video by default in mkv container with MPEG-4 visual video and AC3 audio formats.
I tried to open the video in VirtualDub to edit the video, but it does not show up. What plugin do I install in virtualdub? I would appreciate for any help by giving the link too.

[sum_guy]

You need the directshow plugin

http://forums.virtualdub.org/index.php?act=ST&f=7&t=15093

[shans]

You need the directshow plugin

http://forums.virtualdub.org/index.php?act=ST&f=7&t=15093

I have downloaded the directshow plugin from the above link and put it into plugins32 folder. Eventhen it does not open the video.

[jagabo]

You need an MPEG 4 Part 2 decoder like Xvid, Divx, or ffmpeg.

There may be another problem: The video is encoded with an odd frame height, 351 lines. Most decoders will not like that. Some decoders won't like the mod2 frame width either (566 columns).

[racer-x]

Delete the DirectShow plugin and put the latest ffmpeg input driver in there instead. Now drag and drop your video into Virtualdub.

http://forums.virtualdub.org/index.php?act=ST&f=7&t=20025&

[shans]

You need an MPEG 4 Part 2 decoder like Xvid, Divx, or ffmpeg.

There may be another problem: The video is encoded with an odd frame height, 351 lines. Most decoders will not like that. Some decoders won't like the mod2 frame width either (566 columns).

I have put the latest ffmpeg static plugin into plugins32 folder. However, the video didn't open. When I changed the 'Files of type" to 'FFMpeg supported files' in the files open window, it finally showed up and I could do further processing. I could even open an odd frame sized video too. Thank you.

@ racer-x - Thanks for your response too.

[jagabo]

I have put the latest ffmpeg static plugin into plugins32 folder. However, the video didn't open. When I changed the 'Files of type" to 'FFMpeg supported files' in the files open window, it finally showed up and I could do further processing.

When there are multiple plugins that can open a file type VirtualDub picks the first one it encounters. So if you didn't delete the DirectShow plugin, or if you had some other plugin that can open the container, it picked one of those instead.

[pippas]

Delete the DirectShow plugin and put the latest ffmpeg input driver in there instead. Now drag and drop your video into Virtualdub.

http://forums.virtualdub.org/index.php?act=ST&f=7&t=20025&

I too have followed that advice, and can now open my AVCHD .m2ts files in Virtualdub....So thanks for that suggestion racer-x

I'd like to convert those .m2ts files to Grass Valley HQX or Cineform directly from within Virtualdub. I have both those codecs installed, and both are visible in my Virtualdub 'Video > compression' list. But I can't convert the AVCHD to either format - I get an - 'unable to initialize video compression' error.

I can convert to Lagarith and then to Grass Valley or Cineform within Vdub, but not directly........Obviously something I've not understood here..

Is it possible to do a direct conversion, or is that function not permitted by the ffmpeg input driver?

Edit: I have managed to get the process to work by changing the color depth decompression format from 'Autoselect' to one of the other formats. Not sure which one I should be using for best results though?...... In the Virtualdub filter list, my .m2ts file color space is given as 'YUV 420'.

Unfortunately that exact description doesn't appear in any of the Vdub color depth presets. There are several almost the same.. but not 'YUV 420'.

'24bit RGB(888)' seems to work OK?.....

(my original files are 1920x1080 50i .m2ts files taken from my Panasonic SD5 camcorder)

[pippas]

Well further to my post above, I've done some experiments to try and quantify what actually happens - color display wise - when opening my .MTS files in Virtualdub, wiith the ffMpeg input driver installed.

I created a color bar video clip using the generator on my camcorder. Playing that back using WMP or MPC-HC shows the camera color bar generator has created bars with a 75% SMPTE value (RGB values of c.191)

If I open the same raw .MTS file from within Vdub, it displays the color bars with 100% values in the Vdub window.

The video clip itself reports a 'YUV 420' color space. The list of Vdub color depth decompression formats does not include that option. Using the most obvious candidate from their list -( 4:2:2 YCbCr (YUY2)) - generates an HQX or Cineform file with the same 75% values, so that would seem to be the best option.

Using their 24bit RGB (888) option generates an HQX file with 100% values -- the same as the original MTS file when displayed in the Vdub window.

Outputting my final x.264 edited files from Vdub give me the option to select either an RGB or YUV4:2:0 color space (Or indeed one of several others)

As I understand it, Virtualdub filters work within RGB color space, so it might make more sense to convert to RGB at the start and then convert back to YUV 4:2:0 only at the very end? Except it seems as if some Avisynth filters need to work in YUV color space?.....

All very confusing .... but plenty of room to experiment!

Trying to understand all these different color space options seems to be quite a challenge... There is of course plenty of information out there, but where there are so many different parameters discussed, it often difficult to make sense of it all - especially when different articles appear to offer different answers , on occasion.....

I'm wondering if some of this is 'legacy' stuff from analogue TV days?.......

[jagabo]

First try using Video -> Fast Recompress Mode. That will pass decompressed frames of the source directly to the output codec.

VirtualDub almost always displays videos with the standard rec.601 matrix. HD camcorders normally use rec.709. But DSLRs often use PC.601. Upload a short sample of your color bars video.

[pippas]

Thanks, I'll try the fast recompress mode.....(EDIT: works well!.. thanks again for the tip)
Attached is a 'raw' sample of my color bar clip. As I say, its from my Panasonic SD5, so it's interlaced - and it's PAL. (Don't think that makes any difference here though?...)

[jagabo]

The color bars use rec.709. If you use Fast Recompress mode there will be no conversion to RGB so you should get the correct colors in the output file. If the codec has some way of flagging the matrix set it to rec.709 (aka bt.709). VirtualDub may or may not display the correct colors depending on how it's set up. The RGB components should be either 192 or 0 (rounding errors when converting YUV to RGB will result in plus or minus one unit deviation) except for the white bar which should be 255. Here's what the colors should look like on the top, and the incorrect rec.601 interpretation on the bottom:




Some more info on color matrices:
https://forum.videohelp.com/threads/329866-incorrect-collor-display-in-video-playback?p...=1#post2045481
https://forum.videohelp.com/threads/329866-incorrect-collor-display-in-video-playback?p...=1#post2045830

[pippas]

Thanks for the info and the links regarding the matrices. The Grass Valley HQX codec doesn't seem to offer any choice of matrix, although their earlier HQ codec does.
I was keen to see how the conversion from AVCHD to HQX would work using Virtualdub, as an alternative to using Grass Valley's own converter utility.
Some folk have trouble using that without having Edius installed - but not everyone does?.. strange.

Using the Fast re-compress mode in Virtualdub seems to present the same color space result as their converter, so thanks again for that suggestion. My own camcorder records interlaced footage (it is quite old!) and I find the Grass Valley converter seems to give better de-interlacing results than from within Vdub, so I'll probably carry on using that myself at present.

However, with the ffMpeg input driver installed as a Vdub plugin, and the free Grass Valley HQX codec installed, it's quite useful to have a simple alternative way of converting to an intermediate format without the need to generate the much larger files that formats like Lagarith would need......

Thanks again for the info on color space matrices.....

[jagabo]

Be careful, VirtualDub does not handle the chroma channels of interlaced YV12 (YUV 4:2:0) video correctly. It will blur colors of the two fields together. This will be noticeable when colored objects move quickly.

[pippas]

So if I did want to de-interlace within Vdub, I would be better to convert to RGB and de-interlace in that color space, and then convert back to YUV 4:2:0 in my final x.264 output conversion?.....

[jagabo]

Yes, or YUY2. But the best deinterlacer by far is QTGMC() in AviSynth.