Why people are disapproving opening video files with VirtualDub?

[tip]

Hi to all,

I'm pretty much a newbie when it comes to video encoding... I've read a lot about it in the past few weeks and I think I understood how things work in general :).

I've got two questions:

1) People often disapprove opening video files in virtualdub(MOD) and then encode it. They say it is better to use avisynth.

Can anybody explain me the reason of it?

They say that it is because Virtualdub is still using vfw which is outdated etc. but I still don't understand why it hurts the quality of the encoding.

2) Is it better to use meGUI(or basically avs + xvid encraw) compared to creating an avisynth script then opening it with virtualdub and encode it using xvid? (with same encoding options and using same xvidcore.dll ofcourse :D) If so, can you explain why?
I've encoded some videos for test this one but I couldn't find a difference worth mentioning. I think colors are a bit different in some scenes but...


Thanks everybody in advance.

Regards
Tip

[stax76]

I guess you mean VFW (Video For Windows), AviSynth is based on that too, it has some mostly codec related limitations. The reason why AviSynth is so popular is it's very powerful, there might not be a big difference using MeGUI with encraw or VirtualDub(Mod), different GUI but the results will be mostly the same, MeGUI is probably easier to use.

[tip]

Thanks for clearing this up for me.

I have one last question:

Is there better way to encode in xvid then? I mean if avisynth and virtualdub both uses vfw (which is referred to be a bad thing. I don't know why) then is it better to use a linux machine?

Regards
Tip

[stax76]

It has some limitations but it's not bad because of that, on linux they use applications like mencoder and ffmpeg, that tools work on Windows just as good.

[tip]

Thanks again. You've been most helpful.

Regards
Tip

[mariush]

There's nothing wrong with Virtualdub, just encoding to H264 with it is wrong. Virtualdub only supports Video For Windows for encoding and the h264 codec (x264 vfw) is not able to use all the features the regular command line encoder can use because the Video For Windows standard is very old.

Avisynth does use Video For Windows but can also use DirectShow to open video files and serve video and audio frames to applications but then what applications do with them it doesn't care.

VirtualdubMOD is very old and if I remember correctly it has some very old libraries and code regarding MKV so it's not able to open properly some newer MKV files and could even output MKV files that are not properly supported by some players.
Otherwise... same thing that applies to Virtualdub applies to Virtualdubmod too.

[manono]

1) People often disapprove opening video files in virtualdub(MOD) and then encode it. They say it is better to use avisynth.

Can anybody explain me the reason of it?
Using AviSynth scripts allows you to use Fast Recompress while filtering an AVI directly in VDub(Mod) means you use Full Compression with the resulting colorspace changes into and back out of RGB. The resulting quality frameserving via an AviSynth script is slightly better (truer colors, less blurring). Also, by keeping it in YV12 all the way (assuming that's what it is originally), the encoding goes about 30% faster.

Read the top two questions:

http://avisynth.org/mediawiki/YV12#What_will_be_the_main_advantages_of_processing_in_YV12.3F

[GodofaGap]

Using AviSynth scripts allows you to use Fast Recompress while filtering an AVI directly in VDub(Mod) means you use Full Compression with the resulting colorspace changes into and back out of RGB. The resulting quality frameserving via an AviSynth script is slightly better (truer colors, less blurring). Also, by keeping it in YV12 all the way (assuming that's what it is originally), the encoding goes about 30% faster.
VirtualDub doesn't do that for a long time anymore, and most of the internal filters support YV12/YUY2 now.

[Hagbard23]

Is it better to use meGUI(or basically avs + xvid encraw)

Some people say, that EncRaw is buggy - i cannot confirm that, but XviD was originally programmed for VfW - later on the commandline-version followed, so i just stay at the VfW thing, because it worked good all the time. I can see nothing "bad" with VfW.

Also: i cannot confirm, that <most> of the VD-Filters support YV12. A significant number of filters (including some -fine- MSU Filters) do NOT support YV12. That is why most people, that do reencoding from DVD's or BD's do not use Virtual Dub's Filter Section.

But: There are many people who are reencoding from DV or Homemade Stuff, or old 8mm video and so on. For that purpose it might be better to use only a small AviSynth Script and do the rest of the filtering via Virtual Dub - but that depends.

For me Virtual Dub is still the first choice for fast recompression and VfW is just the easiest way for me to interface XviD. So for me it is not the question "VD or AvS" but "VD AND AvS".

[manono]

VirtualDub doesn't do that for a long time anymore, and most of the internal filters support YV12/YUY2 now.
Really? Are you sure about that? If so, then I stand corrected, although tip (the OP) specifically asked about VDubMod (I think), which I still use myself when I need to use a VDub of some sort.

Edit: After doing some checking around I see you're right - that by changing the Color Depth it's possible to keep a YUV colorspace (YV12 in this case, I suppose) and still use Full Processing. Thanks for the correction.