VirtualDubMod mpeg2 framerate

[jagabo]

i've got a question for jagabo:
I was taught mpeg color system is YV12 (right?)

YV12 is used on DVD but MPEG2 does have the ability to encode with YUY2 internally. TMPGEnc Plus has support for YUY2.

So if i've got a source which is coded in yuv2 system i should preferably pick yuv2 to decode it an then pick 4.2.0 planar (yv12) to output it (because i will encode in mpeg via the frameserver)

Genrerally the MPEG encoder will take what you feed it and convert to YV12. Though some encoders may only accept certain colorspaces. Or they may work better and/or faster with certain colorspaces. CCE likes YUY2 input best.

So far i used vdubmod and used the 24bits c.depth and i hadn't lots of problems with the quality.. but i'm tryin to step up my game

For the most part, VirtualDub's RGB filtering isn't so bad. It's just a little slow compared to AVISynth. If your source is YUV with areas below IRE 0 (luma below 16) or above IRE 100 (luma above 235) AVISynth may be able to bring out details in those areas. VirtualDub won't.

[45tripp]

In short, all programs open the CCE encoded MPV file and decode to RGB giving colors similar to the original uncomrpess RGB AVI. Only VirtualDubMod gives different colors, colors that correspond to using AVISynth's ConvertToRGB(matrix="rec709").

It seems vdubmod uses the rec709 matrix coefficients to convert to rgb,
whereas vdubmpeg2 uses 601.
One should say vdubmod defaults to 709, as it's capable of using 601 if the mpeg header so dictates, and vdubmpeg2 can only use 601.
TMPG writes a colour matrix flag in the header, cce doesn't. If opened in gspot one can see if the info is in the header or not. That would be why tmpg output in vdubmod is the same as in vdubmpeg2 (fcc flag). If you use a tool to strip the stream of the info you'll get the same effect with tmpg output as you get with cce in vdubmod.

[_migz_]

guys, i have one last question.. somethings buggin be bout DGIndex.. In DGIndex, in the "Video" drop down menu, there's YUV->RGB right? when you save the project and load that in an AVISynth Script, does it mean that it converts the colorspace of a source like a DVD to RGB??... isn't that bad??

[jagabo]

In DGIndex, in the "Video" drop down menu, there's YUV->RGB right?

I believe that only effects the display window in DGIndex.

[_migz_]

ohhh! ok thanks jagabo.

[wiseant]

Hi All, Just finished registering . . . just wanted to say thanks for all this great information

By the way, I did some colour tests using QuEnc, HC_021, CCE, and MainConcept as well as using Avisynth, VirtualDub and VirtualDubMPEG2 - I'll try to find this info if anyone is interested

And once again: this forum at videohelp.com is excellent

[manono]

In DGIndex, in the "Video" drop down menu, there's YUV->RGB right?

I believe that only effects the display window in DGIndex.

And if you're using the obsolete VFAPI method of frameserving.

[jagabo]

I did some colour tests using QuEnc, HC_021, CCE, and MainConcept as well as using Avisynth, VirtualDub and VirtualDubMPEG2 - I'll try to find this info if anyone is interested

I'd like to hear about them!

[wiseant]

Hi jagabo
They've temporarily gone missing - i.e. they are on a DVD backup somewhere - but as soon as I find them I will post this info.

[themaster1]

Considering vdub mpeg2 works in yv12 only in "fast recompress mode" from what i understand (no filtering possible) i'll stick with vdubmod.Plus like i said i had very good result(see this thread)

Actually i don't know what could be the interest to use this soft except that it support pulldown

[jagabo]

Considering vdub mpeg2 works in yv12 only in "fast recompress mode"

All the VirtualDub variants are the same in that respect. Actually that isn't quite accurate. In fast recompress mode all VirtualDub variants pass the digitial video through to the compression codec in whatever form it arrives from the source. If they receive YV12 they ouput YV12. If they recieve YUY2 they output YUY2. If they recieve RGB they output RGB.

[manono]

Never mind.

[wiseant]

Hi jagabo
Sorry for the delay - I checked my DVD backup re my colour tests and found that most of the data was corrupted - don't know why - so until I repeat my tests I don't have any info to share . . .

[jagabo]

Too bad. Thanks anyway.

[45tripp]

YV12 is used on DVD but MPEG2 does have the ability to encode with YUY2 internally. TMPGEnc Plus has support for YUY2.

Could you explain what you mean?

All info I've seen is pretty conclusive, TMPG accepts RGB input only.

[jagabo]

YV12 is used on DVD but MPEG2 does have the ability to encode with YUY2 internally. TMPGEnc Plus has support for YUY2.

Could you explain what you mean?

All info I've seen is pretty conclusive, TMPG accepts RGB input only.

I wasn't refering to the input to TMPGEnc but the 4:2:2 chroma subsampling that can be used internally in the MPEG stream (rather than the usual 4:2:0).

[Cornucopia]

I've used Canopus (reference, type 1) DV-AVI files as input to TMPGEnc Plus for 4-5 years now, no problem, so I know it'll accept other than RGB (as DV is YV12). I think it depends upon which codec you're using (and which ones it'll accept). May be adjustable with that "DLL Priority" settings table.

Scott

[jagabo]

Yes, TMPGEnc Plus accepts YUY2 and YV12 sources. I believe it converts frames to RGB before doing anything with them though.