avisynth/vdub questions

[45tripp]

How much faster than vdub is avisynth?
I've rarely used filters in vdub, and not had a stopwatch close by.

How much of the speed difference comes down to possible (almost certain) colourspace conversions?
I mostly use Vdubmod. I hear some vdubs are yv12 capable. which ones?
Are there many/any yv12 vdub filters?

If you like a vdub filter and it's possible to load into avisynth with
LoadVirtualDubPlugin()
are you gaining speed by using avisynth rather than vdub?
As you have to convert to rgb and assuming you need to convert to yv12 back again is it worth using the filter or should you seek an alternative?

ty

[manono]

How much faster than vdub is avisynth?

The speed increase can be upwards of 30%, given a YV12 source (DVD).

Q1.12: What are the main advantages and processing/encoding in YV12?

A: There are two advantages:

speed increase:
It depends entirely on the external plugins whether they will have YV12 support or not. If they have then speed increases like 25-35 percent are expected. Of course there will only be a large speed increase if both your source and target are in YV12, for example in DVD to DivX / XviD conversions.
no color conversions:
The color information doesn't get interpolated (so often) and thus stays more realistic. Even if you have to do color conversions (because your are encoding with CCE SP or TMPGEnc) you have the advantage that putting off the YV12->YUY2 (or RGB24 for TMPGEnc) conversion until the end of the script allows you to first IVTC or Deinterlace to create progressive frames. But the YV12 to YUY2 conversion for progressive frames maintains more chroma detail than it does for interlaced or field based frames.

http://avisynth.org/index.php?page=Section+1%3A+About+AviSynth#q1.1

How much of the speed difference comes down to possible (almost certain) colourspace conversions?

Most of it.

I mostly use Vdubmod. I hear some vdubs are yv12 capable. which ones?

All from 1.5.4 on.

Are there many/any yv12 vdub filters?

None.

If you like a vdub filter and it's possible to load into avisynth with LoadVirtualDubPlugin() are you gaining speed by using avisynth rather than vdub?

I believe the answer is no. However, most VDub filters have an AviSynth equivalent. And if there are other AviSynth filters being used in the script, then you can gain the speed increase for them, and only slow temporarily when the VDub filter is being used in the script.

As you have to convert to rgb and assuming you need to convert to yv12 back again is it worth using the filter or should you seek an alternative?

Of course you should use the AviSynth version, if one exists. Sometimes you might not have a choice, though.

[45tripp]

Thanks

As you have to convert to rgb and assuming you need to convert to yv12 back again is it worth using the filter or should you seek an alternative?

Of course you should use the AviSynth version, if one exists. Sometimes you might not have a choice, though.

What I meant was if you have a yv12 source and target, but like a vdub filter unavailable in avisynth, do you use it because it's better than an avisynth alternative, or do you use a 'poorer' avisynth alternative because the back and forth colourspace conversions and added encoded time don't make it worth your while?

[manono]

I thought my first answer was fine. Do you have any concrete examples, or are you just speculating?

[guns1inger]

One of the few vdub filters I use in avisynth is colormill, because it is a simple way of doing colour correction interactively. It can be set up in virtualdub, saved as a preset, then cut'n'paste into a script. However it is only RGB, so the colourspace shift still has to occur, and it is incredibly slow. I am sure that some of what it does can be replicated with Tweak in avisynth, however it takes a lot long to make the adjustments.

In general though, most of what I can do in avisynth runs 2 - 3 times faster than trying to the equivalent in virtualdub. When you are doing heavy noise cleanup one a two hour VHS capture, this is significant.

[45tripp]

I thought my first answer was fine. Do you have any concrete examples, or are you just speculating?

It was

I was simply clarifying the final part of my question.

Mostly speculation.
I did like the look of MSUs smart brightness and denoiser rgb filters. I tried them frameserving with vdub and it took forever. I thought I might ask what other people do in such cases.

One of the few vdub filters I use in avisynth is colormill, because it is a simple way of doing colour correction interactively.

I had to colour correct a long time ago once. I did it in avisynth. It was pretty painless once I found out what needed to be done.
If it happens again I'll remember to try colormill.

[guns1inger]

Colormill has a wide range of functions beyond simple brightness and contrast. I like to work visually and interactively where possible. There is an avisynth tool now that allows you to set up sliders to alter settings with a live preview, but I haven't had time to look into it yet.

[45tripp]

Actually I had chroma artefacts back then.

TMPGEnc Xpress has nice interactive sliders. But encoding does take it's time.

I gave colormill a try, looks good.
Do you know the name of this avisynth tool?

[Nelson37]

Don't do much filtering with either lately, but just to confirm that Avisynth is dramatically faster. Not even close.

But, the "interface" is a lot better with Vdub.

[45tripp]

Does anyone know the name of this avisynth filter that is similar to colormill?
Where one can download it?

ty

[guns1inger]

You can call colormill from avisynth

The tool you want to look at is AvsP

[45tripp]

Ah I see.

ty
I'll give the tool a try