Questions on basics of Avisynth

[Roman Helmet]

Hi all you l33t avisynth users out there. I am a severe n00b at avisynth and have some questions. I hope somebody can answer them for me. Okay, here we go.

1)Why should I use avisynth in the first place? What advantages does it have?

2)What are these color things such as YUV and RGB? How do I know when I need to change between them, and what exactly are they?

3)What is the advantage of using avisynth over using just virtualdub filters and such? My main use for avisynth is going to be applying various filters.

4)Is there any kind of advantage to loading and using the virtualdub filters you are going to use into avisynth instead of just using them through virtualdub?

5)Is encoding time faster overall using avisynth than virtualdub for filters?

6)And finally, how in the heck did you guys learn so much about using avisynth? It is so overwhelming to learn.

[Tuning]

Hello Roman Helmet,Welcome to Doom9 forums,

All of your questions would have got answers by simple search.
And Searching is the no#1 forum rule.Look here for rest 15 forum rules here (http://forum.doom9.org/forum-rules.htm).

Your questions from 1-5 have answers in

Avisynth FAQ (http://forum.doom9.org/showthread.php?s=&threadid=25002) and YV12 FAQ (http://forum.doom9.org/showthread.php?s=&threadid=37276).

And finally for learning visit www.avisynth.org (http://www.avisynth.org/)

[stickboy]

Originally posted by Roman Helmet
1)Why should I use avisynth in the first place? What advantages does it have?Among other things:
AviSynth supports non-linear editing, supports different color-spaces, and easily allows you to create and share re-usable functions and scripts.

See the mirror of Ben Rudiak-Gould's original AviSynth site (http://www.neuron2.net/www.math.berkeley.edu/benrg/avisynth.html) that lists various advantages and disadvantages of AviSynth vs. VirtualDub.
2)What are these color things such as YUV and RGB? How do I know when I need to change between them, and what exactly are they?They're different ways of representing colors. RGB represents each pixel in terms of shades of red, green, and blue. YUV instead represents pixels in terms of luminance (lightness/darkness) and chroma (color information).

It's to my understanding that YUY2 and YV12 are particular formats that use the YUV colorspace. YUY2 and YV12 have different sampling systems; they take advantage of human perception and store the color information at lower-resolutions than the luminance information. YUY2 stores an average of 16 bits of data per pixel; YV12 stores an average of 12 bits of data per pixel.
3)What is the advantage of using avisynth over using just virtualdub filters and such? My main use for avisynth is going to be applying various filters.Filtering in AviSynth can be faster (more on that later). More importantly to me, AviSynth allows you to apply different combinations of filters or different segments of video easily. Want to filter one scene more aggressively than another? No problem.

Filter settings you use in AviSynth are also self-documenting and self-archiving. It's easy in VirtualDub to fiddle around with some filter setting, use it once, and forget about it, never having saved nor written down what settings you used.

AviSynth can use any VirtualDub filter (except for the internal VirtualDub ones), but VirtualDub cannot use AviSynth ones directly. Therefore, using AviSynth also gives you more choices.
4)Is there any kind of advantage to loading and using the virtualdub filters you are going to use into avisynth instead of just using them through virtualdub?There's no immediate advantage, aside from what I said before about AviSynth scripts being self-documenting and self-archiving.
5)Is encoding time faster overall using avisynth than virtualdub for filters?If you use RGB, no. On the other hand, if you use YUY2 or YV12, there is less data to process, so by that virtue alone you can get improved performance.
6)And finally, how in the heck did you guys learn so much about using avisynth? It is so overwhelming to learn.I personally like Ben Rudiak-Gould's tutorial (http://www.neuron2.net/www.math.berkeley.edu/benrg/avisynth-tutorial.html).

You can a learn a lot by reading through the material at avisynth.org (although it could be much improved) and by lurking this forum.

[Roman Helmet]

Thanks for your help, I really appriciate it.