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vcmohan
24th September 2005, 03:43
I searched the forum for Histogram Equalization and could find only references to a Virtualdub plugin. It appears that there is no plugin for Avisynth with this function. I have also glanced through Levels and Tweak descriptions and part of code. It appears that there is no automatic ( I mean without inputting parameters) equalization or matching with another image, facility either builtin or a plugin. I would like to know the correct situation. Tweak further requires input of parameters in Hue, saturation and Intensity format. HDRAGC is probably based on a different concept.
The reason for this querry is I am coding such a plugin and if it is already existing then there is no point in my reinventing the wheel.
Guest
24th September 2005, 03:57
I'm not aware of any Avisynth filters for HE. I have global HE and windowed HE filters for VirtualDub at my web site. They were fun to write (especially the windowed one) but are not terribly useful for everyday video processing.

http://neuron2.net/histogram.html
http://neuron2.net/winhistogram.html

It would not be hard to port these to Avisynth. I consider it significant that nobody ever asked for that.
mg262
24th September 2005, 08:50
Automatic matching with another clip:

http://forum.doom9.org/showthread.php?t=96308

It will of course work on an image, treated as a one frame clip. No equalisation though.
Guest
24th September 2005, 12:34
@mg262

Is the source code available? Your work would be much more useful to the community if you would release source code.
mg262
24th September 2005, 16:46
You are welcome to it if you PM me with an e-mail address. (Cf. my comment to @trevlac in that thread -- Edit:end of this post (http://forum.doom9.org/showthread.php?p=680308#post680308).)
mg262
26th September 2005, 21:36
I've just looked back at the source and it's in better shape than most. It would take me a couple of evenings to comment everything and tidy it up to the point where I would be happy to release it. I don't mind doing that if someone has a concrete use for it. ...

If only the method(s) are wanted, I can document that in the relevant thread to be clearer and more succinct than the source code -- and you are likely to see it much sooner.