sharpening like LanczosResize without resizing?

[Heini011]

hi,

i encode sharp anamorphic video material only with crop and MSharpen for slightly sharpening the bigger outlines. i use xvid and the h263 matrix. resizing is done within matroska.

that works great for good video-material, but i still need a good filter for sharpening older materials without amplify noise like UnFilter and with a more adjustable sharpening effect as asharp.

so until today i use for such material MSharpen and LanczosResize.

so, have someone ideas for a sharpening effect like LanczosResize but without resizing ?

greetings, Heini011.

[Manao]

Using the lanczos algorithm without resizing wouldn't change the picture, because lanczos doesn't sharpen, it only resizes.

[Heini011]

>Using the lanczos algorithm without resizing wouldn't change
>the picture

not necessary: LanczosResize(2*x,2*y).LanczosResize(x,y) ;-)

but i look for a good sharpening filter, not a resizer...

greetings.

[Manao]

LanczosResize(2*x,2*y).LanczosResize(x,y)Indeed, but it's a theorically a blur ( well not exactly, but almost ), not a sharpen, and anyway visually, you can't spot any differences with or without the lanczoss.

I don't know well the different sharpeners for avisynth, so I won't be able to help you.

[jorel]

you use in your tests the "elite"(as i call)of the sharpening filters:
Asharp(MarcFD),Unfilter(trbarry),Msharpen(neuron2)...i can't think(and don't know) better filters for that kind of job!
about LanczosResize:
"...with high values of c about 0.6 ... 0.75 which produces quite strong sharpening.
It usually offers better quality (fewer artifacts) and a sharp image."
don't have a way to use without change the source-->target size?

[MfA]

Lanczos sharpens because it rings, just like the sharpening filters jorel proposed.

[Didée]

Originally posted by MfA
Lanczos sharpens because it rings
To ring, or not to ring (http://forum.doom9.org/showthread.php?s=&postid=532809#post532809), that's a question.

[Cyberman]

It´s not AviSynth, but I found that MSU´s smart sharpen is quite good.
It enhances the picture without blurring it. Of course, any dominant noise will be "sharpened" as well.

http://compression.ru/video/smart_sharpen/index_en.html

[jorel]

the pictures in the page are great but how i use this filter in .avs script? :confused:

[Didée]

Also it has a leftover tendency to give that subliminal "fat" look of unsharp masking.
If you knew about Limited's latest parameter - contrast enhancement free of ringing, leaving noise almost alone ... added one day before the curtains fell down.
Hmh, but even the readme was almost finished. Perhaps I should dig it out and post it as-is. After all, I promised a thread about it ...

Check back later this week.

[Paced]

Originally posted by jorel
the pictures in the page are great but how i use this filter in .avs script? :confused:

You could always apply the filter in VirtualDub, then frameserve it to an Avi file (filename.vdr.avi), then use AviSynth to frameserve the frameserved file - AviSource("filename.vdr.avi") Did that make sense? :D

[Boulder]

Avisynth is able to use VirtualDub plugins itself:

(from the Avisynth docs)


LoadVirtualDubPlugin ("filename", "filtername", preroll)

This loads a plugin written for VirtualDub. "filename" is the name of the .vdf file. After calling this function, the filter will be known as "filtername" in avisynth. VirtualDub filters only supports RGB32. If the video happens to be in RGB24-format, then you must use ConvertToRGB32 (ConvertToRGB won't suffice).

Some filters output depends on previous frames; for those preroll should be set to at least the number of frames the filter needs to pre-process to fill its buffers and/or updates its internal variables.

[Piper]

@Cyberman:

http://compression.ru/video/smart_sharpen/index_en.html

Thanks for the post, I'm always looking for new (undiscovered) filters like this as well.

The pictures on the site look quite good, though after trying it I would suggest using this filter on only very clean sources. On my own test analogue capture, the resulting output does appear sharper, but it also has the "appearance" of introducing noise - enhancing what noise is still there. This effect tends to defeat any denoising filters I may have run prior to it - at least in my books anyway. I used the "small overall" setting which from the looks of things is the most conservative setting. Perhaps I'll experiment more with the "borders" preset when I get a chance.

My initial impressin is this filter may work best with dvd sources - that is if you can stand the wait. Did anyone mention how slow it is? ;)

[Cyberman]

Originally posted by Didée
Also it has a leftover tendency to give that subliminal "fat" look of unsharp masking.

So it´s that filter that produces this horrible effect? I always thought it´s the fault of the source alone. (The source I´m talking about IS horrible already, so the filter can´t be blamed that much.)
Do you know any way to get rid of that? Using (VDubs) Temporal Smoother helps, but also eliminates detail.

--

Yes, the filter enhances noise as well - but it´s far more selective than, for example, VDub´s general "sharpen" filter.

I like to throw the Smart Sharpen in after some serious smoothing(usually reducing detail), it does enhance contrast quite well, making a blurry image almost clear.

[jorel]

Boulder, can you post an .avs to use LoadVirtualDubPlugin (a "how to") please? :o thanks!

[Malevolent]

I'm not Boulder, but this works ;)

Make an .avsi file in your Avisynth plugins dir & insert the following in it:

LoadVirtualdubPlugin("Virtualdub plugins path\PluginName","PluginNameYouWantToUseInScript")
LoadPlugin("Path to LoadPluginEX.dll - can't be in Avisynth plugins dir\LoadPluginEX.dll")
(obviously you need LoadPluginEX.DLL, get it here: http://forum.doom9.org/showthread.php?s=&threadid=57875)

Then just open your file in Virtualdub & set the filter the way you want.
Save processing settings & open the created .vcf.
in the pluginName line, copy the part in parenthesis & paste it in your script like this:

Whateversource("wherever\whatever.xxx")
ConvertToRGB32()
PluginNameYouWantToUseInScript(data from .vcf)