Request: Bell Filter

[movmasty]

I sometimes use resize filter in bilinear mode, it reduces noise and artifacts and lets to compress in less size, but it is too blurring.

The Bell filter, as seen eg. in irfanview for pics, has most of the advantages of the bilinear, but with much less blurring,

it is a sort of halfway between bilinear and bicubic.

Since Vdub already inserted the Lanczos i hope that could be done with bell filter too,
really i expected this in the past, since some video article in the net is already considering the Bell filter like the best choice between bilinear and bicubic

[movmasty]

maybe someone released a resize filter with the Bell filter?

[movmasty]

So, no one interested? Neuron, where are you?? Bell filter is cool i tryed it with pics, when a pic is noised, resizing it with bell make miracles, and very sharper than bilinear, while lanczos keeps all noise and difects....

[movmasty]

... :(

[Guest]

Give a reference to the algorithm if you want it implemented. I don't know what it is so how can I code it?

[movmasty]

Thanks for the reply, but im not a technician, just an user, the search for specs and papers would be your duty :o

I read about bell many years ago on a video site, like intermediate solution between bilinear and bicubic, so its a known question, now i'm using it to resize pics in irfanview, i just found some reference in the forum, http://forum.doom9.org/showthread.php?p=178953#post178953

But i see many new resize filters in MkvMagic, there is B-spline, that should be a bicubic but soft like bilinear as i see with pics in irfanview, more precise i think,

there is not the bell, but there are some that i dont know, maybe updated version of the bell?

try to ask to the Mkv guys, the resize part of Vdub is a little outdated.

[foxyshadis]

The bell filter in my experience is nearly indistiguishable from bilinear or gauss. I'm almost certain that any intermediate effect you're looking for can be made from tweaking gauss(p=) or bicubic(b=,c=). There's no need for avisynth to collect all the different resize algorithms out there, just testing with imagemagick should show how marginal the differences between most are.

[movmasty]

The bell filter in my experience is nearly indistiguishable from bilinear or gauss. I'm almost certain that any intermediate effect you're looking for can be made from tweaking gauss(p=) or bicubic(b=,c=). There's no need for avisynth to collect all the different resize algorithms out there, just testing with imagemagick should show how marginal the differences between most are.
Dont agree, i tested a lot with pics and Bell is definitively very sharper than bilinear, about bilinear we could say that is a bad resizing method because changes all the apparence of pictures, and if i need an hard softing filter i go with B-spline

Bell on its side removes noise and artefacts, while bicubic keeps all them,
thus if you need a filter that isnt bicubic, you can use Bell, bilinear would become unessential, it is a totally datated filter, and bell isnt the last arrived to collect in resizing, it is a main filter.

i'm talking about Virtual dub and its presets, didnt test avisynt bicubic under 0.60, but i dont see substanzial differences between 0.60 and 0.75 as well,
really avisynth filtering is better than virtual dub, but im not using avisynt actually

[Guest]

Thanks for the reply, but im not a technician, just an user, the search for specs and papers would be your duty :o Guess what, pal. I'm also not a technician, nor am I your indentured servant.

[movmasty]

nor am I your indentured servant.
Wait, never intended this.

I thought that requests were legitimate on the forum.

[gurkan]

the search for specs and papers would be your duty

An excellent way to tick somebody off.

You might find this an interesting read:
http://forum.doom9.org/showthread.php?t=52597