Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion.

Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules.

 

Go Back   Doom9's Forum > General > Newbies

Reply
 
Thread Tools Search this Thread Display Modes
Old 19th July 2008, 20:32   #1  |  Link
php111
Guest
 
Posts: n/a
What is sharper LanczosResize, Blackman or Lanczos4?

Hi,

What is sharper and a better resizer?

1.) BlackmanResize

2.) LanczosResize

3.) Lanczos4Resize
  Reply With Quote
Old 19th July 2008, 22:34   #2  |  Link
Ranguvar
Registered User
 
Ranguvar's Avatar
 
Join Date: Feb 2007
Location: ::1
Posts: 1,236
Try and see!!

I would also try the Spline resizers (Spline16, Spline36, Spline64).
Ranguvar is offline   Reply With Quote
Old 20th July 2008, 00:14   #3  |  Link
Zwitterion
Registered User
 
Join Date: May 2008
Posts: 80
from soft to sharp (according to my experience):

Bilinear
Bicubic(b=1./3, c=1./3)
Spline16
Bicubic(b=0, c=0.75)
Spline36
Blackman(taps=4)
Spline64
Lanczos3
Lanczos4

However, sharper is not always 'better', as ringing increases too. I wouldn't use anything sharpen than Spline36Resize.
Zwitterion is offline   Reply With Quote
Old 20th July 2008, 00:44   #4  |  Link
Ranguvar
Registered User
 
Ranguvar's Avatar
 
Join Date: Feb 2007
Location: ::1
Posts: 1,236
I saw a post in the Spline thread with a comparison to Lanczos4... Spline36 seems to be slightly sharper and has slightly less ringing than Lanczos4.

And I believe Blackman can get even sharper than Spline...

Again, the best way is to test and see for yourself.
Ranguvar is offline   Reply With Quote
Old 20th July 2008, 00:47   #5  |  Link
php111
Guest
 
Posts: n/a
Thank you everyone for the replies.
  Reply With Quote
Old 20th July 2008, 01:12   #6  |  Link
Avenger007
Bruce Wayne
 
Join Date: Dec 2007
Posts: 283
If you want to try an experiment...

Code:
FUNCTION Focus(clip input, int clp_width, int clp_height)
{
  # May help some edge blurred sources by defining the edges
  ssx = 3.5
  ssy = 3.5
  
  # Supersize the clip ensuring its mod16
  xx_ss2 = int(clp_width * ssx / 16 + 0.5) * 16 
  yy_ss2 = int(clp_height * ssy / 16 + 0.5) * 16 
  input  = input.LanczosResize(xx_ss2,yy_ss2)
  
  # apply our transfors to the edges (blur, warpsharp (only to luma), and xsharpen)
  input = input.removegrain(20)
  input = input.awarpsharp(depth=10, thresh=0.5, blurlevel=2, cm=0)
  input = input.xsharpen(255,255)
  
  # return the clip in its original size, this will just have enhanced edges
  RETURN input.Lanczos4Resize(clp_width,clp_height).RemoveGrain(mode=1)
}
In the Focus(...) function of MC_Spuds, try different resizers and compare their sharpness.
The image is supersampled by upscaling to 3.5x the original size and sharpened, then downscaled to the original size.

Performing this experiment with Lanczos vs Spline shows a noticeable difference, with Lanczos being sharper than Spline.
However, I use Spline64 because it's still sharp and easier to compress by the encoder.

Last edited by Avenger007; 20th July 2008 at 01:24.
Avenger007 is offline   Reply With Quote
Old 20th July 2008, 09:14   #7  |  Link
backtohell
Registered User
 
Join Date: Aug 2007
Posts: 12
i usually prefer slightly more sharpness in my videos so my choice is either Lanczos4 or Spline36, but never heard of Blackman?
backtohell is offline   Reply With Quote
Old 20th July 2008, 09:40   #8  |  Link
Gavino
Avisynth language lover
 
Join Date: Dec 2007
Location: Spain
Posts: 3,377
Quote:
Originally Posted by backtohell View Post
i usually prefer slightly more sharpness in my videos so my choice is either Lanczos4 or Spline36, but never heard of Blackman?
BlackmanResize is available in Avisynth v2.58. To quote from the documentation:
Quote:
BlackmanResize is a modification of LanczosResize that has better control of ringing artifacts for high numbers of taps.
(taps equates to the 3 or 4 in Lanczos3, Lanczos4 and the default for LanczosResize is taps=4).
Gavino is offline   Reply With Quote
Old 20th July 2008, 14:41   #9  |  Link
backtohell
Registered User
 
Join Date: Aug 2007
Posts: 12
Thanks Gavino for the details on BlackmanResize

will give a shot
backtohell is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 01:28.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.