But EWA Mitchell is not sharp enough.......NicolasRobidoux wrote:it's about as sharp as EWA Mitchell, but it has almost no second halo, and it definitely suppresses moire better.
viewtopic.php?f=1&t=20992&start=225#p90392
Search found 188 matches
- 2012-09-23T08:03:37-07:00
- Forum: Users
- Topic: best downsampling method for DSLR photographs
- Replies: 273
- Views: 478323
Re: best downsampling method for DSLR photographs
- 2012-09-23T08:00:31-07:00
- Forum: Users
- Topic: line drawings to test downsizing methods
- Replies: 10
- Views: 14462
Re: line drawings to test downsizing methods
I prefer linear light with EWA lanczos3Sharpest
- 2012-09-20T19:33:17-07:00
- Forum: Users
- Topic: best downsampling method for DSLR photographs
- Replies: 273
- Views: 478323
Re: best downsampling method for DSLR photographs
The moire pattern of the Fly is my second concern.
My first concern is the change in overall brightness (i.e., de-focus my eyes and watch the compound eyes). Yet, unless we have a well-tuned monitor, it is impossible to detect judge whether there is any real brightness change.
My first concern is the change in overall brightness (i.e., de-focus my eyes and watch the compound eyes). Yet, unless we have a well-tuned monitor, it is impossible to detect judge whether there is any real brightness change.
- 2012-09-19T22:34:22-07:00
- Forum: Users
- Topic: best downsampling method for DSLR photographs
- Replies: 273
- Views: 478323
Re: best downsampling method for DSLR photographs
From the zipper on the left, I think Ginseng3 and EWA-LanczosSharp have similar "sharpness", but then from the backpack surface, EWA-LanczosSharp have less "noise". For "Fly", I found something strange. On down-sampling to 403x600, Ginseng3 is making the compound eyes l...
- 2012-09-19T03:54:54-07:00
- Forum: Users
- Topic: best downsampling method for DSLR photographs
- Replies: 273
- Views: 478323
Re: best downsampling method for DSLR photographs
Yup, there are fewer halos; unfortunately, it also reduces the reflection of the nylon fibre vastly. May we use a 2-lobe downsizer with lower sigmoidization value? The backpack photo is a special use-case. EWA Catrom, "Cub-grange" (cubic @ c=0.4846), Lagrange and Lanczos2VerySharp (blur=0....
- 2012-09-17T17:09:57-07:00
- Forum: Users
- Topic: sigmoidized EWA LanczosRadius3 ... and tensor Quadratic
- Replies: 56
- Views: 61687
Re: sigmoidized EWA (-distort resize) LanczosRadius3
Did you resample through linear light or straight sRGB? I did it in linear light. Actually, it is an incorrect description. When downsizing, EWA Lagrange generates "only" a dark "border" around a sharp edge (as in 2-lobe Lanczos and Cubic) but 3-lobe Lanczos generates a dark &qu...
- 2012-09-16T00:58:26-07:00
- Forum: Users
- Topic: sigmoidized EWA LanczosRadius3 ... and tensor Quadratic
- Replies: 56
- Views: 61687
Re: sigmoidized EWA (-distort resize) LanczosRadius3
And some time ago I have tested downsizing of black and white texts with EWA lanczos3, catrom and lagrange. I remember that EWA lagrange produces dark halos more than white halos. Perhaps it's the reason I like it better.NicolasRobidoux wrote:Interesting. Thank you Henry.
- 2012-09-15T09:27:44-07:00
- Forum: Users
- Topic: sigmoidized EWA LanczosRadius3 ... and tensor Quadratic
- Replies: 56
- Views: 61687
Re: sigmoidized EWA (-distort resize) LanczosRadius3
You might mention Lagrange as about on par or perhaps some better (according to henrywho) as catrom. For web-size downsampling of natural photos, EWA Lagrange appears similar to EWA Cubic @c=0.483 ~ 0.485 But for artificial ones like rings_lg_orig.png, EWA Lagrange behaves quite a bit differently t...
- 2012-08-27T20:15:39-07:00
- Forum: Digital Image Processing
- Topic: proper scaling of the Jinc filter for EWA use
- Replies: 234
- Views: 617304
Re: proper scaling of the Jinc filter for EWA use
:shock: Have I missed anything? :shock: if /i "%FILTER%" == "JincJinc2Old" set RESZFT=-filter Lanczos2Sharp if /i "%FILTER%" == "JincJinc3Old" set RESZFT=-filter LanczosSharp if /i "%FILTER%" == "JincJinc4Old" set RESZFT=-define filter:filt...
- 2012-08-23T05:14:13-07:00
- Forum: Bugs
- Topic: Luv colorspace showing errors
- Replies: 4
- Views: 6383
Re: Luv colorspace showing errors
Seems pure LUV roundtrip is okay .... but not if resizing is done under LUV
viewtopic.php?f=3&t=21664
viewtopic.php?f=3&t=21664
- 2012-08-19T08:48:22-07:00
- Forum: Digital Image Processing
- Topic: proper scaling of the Jinc filter for EWA use
- Replies: 234
- Views: 617304
Re: proper scaling of the Jinc filter for EWA use
Probably the same case for Lanczos2SharpNicolasRobidoux wrote:It is exactly the built-in value currently used for LanczosSharp.
- 2012-08-16T02:09:20-07:00
- Forum: Bugs
- Topic: Resizing pictures with sharp B/W lines under LUV
- Replies: 13
- Views: 19370
Re: Resizing pictures with sharp B/W lines under LUV
The brightness should be incorrect because of the incorrect gamma assumption. Still the image should remain gray only. One bug in Q16 compiles is that the image is no longer gray. Another bug in Q16 compiles is having abnormal dots generated. The following sample has a light gray dot at the 6-o-cloc...
- 2012-08-15T21:00:25-07:00
- Forum: Bugs
- Topic: Resizing pictures with sharp B/W lines under LUV
- Replies: 13
- Views: 19370
Re: Resizing pictures with sharp B/W lines under LUV
The rings image is grayscale under IM 6.7.8.3 and higher and not sRGB. I thought the image is "sGray" and so I use "-set colorspace sRGB" (not "-colorspace sRGB") before "-colorspace LUV" and "-colorspace LAB". Is it causing the troubles? It seems t...
- 2012-08-15T18:11:13-07:00
- Forum: Bugs
- Topic: Resizing pictures with sharp B/W lines under LUV
- Replies: 13
- Views: 19370
Re: Resizing pictures with sharp B/W lines under LUV
no, coz the HDRI build (ImageMagick 6.7.6-1) is old and it does not support LUV.fmw42 wrote:Have you tried under HDRI compile to see if it behaves differently there?
- 2012-08-15T17:10:32-07:00
- Forum: Bugs
- Topic: Resizing pictures with sharp B/W lines under LUV
- Replies: 13
- Views: 19370
Re: Resizing pictures with sharp B/W lines under LUV
It seems the resize (and distort resize too) codes are not behaving properly under LUV.magick wrote:This suggests that the conversion to and from LUV is correct.