Dear IrfanView Community!
I would like to ask if there is any Bicubic resample filter plugin for IrfanView, because as I noticed IrfanView's (4.25) Lanczos filter is worse when downsizing images (other IV filters [Bell, B-Spline etc.] or simple resize even worse). I've attached two images as comparison about a picture showing block of flats. blocks_bicubic.png (on the left) was downscaled by Photoshop, blocks_lanczos.png (on the right) with IV's Lanczos filter. I'll talk about the third (blocks_imagemagick.png) attachment later. There is no difference at first sight, but try to look more carefully. Lanczos filter causes some sharpness loss at edges. The best way to see the difference is to place them into Photoshop (or GIMP or any software that supports layers) over each other, then start turning the upper layer on/off focusing on the sharp edges. You'll see the difference.
This third image was created using ImageMagick (IMDisplay under Windows). ImageMagick produces the same image as Photoshop, so it must have Bicubic method of resizing (as mentioned in the manual):
The original image was 461x352 (was downsized to 320x244).
Thanks in advance
stringZ
I would like to ask if there is any Bicubic resample filter plugin for IrfanView, because as I noticed IrfanView's (4.25) Lanczos filter is worse when downsizing images (other IV filters [Bell, B-Spline etc.] or simple resize even worse). I've attached two images as comparison about a picture showing block of flats. blocks_bicubic.png (on the left) was downscaled by Photoshop, blocks_lanczos.png (on the right) with IV's Lanczos filter. I'll talk about the third (blocks_imagemagick.png) attachment later. There is no difference at first sight, but try to look more carefully. Lanczos filter causes some sharpness loss at edges. The best way to see the difference is to place them into Photoshop (or GIMP or any software that supports layers) over each other, then start turning the upper layer on/off focusing on the sharp edges. You'll see the difference.
This third image was created using ImageMagick (IMDisplay under Windows). ImageMagick produces the same image as Photoshop, so it must have Bicubic method of resizing (as mentioned in the manual):
The original image was 461x352 (was downsized to 320x244).
Thanks in advance
stringZ
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