Resize limitations, Lanczos option For Rawtherapee 5.4 on Windows 7

(Jim Plaxco) #1

For Rawtherapee 5.4 on Windows 7, on the page it says
“Lanczos is the default method… Use it to resize by any amount.” This appears to be wrong since when I try to resize, whether by specifying scale, width, or height, I can go no larger than 4x the image. In this case the source image is a 1080 x 720 pixels tiff file.
The scale slider tops out at 4.0 and if I specify a pixel width larger than 4320(1080*4), when I tab out of the width field, no matter what value larger than 4320 I put in it reverts down to 4320. Also with a value of 4320, the plus button becomes disabled. Is this really the way Rawtherapee’s resize function is supposed to work?

Resize options used are
Applies to: Full Image
Method: Lanczos
Specify: width

Also, resize was applied as the only action to be taken.


(Morgan Hardwood) #2

This limit has nothing to do with Lanczos; it is tied to the “Scale” and was raised from 4x to 16x for RawTherapee 5.5.

(Jim Plaxco) #3

Hello Morgan,
Thanks for the info. I suggest a rewrite of the Resize documentation since the “resize by ANY amount” statement is paired with the description of the Lanczos resize option. I saw nothing in the doc that indicated a resize ceiling. Hopefully this can be updated for the next version of the doc.

(Morgan Hardwood) #4


(Jim Plaxco) #5

Wonderful. Thanks.