View Single Post
Old 1st November 2012, 17:51   #5  |  Link
wonkey_monkey
Formerly davidh*****
 
wonkey_monkey's Avatar
 
Join Date: Jan 2004
Posts: 2,493
Quote:
Originally Posted by ajp_anton View Post
Am I the only one who finds this interesting?
Apparently

Quote:
Feature requests:
- Ability to choose the color of the padding outside the input image
This is probably best left outside of xyremap's remit. The alpha channel is available so you can comp in a different background with overlay.

Quote:
extend the existing border pixels. The bicubic interpolation is making my stretched edges dark.
This can be done either by stacking multiple versions of your input together before remapping (or padding with background colour), then using the % (modulo) operator to constrain the input pixels to within the "real" borders. Or you could try adding:

Code:
... 0.5 max w 0.5 - min
... 0.5 max h 0.5 - min
to your x and y expressions respectively. This may or may not solve it though - I can't test it properly because I've just discovered a bug in the interpolation function that seems to be messing up levels.

Quote:
- Boolean to make x and y go from 0 to 1 so I don't have to divide by u and v.
Rather than a bool, how about two new parameters, a and b, for these values?

Quote:
- Is it possible to make the function go the other direction, map input pixels to the output image instead?
What happens if two input pixels map to the same output pixel? Also bicubic interpolation that way around would be tricky (if not impossible).



TL;DR: there is a bug in the interpolator that I need to fix which is producing slightly wrong pixel values.

David

Last edited by wonkey_monkey; 1st November 2012 at 18:05.
wonkey_monkey is offline   Reply With Quote