gdImageScale() with floating-point interpolation method looses top row and left column

Issue #93 new
Chris Reuter created an issue

The resulting image is shifted left and up, with the right and bottom rows filled with apparently correct data.

I'll look into it sometime next week and try to have a reproduction and fix available then.

Comments (3)

  1. Pierre Joye

    great, thanks!

    Btw, like access to the repo? Your patches are very good and I would love to see you on board :)

  2. Chris Reuter reporter

    Sure, that's be great.

    Also, can you email me? I'm <chris(at)blit.ca>. I'd like to explain my goals and make sure they're in sync with yours.

  3. Chris Reuter reporter

    This bug seems to be a quirk in the algorithm. Basically, it's resampling from the left edge of the pixel rather than the center (pixels have a width and height when you're using continuous functions) which causes the shift. Fixing it is non-trivial, so I'm going to put it off for now.

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