Cubic resampling

[Tiles]

Here my try to get close to cubic resampling. The problem is to resize with interpolation. Overlay can just resize without interpolation. And so a resized picture has the same sharp borders as the source.



Not what i need. I need cubic resizing to achieve soft edges. Here what Gimp produces with cubic resizing:



And here what my example app can do at the moment by cubic resampling :



Better said, this is just a snapshot. I have setup the stuff so that you can adjust how often it samples and which pixels in what range to test.

Pretty close to what i want. But slow as hell. And i am still in trouble how the resample steps and the range of the surrounding pixels are connected to resizing.

Maybe somebody has a faster and better method. But keep in mind that i need colours too. So no good idea to use just one colour channel for calculation

Attached file is 16 Kb

[LazyCoder]

A faster better method? Just resize a HWA active object.

[Tiles]

Haha. In the Build 248?

Also keep in mind that i have to load the source and save the result then

[Tiles]

Still slow, but 1/3 faster than my upper method. Resamples a 1024x1024 picture in 17 seconds where my first file needs 25. So i thought it may be worth to release it.

18 Kb

[Sphax]

nice

[Patrick]

Whats the purpose?

[Dynamite]

Cubic resampling

[Tiles]

The purpose is to fake cubic resizing. Means to soften an image. With no black border as you get when you use soften or blur by the Image Manipulator Object. And with more control.

Think of creating a heightmap by perlin noise. Here you create three pictures with different size. Then you resize the two smaller ones to the size of the biggest. And combine the noise of them then. For that you need something to soften the pictures. Else you would have a cubic landscape. And the most common method is Cubic resizing. Because it softens the picture when resizing it.

Or simply think of a borderfree blur method

Unfortunately none of the available image extensions that are able to load and save can do cubic resizing. I was also not able to understand how cubic resizing works. Haven`t seen some of the math symbols in the formulas before. And so i have to fake it

I think i found the fastest method now by the way. 14 Seconds for resampling a 1024x1024 pixture now

17 Kb