Re: Resize algorithm implemented in GDI

4N wrote:
Hi,
does someone know what resize algorithm stretchBlt (using HALFTONE option) uses to shrink images?
I used every known interpolant filter I know in the spacial domain and none of them reaches its sharpness so I'm starting to think it's a filter working in the frequency domain...


It looks like a trivial nearest neighbour algorithm (it doesn't increase number of colors in the resized image). It explains it sharpness as well as it's low quality (take any 256 color image and resize it to see how really terrible this algorithm is).

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Grzegorz Wróbel
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