Stairstep interpolation

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In image processing, stairstep interpolation is a general method for interpolating the pixels after enlarging an image. The key idea is to interpolate multiple times in small increments using any interpolation algorithm that is better than nearest-neighbor interpolation, such as bilinear interpolation, and bicubic interpolation. A common scenario is to interpolate an image by using a bicubic interpolation which increases the image size by no more than 10% (110% of the original size) at a time until the desired size is reached.

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A comparison of stairstep and direct bilinear image scaling, using multiple 10% steps versus one 100% step Comparison stairstep and direct bilinear image scaling.png
A comparison of stairstep and direct bilinear image scaling, using multiple 10% steps versus one 100% step

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