theotherphil
Improve performance of scale and resize
This library uses the resizing functions from the image crate, which was not written to be particularly performant. A possibly unhelpfully vague answer here is to add some benchmarks for those functions in the image crate and look for ways to improve them.
My prompt for creating this issue was the knowledge that the functions in the image crate for filtering images are far slower than they could be, and that the resizing functions share code with the filtering functions.
This benchmark gives an idea of how much performance the filtering functions in the image crate leave on the table (vs some functions in imageproc that have also not had all that much effort spent on their performance): https://github.com/image-rs/imageproc/blob/master/src/filter/mod.rs#L948
The resizing functions called by this library live here: https://github.com/image-rs/image/blob/master/src/imageops/sample.rs