Versions of images in Wordpress

Write an algorithm that
will allow you to label old photos in
low resolution on the same, but in
the best and the biggest (original) compress. For example, if we have
photo 123.jpg with permission
4000х3000 and compressed by WordPress
icons 123-150х150.jpg average
123-300x225.jpg and large
123-700x550.jpg then you need small
replace with the size of 480, 720 on medium, large at 1024. And the originals
replace 1920. All this with
the save file name.

So
addresses two problems at once
- improving the quality of the photo on the website
and space saving on the server (there
lots of original pics in huge resolution).
If it's too hard, then just
to label all versions of a single
same file, and the original and
vordpressovskih options in the photo with
1024.

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