PNG images from any source will work in PNG Crush.
Your second question is misguided; PNG is not a tool to do the compressing, png is simply a file format with which you can compress the data in an image. How well a given png file is compressed depends on the tool the image is saved from.
The recompressed images are still normal PNG images, just with the data rearranged more compactly.
Your second question is misguided; PNG is not a tool to do the compressing, png is simply a file format with which you can compress the data in an image. How well a given png file is compressed depends on the tool the image is saved from.
The recompressed images are still normal PNG images, just with the data rearranged more compactly.