Reducing the file size of a very large images, without changing the image dimensions

Question

Consider an application handling uploading of potentially very large PNG files.

All uploaded files must be stored to disk for later retrieval. However, the PNG files ca

Answer 1

I know you want to preserve the pixel size, but can you reduce the pixel size and adjust the DPI stored with the image so that the display size is preserved? It depends on what client you'll be using to view the images, but most should observe it. If you are using the images on the web, then you can just set the pixel size of the tag.