Declarationproperty PNG_Compression: Integer;
Determines how much time the PNG compressor will spend trying to compress image data when saving a PNG.
Allowed values are from 0 (no compression) to 9 (best compression).
Higher compression values do NOT affect image quality (unlike formats with lossy compression such as JPEG). Choosing a compression setting higher than average delays processing, but often does not result in a significantly smaller file size.
Example// Set best compression
ImageEnView1.IO.Params.PNG_Filter := ioPNG_FILTER_PAETH;
ImageEnView1.IO.Params.PNG_Compression := 9;
// Save PNG