Lossy/Lossless and Image Compression

Lossy

It is a compressed image and hence the resolution or the quality of the image will not be as good as Lossless image. The concept of ratio is applicable only for lossy images. For example., if JPEG2000, an entry of 30 means that the algorithm will use a compression ratio of 30:1. By default, images are displayed in the Lossy mode.

Lossless

It is a compressed image type that retains original quality. It consumes long duration to transfer file from server over the internet.

Uncompressed

Uncompressed images are the original images without any compression algorithms applied.