Many
image file formats compress image data to reduce file size. Lossless compression
preserves all image data without removing detail; lossy compression
removes image data and loses some detail.
The following are commonly used compression techniques:
- RLE (Run Length Encoding)
-
Lossless compression technique that compresses the transparent
portions of each layer in images with multiple layers containing transparency.
- LZW (Lemple-Zif-Welch)
-
Lossless compression that provides the best results in compressing
images that contain large areas of single color.
- JPEG
-
Lossy compression that provides the best results with photographs.
- CCITT
-
A family of lossless compression techniques for black-and-white
images.
- ZIP
-
Lossless compression technique that is most effective for
images that contain large areas of a single color.