Image compression [2]

Vicente González Ruiz

January 1, 2020

Contents

1 Image redundancy
2 Data flow [3]
3 Lossless compressors
4 Lossy compressors
5 Lossy-to-lossless compressors
6 Multiresolution
7 Codecs
References

1 Image redundancy

  1. Pixel-wise analysis shows redundancy.

2 Data flow [3]

PCM   +---------+        +---------+ PCM  
----->| Encoder |------->| Decoder |----->  
image +---------+ stream +---------+ image’  
 
              image != image’  
                (usually)

3 Lossless compressors

  1. Most of them based on differential coding and entropy coding.

4 Lossy compressors

  1. Fundamentaly, based on image transformations, scalar quantization and entropy coding.

5 Lossy-to-lossless compressors

  1. Similar to lossy but using embbeded quantization.

6 Multiresolution

See pyramids and wavelets.

7 Codecs

  1. LOCO.
  2. JPEG.
  3. JPEG2000.
  4. PNG.

References

[1]   M. Nelson and J. Gailly. The Data Compression Book. M&T Books, 1996.

[2]   M. Rabbani and P. W. Jones. Digital Image Compression Techniques. SPIE Opt. Eng. Press, Bellingham, Washington, 1991.

[3]   Khalid Sayood. Introduction to data compression. Morgan Kaufmann, 2017.

[4]   Marcelo J Weinberger, Gadiel Seroussi, and Guillermo Sapiro. LOCO-I: A low complexity, context-based, lossless image compression algorithm. In Data Compression Conference, 1996. DCC’96. Proceedings, pages 140–149. IEEE, 1996.