Digital Image Compression by Huffman Code

THE STORAGE AND TRANSMISSION OF DIGITAL IMAGES ARE REQUIRED IN MANY APPLICATIONS LIKE OPTICAL SURVEILLANCE, REMOTE SENSING OR EXPERIMENT AUTOMATION. IN SOME APPLICATIONS NO INFORMATION ON PIXEL LEVEL HAS TO BE LOST DURING COMPRESSION AND DECOMPRESSION, EVEN IF THE COMPRESSION FACTOR WILL BE LIMITED BY THIS CONDITION. ONE OF THESE COMPRESSION METHODS IS THE HUFFMAN CODE WITH THE BASIC IDEA THAT NOT ALL QUANTIZATION LEVELS IN AN IMAGE OCCUR EQUALLY OFTEN. HUFFMAN CODE IS A VARIABLE LENGTH CODE IN WHICH SHORTER CODES ARE ASSIGNED TO THE MOST FREQUENTLY OCCURRING LEVELS. THE RESULTING COMPRESSION DEPENDS ON THE TYPE OF INPUT IMAGE. DIFFERENT CORRELATION CASES (NORMAL, LINEAR AND CROSS-DIFFERENCE) HAVE BEEN INVESTIGATED. GOOD RESULTS ARE OBTAINED USING THE LINEAR DIFFERENCE VERSION OF HUFFMAN CODE.

TERMANINI Anselmo;  COMBET Michel;  MORANDI Clelia; 

1995-03-15

CEC

JRC5539

EUR 11475 EN,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC5539,