image_compression

代码说明：

   Huffman coding uses a specific method for choosing the representation for each symbol, resulting in a prefix code (sometimes called prefix-free codes , that is, the bit string representing some particular symbol is never a prefix of the bit string representing any other symbol). Huffman coding is such a widespread method for creating prefix codes that the term Huffman code is widely used as a synonym for prefix code even when such a code is not produced by Huffman s algorithm.