说明：  霍夫曼编码 是一种瞬时的、唯一可解码的分组编码。 MATLAB源文件，用于图像压缩 ，可添加到MATLAB路径，直接调用！
(Huffman coding is a transient, only the encoding can be decoded packet. MATLAB source files, for image compression, can be added to the MATLAB path, directly call!)