Static: Huffman coding Dynamic: Adaptive Huffman 一些概念 压缩指标 • Compress a10MBfile to2MB • Compression ratio =5or5:1 • Space savings =0.8or80% 对称与非对称 • Symmetric compression 对称压缩 –requires same time for encoding and decoding –used for live mode applications (teleconfer...
(compression ratio: " << 1 - ((float)(t.size() / 8) / s.size()) << ")" << endl; } void decoder(string &ans, string &c, const HuffmanTree *htree) { // Decode // timeval start1, end1; // float time_use1=0; // gettimeofday(&start1, NULL); // string packed = ...
PURPOSE:To heighten the compression ratio of a Huffamn code for original image data as keeping picture quality in Huffman encoding. CONSTITUTION:A zero counter part 2 counts the amount of data '0' supplied from a zero data detecting part 1, and supplies a count result to an encoder part 3...
HuffmanCoding
Fractal image compression can be obtained by dividing the original grey level image into unoverlappedblocks depending on a threshold value and the well known techniques of Quadtree decomposition. By usingthreshold value of 0.2 and Huffman coding for encoding and decoding of the image these techniques...
private double compressionRatio; public HuffmanTree(String message) { // Build a map of characters to their frequencies in the message text // Create a HuffmanNode for each character to eventually build tree // Create a PriorityQueue to "sort" the HuffmanNode objects. // Iterate over a set...
In this paper a feed forward Networks with Back propagation Algorithm adopting the method of steepest descent is used to minimize the performance error and a lossless coding technique i.e., Huffman coding to achieve better image compression ratio. The proposed method also includes Cumulative ...
问使用Huffman编码的C压缩库ENHuffman压缩算法是一种基于字符出现频率的编码算法，通过构建Huffman树，将...
Huffman coding Fundamental Data Compression Book2006, Fundamental Data Compression Ida Mengyi Pu Explore book Observation 1. Huffman or Shannon-Fano codes are prefix codes (Section 2.3.3) which are uniquely decodable. 2. There may be a number of Huffman codes, for two reasons: (a) There are ...
This paper discusses a medical application thatcontains a viewer for digital imaging and communications in medicine (DICOM) images as a core module.The proposed application enables scalable wavelet-based compression, retrieval, and decompression ofDICOM medical images and also supports ROI coding/decoding...