专利名称：Method and apparatus for video
compression using block and wavelettechniques
发明人：Peter N. Graffagnino申请号：US08/247006申请日：19940519公开号：US06031937A公开日：20000229
摘要：A method and apparatus are disclosed for symmetrically compressing anddecompressing video information in real time by coupling block and wavelet techniques.In the compression pipeline, the image is divided into blocks comprising 2.sup.k ×2.sup.kpixels (in the preferred embodiment, k=1). The average color of each block is computed.The system computes an average luminance for each block and differential luminances ofeach pixel of the plurality of pixels of each block. A first plurality of frequency details ofeach block are determined by Haar transforming the differential luminances. The systemcomputes an average color difference between each block and the preceding block, andquantizes the average color difference and the first plurality of frequency details usingLloyd-Max quantization. In an alternate embodiment, skip codes are generated forblocks having the same quantized average color difference and second plurality offrequency details. The quantized average color difference and a second plurality offrequency details are encoded using variable length codes. The system employs lookuptables to decompress the compressed image and to format output pixels. The output ofthe compression pipeline containing variable length codes is decoded into fixed-length
codes, which are then decoded using a first lookup table into three device-independentcomponents that represent each block. The three components index a second lookuptable containing precomputed RGB values that include precomputed display dependentformatting to produce the output image. In the alternate embodiment, skip codescontained in the output of the variable length decoder are decoded.
申请人：NEXT SOFTWARE, INC.
代理机构：Hecker & Harriman
更多信息请下载全文后查看
因篇幅问题不能全部显示，请点此查看更多更全内容