JPEG_DECODE

代码说明：

  本解码器类支持普通jpeg文件格式，这也是目前大多数jpeg文件所采用的格式，此格式主要特点是数据精度为8位，采用Huffman编码的普通DCT帧（不支持扩展串行和递进模式及数学编码）。本解码器类的 IDCT算法采用三种模式，分别是浮点解码、定点整数解码和定点整数MMX优化解码，您可根据具体情况选择。(The decoder class support common JPEG file format, which is currently the most JPEG files in the format and the main characteristics of this format is data for 8-bit precision, using Huffman coding DCT common frame (does not support extended serial and progressive model and arithmetic coding). The decoder of the IDCT algorithm uses three modes, respectively, floating-point decoding, fixed-point integer decoding and fixed-point integer MMX optimization, you can choose according to the specific circumstances.)