simple_jpeg_enc.txt

一个jpeg编码程序

  SYM2 Symbol;  

  Symbol.codeLen = ComputeVLI(value);              //获取编码长度
  Symbol.amplitude = 0;
  if (value >= 0)
  {
   Symbol.amplitude = value;
  }
  else
  {
   Symbol.amplitude = SHORT(pow(2,Symbol.codeLen)-1) + value;  //计算反码
  }

  return Symbol;
 }


 //返回符号的长度
 BYTE ComputeVLI(SHORT val)
 { 
  BYTE binStrLen = 0;
  val = abs(val); 
  //获取二进制码长度   
  if(val == 1)
  {
   binStrLen = 1;  
  }
  else if(val >= 2 && val <= 3)
  {
   binStrLen = 2;
  }
  else if(val >= 4 && val <= 7)
  {
   binStrLen = 3;
  }
  else if(val >= 8 && val <= 15)
  {
   binStrLen = 4;
  }
  else if(val >= 16 && val <= 31)
  {
   binStrLen = 5;
  }
  else if(val >= 32 && val <= 63)
  {
   binStrLen = 6;
  }
  else if(val >= 64 && val <= 127)
  {
   binStrLen = 7;
  }
  else if(val >= 128 && val <= 255)
  {
   binStrLen = 8;
  }
  else if(val >= 256 && val <= 511)
  {
   binStrLen = 9;
  }
  else if(val >= 512 && val <= 1023)
  {
   binStrLen = 10;
  }
  else if(val >= 1024 && val <= 2047)
  {
   binStrLen = 11;
  }

  return binStrLen;
 }

 //********************************************************************
 // 方法名称:BuildVLITable 
 //
 // 方法说明:生成VLI表
 //
 // 参数说明:
 //********************************************************************
 void BuildVLITable(void)
 {
  int i   = 0;

  for (i = 0; i < DC_MAX_QUANTED; ++i)
  {
   pVLITAB[i] = ComputeVLI(i);
  }

  for (i = DC_MIN_QUANTED; i < 0; ++i)
  {
   pVLITAB[i] = ComputeVLI(i);
  }
 }
};

#endif // __JENC__

 


Jpeg.h

typedef struct tagBMBUFINFO
{
    UINT imgWidth;
    UINT imgHeight;
 UINT buffWidth;
 UINT buffHeight;
    WORD BitCount;
    BYTE padSize;    
}BMBUFINFO;

// DCT转换尺寸
static const BYTE DCTSIZE = 8;
// DCT转换块长度
static const BYTE DCTBLOCKSIZE = 64;  

//Huffman码结构
typedef struct tagHUFFCODE
{
 WORD code;  // huffman 码字
 BYTE length;  // 编码长度
 WORD val;   // 码字对应的值
}HUFFCODE;
//AC信号中间符号结构
typedef struct tagACSYM
{
 BYTE zeroLen;  //0行程
 BYTE codeLen;  //幅度编码长度
 SHORT amplitude;//振幅
}ACSYM;

//DC/AC 中间符号2描述结构
typedef struct tagSYM2
{
 SHORT amplitude;//振幅
 BYTE codeLen;  //振幅长度(二进制形式的振幅数据的位数)
}SYM2;

// 存放VLI表
BYTE VLI_TAB[4096];
BYTE* pVLITAB;                        //VLI_TAB的别名,使下标在-2048-2048

// 存放2个量化表
BYTE YQT[DCTBLOCKSIZE]; 
BYTE UVQT[DCTBLOCKSIZE]; 
// 存放2个FDCT变换要求格式的量化表
FLOAT YQT_DCT[DCTBLOCKSIZE];
FLOAT UVQT_DCT[DCTBLOCKSIZE];
//存放4个Huffman表
HUFFCODE STD_DC_Y_HT[12];
HUFFCODE STD_DC_UV_HT[12];
HUFFCODE STD_AC_Y_HT[256];
HUFFCODE STD_AC_UV_HT[256];

static BYTE bytenew=0; // The byte that will be written in the JPG file
static CHAR bytepos=7; //bit position in the byte we write (bytenew)
//should be<=7 and >=0
static USHORT mask[16]={1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8192,16384,32768};

static const DOUBLE aanScaleFactor[8] = {1.0, 1.387039845, 1.306562965, 1.175875602,
1.0, 0.785694958, 0.541196100, 0.275899379};

//量化后DC范围在-2^11 - 2^11 - 1之间,量化后AC范围在-2^10 - 2^10 - 1之间
static const INT AC_MAX_QUANTED = 1023;   //量化后AC的最大值
static const INT AC_MIN_QUANTED = -1024;   //量化后AC的最小值
static const INT DC_MAX_QUANTED = 2047;   //量化后DC的最大值
static const INT DC_MIN_QUANTED = -2048;   //量化后DC的最小值


//标准亮度信号量化模板
const static BYTE std_Y_QT[64] = 
{
 16, 11, 10, 16, 24, 40, 51, 61,
  12, 12, 14, 19, 26, 58, 60, 55,
  14, 13, 16, 24, 40, 57, 69, 56,
  14, 17, 22, 29, 51, 87, 80, 62,
  18, 22, 37, 56, 68, 109,103,77,
  24, 35, 55, 64, 81, 104,113,92,
  49, 64, 78, 87, 103,121,120,101,
  72, 92, 95, 98, 112,100,103,99
};

//标准色差信号量化模板
const static BYTE std_UV_QT[64] = 
{
 17, 18, 24, 47, 99, 99, 99, 99,
  18, 21, 26, 66, 99, 99, 99, 99,
  24, 26, 56, 99, 99, 99, 99, 99,
  47, 66, 99 ,99, 99, 99, 99, 99,
  99, 99, 99, 99, 99, 99, 99, 99,
  99, 99, 99, 99, 99, 99, 99, 99,
  99, 99, 99, 99, 99, 99, 99, 99,
  99, 99, 99, 99, 99, 99, 99, 99
};

//正向 8x8 Z变换表
const static BYTE FZBT[64] =
{
 0, 1, 5, 6, 14,15,27,28,
  2, 4, 7, 13,16,26,29,42,
  3, 8, 12,17,25,30,41,43,
  9, 11,18,24,31,40,44,53,
  10,19,23,32,39,45,52,54,
  20,22,33,38,46,51,55,60,
  21,34,37,47,50,56,59,61,
  35,36,48,49,57,58,62,63 
};

//色彩空间系数常量,依次是411,111,211采样的系数,211采样的2种方式的系数相同
static const FLOAT COLORSPACECOEF[4][3] = {{1,0.25,0.25},{1,1,1},{1,0.5,0.5},{1,0.5,0.5}};
//MCU中各型号分量出现的比率
static const BYTE MCUIndex[4][3] = {{4,1,1},{1,1,1},{2,1,1},{2,1,1}};

// 标准Huffman表 (cf. JPEG standard section K.3) 
static BYTE STD_DC_Y_NRCODES[17]={0,0,1,5,1,1,1,1,1,1,0,0,0,0,0,0,0};
static BYTE STD_DC_Y_VALUES[12]={0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};

static BYTE STD_DC_UV_NRCODES[17]={0,0,3,1,1,1,1,1,1,1,1,1,0,0,0,0,0};
static BYTE STD_DC_UV_VALUES[12]={0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};

static BYTE STD_AC_Y_NRCODES[17]={0,0,2,1,3,3,2,4,3,5,5,4,4,0,0,1,0X7D };
static BYTE STD_AC_Y_VALUES[162]= {
 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
  0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
  0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
  0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
  0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
  0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
  0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
  0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
  0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
  0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
  0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
  0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
  0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
  0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
  0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
  0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
  0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
  0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
  0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
  0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
  0xf9, 0xfa };

 static BYTE STD_AC_UV_NRCODES[17]={0,0,2,1,2,4,4,3,4,7,5,4,4,0,1,2,0X77};
 static BYTE STD_AC_UV_VALUES[162]={
  0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
   0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
   0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
   0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
   0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
   0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
   0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
   0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
   0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
   0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
   0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
   0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
   0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
   0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
   0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
   0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
   0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
   0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
   0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
   0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
   0xf9, 0xfa };  


Jpegformat.h

//文件开始,开始标记为0xFFD8
const static WORD SOITAG = 0xD8FF;

//文件结束,结束标记为0xFFD9
const static WORD EOITAG = 0xD9FF;

//JFIF APP0段结构
#pragma pack(push,1)
typedef struct tagJPEGAPP0
{
 WORD segmentTag;  //APP0段标记，必须为FFE0
 WORD length;    //段长度，一般为16，如果没有缩略图
 CHAR id[5];     //文件标记 "JFIF" + "\0"
 WORD ver;      //文件版本，一般为0101或0102
 BYTE densityUnit; //密度单位，0=无单位 1=点数/英寸 2=点数/厘米
 WORD densityX;   //X轴方向密度,通常写1
 WORD densityY;   //Y轴方向密度,通常写1
 BYTE thp;     //缩略图水平像素数,写0
 BYTE tvp;     //缩略图垂直像素数,写0
}JPEGAPP0;// = {0xE0FF,16,'J','F','I','F',0,0x0101,0,1,1,0,0};
#pragma pack(pop)

//JFIF APPN段结构
#pragma pack(push,1)
typedef struct tagJPEGAPPN
{
 WORD segmentTag;  //APPn段标记，从FFE0 - FFEF n=0-F
 WORD length;    //段长度   
}JPEGAPPN;
#pragma pack(pop)  

//JFIF DQT段结构(8 bits 量化表)
#pragma pack(push,1)
typedef struct tagJPEGDQT_8BITS
{
 WORD segmentTag;  //DQT段标记，必须为0xFFDB
 WORD length;    //段长度,这里是0x4300
 BYTE tableInfo;  //量化表信息
 BYTE table[64];  //量化表(8 bits)
}JPEGDQT_8BITS;
#pragma pack(pop)

//JFIF DQT段结构(8 bits 量化表)
#pragma pack(push,1)
typedef struct tagJPEGDQT_16BITS
{
 WORD segmentTag;  //DQT段标记，必须为0xFFDB
 WORD length;    //段长度，这里是0x8300
 BYTE tableInfo;  //量化表信息
 WORD table[64];   //量化表(16 bits)
}JPEGDQT_16BITS;
#pragma pack(pop)

//JFIF SOF0段结构(真彩)，其余还有SOF1-SOFF
#pragma pack(push,1)
typedef struct tagJPEGSOF0_24BITS
{
 WORD segmentTag;  //SOF段标记，必须为0xFFC0
 WORD length;    //段长度，真彩图为17，灰度图为11
 BYTE precision;  //精度，每个信号分量所用的位数，基本系统为0x08
 WORD height;    //图像高度
 WORD width;     //图像宽度
 BYTE sigNum;   //信号数量，真彩JPEG应该为3，灰度为1
 BYTE YID;     //信号编号，亮度Y
 BYTE HVY;     //采样方式，0-3位是垂直采样，4-7位是水平采样
 BYTE QTY;     //对应量化表号
 BYTE UID;     //信号编号，色差U
 BYTE HVU;     //采样方式，0-3位是垂直采样，4-7位是水平采样
 BYTE QTU;     //对应量化表号
 BYTE VID;     //信号编号，色差V
 BYTE HVV;     //采样方式，0-3位是垂直采样，4-7位是水平采样
 BYTE QTV;     //对应量化表号
}JPEGSOF0_24BITS;// = {0xC0FF,0x0011,8,0,0,3,1,0x11,0,2,0x11,1,3,0x11,1};
#pragma pack(pop)

//JFIF SOF0段结构(灰度)，其余还有SOF1-SOFF
#pragma pack(push,1)
typedef struct tagJPEGSOF0_8BITS
{
 WORD segmentTag;  //SOF段标记，必须为0xFFC0
 WORD length;    //段长度，真彩图为17，灰度图为11
 BYTE precision;  //精度，每个信号分量所用的位数，基本系统为0x08
 WORD height;    //图像高度
 WORD width;     //图像宽度
 BYTE sigNum;   //信号数量，真彩JPEG应该为3，灰度为1
 BYTE YID;     //信号编号，亮度Y
 BYTE HVY;     //采样方式，0-3位是垂直采样，4-7位是水平采样
 BYTE QTY;     //对应量化表号 
}JPEGSOF0_8BITS;// = {0xC0FF,0x000B,8,0,0,1,1,0x11,0};
#pragma pack(pop)

//JFIF DHT段结构
#pragma pack(push,1)
typedef struct tagJPEGDHT
{
 WORD segmentTag;  //DHT段标记，必须为0xFFC4
 WORD length;    //段长度
 BYTE tableInfo;  //表信息，基本系统中 bit0-3 为Huffman表的数量，bit4 为0指DC的Huffman表 为1指AC的Huffman表，bit5-7保留，必须为0
 BYTE huffCode[16];//1-16位的Huffman码字的数量，分别存放在数组[1-16]中
 //BYTE* huffVal;  //依次存放各码字对应的值
}JPEGDHT;
#pragma pack(pop)

// JFIF SOS段结构（真彩）
#pragma pack(push,1)
typedef struct tagJPEGSOS_24BITS
{
 WORD segmentTag;  //SOS段标记，必须为0xFFDA
 WORD length;    //段长度，这里是12
 BYTE sigNum;   //信号分量数，真彩图为0x03,灰度图为0x01
 BYTE YID;     //亮度Y信号ID,这里是1
 BYTE HTY;     //Huffman表号，bit0-3为DC信号的表，bit4-7为AC信号的表
 BYTE UID;     //亮度Y信号ID,这里是2
 BYTE HTU;
 BYTE VID;     //亮度Y信号ID,这里是3
 BYTE HTV;
 BYTE Ss;     //基本系统中为0
 BYTE Se;     //基本系统中为63
 BYTE Bf;     //基本系统中为0
}JPEGSOS_24BITS;// = {0xDAFF,0x000C,3,1,0,2,0x11,3,0x11,0,0x3F,0};
#pragma pack(pop)

// JFIF SOS段结构（灰度）
#pragma pack(push,1)
typedef struct tagJPEGSOS_8BITS
{
 WORD segmentTag;  //SOS段标记，必须为0xFFDA
 WORD length;    //段长度，这里是8
 BYTE sigNum;   //信号分量数，真彩图为0x03,灰度图为0x01
 BYTE YID;     //亮度Y信号ID,这里是1
 BYTE HTY;     //Huffman表号，bit0-3为DC信号的表，bit4-7为AC信号的表  
 BYTE Ss;     //基本系统中为0
 BYTE Se;     //基本系统中为63
 BYTE Bf;     //基本系统中为0
}JPEGSOS_8BITS;// = {0xDAFF,0x0008,1,1,0,0,0x3F,0};
#pragma pack(pop) 

// JFIF COM段结构
#pragma pack(push,1)
typedef struct tagJPEGCOM
{
 WORD segmentTag;  //COM段标记，必须为0xFFFE
 WORD length;    //注释长度
}JPEGCOM;
#pragma pack(pop) 


Main.cpp

#include <iostream>
#include "jenc.h"

using namespace std;

int main(int argc, char* argv[])
{
 if (argc <= 1)
 {
  cout << "please input bmp filename." << endl;
  return 0;
 }

 string fileName = string(argv[1]);
 string outFile = fileName.substr(0,fileName.find_last_of('.'));
 outFile = outFile + ".jpg";

 JEnc enc;
 enc.Invoke(fileName, outFile,100);
 cout << outFile << endl;
 getchar();
 return 0;
}