jpeg.h

C语言实现的JPEG解码程序 效率比较高

    
// simplejpeg.cpp : Defines the entry point for the console application.
//
//header file
//#include "bmp.h"


//*************************************************************************************
//#include "jpeg.h"
#ifndef __JPEG__
#define __JPEG__


#include "memory.h"
#include "math.h"
#include "stdio.h"
#include "bmp.h"

#pragma pack(1)
#define M_SOF0  0xc0
#define M_DHT   0xc4
#define M_EOI   0xd9
#define M_SOS   0xda
#define M_DQT   0xdb
#define M_DRI   0xdd
#define M_APP0  0xe0

static int Zig_Zag[8][8]={{0,1,5,6,14,15,27,28},
        {2,4,7,13,16,26,29,42},
        {3,8,12,17,25,30,41,43},
        {9,11,18,24,37,40,44,53},
        {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}
       };

#define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */
#define W2 2676 /* 2048*sqrt(2)*cos(2*pi/16) */
#define W3 2408 /* 2048*sqrt(2)*cos(3*pi/16) */
#define W5 1609 /* 2048*sqrt(2)*cos(5*pi/16) */
#define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */
#define W7 565  /* 2048*sqrt(2)*cos(7*pi/16) */


//macro definition
#define WIDTHBYTES(i)    ((i+31)/32*4)//??????????
#define PI 3.1415926535
//define return value of function
#define FUNC_OK 0
#define FUNC_MEMORY_ERROR 1
#define FUNC_FILE_ERROR 2
#define FUNC_FORMAT_ERROR 3


//////////////////////////////////////////////////
//Jpeg functions
BOOL LoadJpegFile(char *BmpFileName);
void showerror(int funcret);
int  InitTag();
void InitTable();
int  Decode();
int  DecodeMCUBlock();
int  HufBlock(BYTE dchufindex,BYTE achufindex);
int  DecodeElement();
void IQtIZzMCUComponent(short flag);
void IQtIZzBlock(short  *s ,int * d,short flag);
void GetYUV(short flag);
void StoreBuffer();
BYTE ReadByte();
void Initialize_Fast_IDCT();
void Fast_IDCT(int * block);
void idctrow(int * blk);
void idctcol(int * blk);
//////////////////////////////////////////////////
//global variable declaration1
struct BITMAPFILEHEADER   bf;
struct BITMAPINFOHEADER   bi;
//HPALETTE           hPalette=NULL;
//HBITMAP            hBitmap=NULL;
char *            hImgData=NULL;
DWORD              NumColors;
DWORD              LineBytes;
DWORD              ImgWidth=0 , ImgHeight=0;
char*             lpPtr;
//////////////////////////////////////////////////
//variables used in jpeg function
short   SampRate_Y_H,SampRate_Y_V;
short   SampRate_U_H,SampRate_U_V;
short   SampRate_V_H,SampRate_V_V;
short   H_YtoU,V_YtoU,H_YtoV,V_YtoV;
short   Y_in_MCU,U_in_MCU,V_in_MCU;
unsigned char   *lpJpegBuf;
unsigned char   *lp;
short   qt_table[3][64];
short   comp_num;
BYTE   comp_index[3];
BYTE      YDcIndex,YAcIndex,UVDcIndex,UVAcIndex;
BYTE   HufTabIndex;
short      *YQtTable,*UQtTable,*VQtTable;
BYTE   And[9]={0,1,3,7,0xf,0x1f,0x3f,0x7f,0xff};
short      code_pos_table[4][16],code_len_table[4][16];
unsigned short code_value_table[4][256];
unsigned short huf_max_value[4][16],huf_min_value[4][16];
short   BitPos,CurByte;
short   rrun,vvalue;
short   MCUBuffer[10*64];
int    QtZzMCUBuffer[10*64];
short   BlockBuffer[64];
short   ycoef,ucoef,vcoef;
BOOL   IntervalFlag;
short   interval=0;
int    Y[4*64],U[4*64],V[4*64];
DWORD      sizei,sizej;
short    restart;
static  long iclip[1024];
static  long *iclp;

#endif // __JENC__//---yk--- add