目录
背景
一、BMP图片讲解：
二、代码：
背景
1、主要记录下BMP图片的功能，里面包括jpeg格式图片转bmp格式的图片，还有bmp图片的缩放，因为bmp格式的图片一般都很大。
2、网上搜的代码，好多的代码都有依赖，有些是依赖libjpeg.dll，有些是boost，有些是opencv，后面废了不少力气终于找到没有依赖的，太爱了，直接上代码了。
一、BMP图片讲解：
1、BMP（Bitmap）是一种常见的图像文件格式，它是一种无损压缩的图像格式，也就是说，它不会丢失图像的任何细节信息。BMP文件可以存储黑白、灰度或彩色图像，并且可以支持多种位深度和分辨率。
2、BMP图片格式：
- BMP格式的文件通常包含一个文件头和一个位图信息头。
文件头包含了文件类型、文件大小、保留字、位图数据偏移量等信息；
位图信息头则包括了图像的宽度、高度、颜色位数、压缩方式、颜色表等信息。
在图像数据中，每个像素都被表示为一组二进制数，其中每个数表示一个颜色分量，如红色、绿色和蓝色。
（1）文件头：bitmap file header
BITMAPFILEHEADER是位图文件头的结构体，用于描述位图文件的格式和属性。
它通常位于位图文件的开头，其长度为14个字节，包含以下字段：
BITMAPFILEHEADER结构体的定义如下：
typedef struct tagBITMAPFILEHEADER {
WORD bfType;//文件类型，必须为"BM"，占用2个字节
DWORD bfSize;//文件大小，以字节为单位，占用4个字节
WORD bfReserved1;//bfReserved1和bfReserved2：保留字段，占用各2个字节，通常设置为0。
WORD bfReserved2;
DWORD bfOffBits;//bfOffBits：位图数据的偏移量，即位图文件头和位图信息头之后的字节数，占用4个字节。
} BITMAPFILEHEADER;
其中，WORD和DWORD分别表示2个字节和4个字节的无符号整数类型。
（2）位图信息头 ： bitmap info header
BITMAPINFOHEADER是Windows中用于描述位图文件头信息的结构体。
它包含了位图的宽度、高度、颜色位深度等信息，用于解析和显示位图文件。
BITMAPINFOHEADER结构体的定义如下：
typedef struct tagBITMAPINFOHEADER {
DWORD biSize;//结构体的大小，以字节为单位，必须为40。
LONG biWidth;//位图的宽度，以像素为单位。
LONG biHeight;//位图的高度，以像素为单位。如果值为正数，则表示位图是从上到下的；如果值为负数，则表示位图是从下到上的。
WORD biPlanes;//目标设备的位平面数，必须为1
WORD biBitCount;//每个像素的位数，可以是1、4、8、16、24或32。
DWORD biCompression;//指定位图压缩类型。常用的有BI_RGB、BI_RLE8和BI_RLE4。
DWORD biSizeImage;//位图数据的大小，以字节为单位。
LONG biXPelsPerMeter;//目标设备水平方向上每米像素数。
LONG biYPelsPerMeter;//目标设备垂直方向上每米像素数。
DWORD biClrUsed;//位图实际使用的颜色表中的颜色数。
DWORD biClrImportant;//对图像显示有重要影响的颜色索引数。
} BITMAPINFOHEADER, *PBITMAPINFOHEADER;
BITMAPINFOHEADER结构体是位图文件格式中重要的一部分，通过解析这些信息，可以正确地显示和处理位图文件。
二、代码：
1、头文件：文章来源：https://www.toymoban.com/news/detail-766698.html
/*
* @Description: BMP图片的功能
* @Author: Ivy
* @Date: 2022-04-25 09:34:43
* @LastEditTime: 2023-02-24 11:28:29
* @LastEditors: XTZJ-2022OQEHLZ
*/
#pragma once
#include "SingleTon.h"
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string>
#include <windows.h>
#include <iostream>
#include <memory>
using namespace std;
#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) */
//*************************************************************************************
typedef char CHAR;
typedef short SHORT;
typedef long LONG;
typedef unsigned long DWORD;
typedef int BOOL;
typedef unsigned char BYTE;
typedef unsigned short WORD;
typedef int HFILE;
typedef CHAR *LPSTR, *PSTR;
#define FALSE 0
#define TRUE 1
//macro definitio
#define WIDTHBYTES(i) ((i+31)/32*4)
#define PI 3.1415926535
#define FUNC_OK 0
#define FUNC_MEMORY_ERROR 1
#define FUNC_FILE_ERROR 2
#define FUNC_FORMAT_ERROR 3
class CBitmap : public SingleTon<CBitmap>
{
friend class SingleTon<CBitmap>;
public:
CBitmap(void);
virtual ~CBitmap(void);
public:
bool Jpeg2Bmp(const char* pszSrc, int nSrcLength, unsigned char** pszDst, unsigned int& nDstLength);
private:
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);
string getModulePath();
bool BmpZoom(BITMAPFILEHEADER head, BITMAPINFOHEADER info, unsigned char** pszSrc, unsigned int nSrcLength, unsigned char** pszDst, unsigned int& nDstLength);
private:
//global variable declaration
//char * hImgData = NULL;
//std::shared_ptr<char *> hImgData;
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 = NULL;
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;
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;
};
#define Bitmap CBitmap::getInstance()2、源文件：文章来源地址https://www.toymoban.com/news/detail-766698.html
#include "Jpeg2Bmp.h"
#pragma pack(1)
/* constants for the biCompression field */
#define BI_RGB 0L
#define BI_RLE8 1L
#define BI_RLE4 2L
#define BI_BITFIELDS 3L
static long iclip[1024];
static long *iclp;
BYTE And[9] = { 0, 1, 3, 7, 0xf, 0x1f, 0x3f, 0x7f, 0xff };
#define OLD_BMP_PATH "\\oldBmp.bmp"
#define NEW_BMP_PATH "\\newBmp.bmp"
CBitmap::CBitmap(void)
{
}
CBitmap::~CBitmap(void)
{
}
void CBitmap::GetYUV(short flag)
{
short H, VV;
short i, j, k, h;
int *buf;
int *pQtZzMCU;
buf = Y;
pQtZzMCU = QtZzMCUBuffer;
switch (flag) {
case 0:
H = SampRate_Y_H;
VV = SampRate_Y_V;
buf = Y;
pQtZzMCU = QtZzMCUBuffer;
break;
case 1:
H = SampRate_U_H;
VV = SampRate_U_V;
buf = U;
pQtZzMCU = QtZzMCUBuffer + Y_in_MCU * 64;
break;
case 2:
H = SampRate_V_H;
VV = SampRate_V_V;
buf = V;
pQtZzMCU = QtZzMCUBuffer + (Y_in_MCU + U_in_MCU) * 64;
break;
}
for (i = 0; i < VV; i++)
for (j = 0; j < H; j++)
for (k = 0; k < 8; k++)
for (h = 0; h < 8; h++)
buf[(i * 8 + k)*SampRate_Y_H * 8 + j * 8 + h] = *pQtZzMCU++;
}
void CBitmap::StoreBuffer()
{
short i, j;
unsigned char *lpbmp;
unsigned char R, G, B;
int y, u, v, rr, gg, bb;
for (i = 0; i < SampRate_Y_V * 8; i++) {
if ((sizei + i) < ImgHeight) {
lpbmp = ((unsigned char *)lpPtr + (DWORD)(ImgHeight - sizei - i - 1)*LineBytes + sizej * 3);
for (j = 0; j < SampRate_Y_H * 8; j++) {
if ((sizej + j) < ImgWidth) {
y = Y[i * 8 * SampRate_Y_H + j];
u = U[(i / V_YtoU) * 8 * SampRate_Y_H + j / H_YtoU];
v = V[(i / V_YtoV) * 8 * SampRate_Y_H + j / H_YtoV];
rr = ((y << 8) + 18 * u + 367 * v) >> 8;
gg = ((y << 8) - 159 * u - 220 * v) >> 8;
bb = ((y << 8) + 411 * u - 29 * v) >> 8;
R = (unsigned char)rr;
G = (unsigned char)gg;
B = (unsigned char)bb;
if (rr & 0xffffff00) if (rr > 255) R = 255; else if (rr < 0) R = 0;
if (gg & 0xffffff00) if (gg > 255) G = 255; else if (gg < 0) G = 0;
if (bb & 0xffffff00) if (bb > 255) B = 255; else if (bb < 0) B = 0;
*lpbmp++ = B;
*lpbmp++ = G;
*lpbmp++ = R;
}
else break;
}
}
else break;
}
}
void CBitmap::Fast_IDCT(int * block)
{
short i;
for (i = 0; i < 8; i++)
idctrow(block + 8 * i);
for (i = 0; i < 8; i++)
idctcol(block + i);
}
string CBitmap::getModulePath()
{
char szDir[2048] = { 0 };
::GetModuleFileNameA(NULL, szDir, sizeof(szDir));
string strResult = szDir;
strResult = strResult.substr(0, strResult.find_last_of("\\"));
return strResult;
}
bool CBitmap::BmpZoom(BITMAPFILEHEADER head, BITMAPINFOHEADER info, unsigned char** pszSrc, unsigned int nSrcLength, unsigned char** pszDst, unsigned int& nDstLength)
{
printf("BmpZoom~~调用开始!\n");
bool bReturn = false;
try
{
FILE* file = fopen(string(getModulePath() + OLD_BMP_PATH).c_str(), "wb");
if (file == NULL)
throw - 1;
fwrite(*pszSrc, 1, nSrcLength, file);
fclose(file);
FILE *fpr1 = fopen(string(getModulePath() + OLD_BMP_PATH).c_str(), "rb");
FILE *fpw2 = fopen(string(getModulePath() + NEW_BMP_PATH).c_str(), "wb");
if (fpr1 == NULL || fpw2 == NULL)
throw - 2;
//读取原照片的头信息
fread(&head, sizeof(BITMAPFILEHEADER), 1, fpr1);
fread(&info, sizeof(BITMAPINFOHEADER), 1, fpr1);
unsigned int old_width = info.biWidth;//获取原图片的宽
unsigned int old_height = info.biHeight;//获取原图片的高
//获取原图片的位图数据
printf("BmpZoom~~old_width：%d \n", old_width);
printf("BmpZoom~~old_height：%d \n", old_height);
LONG srcDataLen = old_width*old_height * 3;
printf("BmpZoom~~srcDataLen：%d \n", srcDataLen);
if (srcDataLen <= 0)
throw - 3;
unsigned char *src_data = new unsigned char[srcDataLen];
if (src_data == NULL)
throw - 4;
printf("BmpZoom~~fseek!\n");
{ // 测试文件的大小
int errer = _fseeki64(fpr1, 0, SEEK_END);
if (errer != 0)
{ // 不等0，移动文件光标失败
printf("Failed to move cursor!(SEEK_END)\n");
return false;
}
// 获得当前文件指针位置，也就是间接获得文件大小
int fileSize = _ftelli64(fpr1);
printf("fpr1文件的大小：%d\n ", fileSize);
if (fileSize <= 54)
throw - 5;
errer = _fseeki64(fpr1, 0, SEEK_SET);
if (errer != 0)
{ // 不等0，移动文件光标失败
printf("Failed to move cursor!(SEEK_END)\n");
return false;
}
fileSize = _ftelli64(fpr1);
}
fseek(fpr1, 54, SEEK_SET);//向后偏移，就算超出文件，也只是指在文件尾部，不会返回-1
fread(src_data, old_width*old_height * 3, 1, fpr1);
fclose(fpr1);
printf("原图片的宽:%d\n", old_width);
printf("原图片的高:%d\n", old_height);
//修改原照片的宽高
unsigned int new_Width, new_Height;
old_width > 480 ? new_Width = 480 : new_Width = old_width;
old_height > 300 ? new_Height = 300 : new_Height = old_height;
unsigned int newSize = new_Width * new_Height * 3;
head.bfSize = newSize + 54;
info.biWidth = new_Width;
info.biHeight = new_Height;
//将修改过的头信息写进新照片
fwrite(&head, sizeof(BITMAPFILEHEADER), 1, fpw2);
fwrite(&info, sizeof(BITMAPINFOHEADER), 1, fpw2);
unsigned int i = 0, j = 0;
unsigned long dwsrcX, dwsrcY;
unsigned char *pucDest;
unsigned char *pucSrc;
unsigned char *dest_data = new unsigned char[newSize];
for (i = 0; i < new_Height; i++)
{
dwsrcY = i * old_height / new_Height;
pucDest = dest_data + i * new_Width * 3;
pucSrc = src_data + dwsrcY * old_width * 3;
for (j = 0; j < new_Width; j++)
{
dwsrcX = j * old_width / new_Width;
memcpy(pucDest + j * 3, pucSrc + dwsrcX * 3, 3);//数据拷贝
}
}
fseek(fpw2, 54, SEEK_SET);
fwrite(dest_data, newSize, 1, fpw2);
printf("生成 压缩bmp图片 成功!\n");
fclose(fpw2);
nDstLength = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + newSize;
*pszDst = new unsigned char[nDstLength];
unsigned char* tmpData = *pszDst;
memcpy_s(tmpData, sizeof(BITMAPFILEHEADER), &head, sizeof(BITMAPFILEHEADER));
tmpData += sizeof(BITMAPFILEHEADER);
memcpy_s(tmpData, sizeof(BITMAPINFOHEADER), &info, sizeof(BITMAPINFOHEADER));
tmpData += sizeof(BITMAPINFOHEADER);
memcpy_s(tmpData, newSize, dest_data, newSize);
//释放堆空间
delete[] dest_data;
dest_data = NULL;
delete[] src_data;
src_data = NULL;
return true;
}
catch (int& iErrorCode)
{
switch (iErrorCode)
{
case -1:
printf("生成old bmp文件 失败!\n");
break;
case -2:
printf("打开old bmp文件 失败 or 生成new bmp文件 失败!\n");
break;
case -3:
printf("BmpZoom~~srcDataLen <=0 返回!\n");
break;
case -4:
printf("BmpZoom~~src_data 申请内存失败!\n");
break;
case -5:
printf("fpr1文件的大小，小于54，返回\n");
break;
}
}
return bReturn;
}
bool CBitmap::Jpeg2Bmp(const char* pszSrc, int nSrcLength, unsigned char** pszDst, unsigned int& nDstLength)
{
FILE* hfjpg;//打开原本jpg格式的文件
DWORD ImgSize;
DWORD BufSize, JpegBufSize;
FILE* hfbmp;//生成目标bmp文件
unsigned char * hJpegBuf = NULL;//存储原本jpg格式的文件数据
unsigned char * hImgData = NULL;//存储新的数据的变量
int funcret;
LPBITMAPINFOHEADER lpImgData;
BITMAPFILEHEADER bf;//描述位图文件头的结构体
BITMAPINFOHEADER bi;//描述位图文件头信息的结构体
printf("传进来的图片路径：%s\n", pszSrc);
errno_t err = fopen_s(&hfjpg, pszSrc, "rb");//正确返回0，不正确返回非0
if (err != 0)
{
printf("文件打开失败\n");
}
//get jpg file length
fseek(hfjpg, 0L, SEEK_END);
JpegBufSize = ftell(hfjpg);
printf("原本图片数据（JpegBufSize）大小:%d\n", JpegBufSize);
//rewind to the beginning of the file
fseek(hfjpg, 0L, SEEK_SET);
hJpegBuf = new unsigned char[JpegBufSize];
if (hJpegBuf == NULL)
{
printf("存储原本jpg格式的文件数据（hJpegBuf） 分配内存失败，返回\n");
return false;
}
lpJpegBuf = hJpegBuf;//多一个变量指向这块内存
fread(hJpegBuf, sizeof(char), JpegBufSize, hfjpg);
fclose(hfjpg);
InitTable();
if ((funcret = InitTag()) != FUNC_OK)
{
delete[] hJpegBuf;
hJpegBuf = NULL;
return false;
}
//create new bitmapfileheader and bitmapinfoheader
memset((char *)&bf, 0, sizeof(BITMAPFILEHEADER));
memset((char *)&bi, 0, sizeof(BITMAPINFOHEADER));
bi.biSize = (DWORD)sizeof(BITMAPINFOHEADER);
bi.biWidth = (LONG)(ImgWidth);
bi.biHeight = (LONG)(ImgHeight);
bi.biPlanes = 1;
bi.biBitCount = 24;
bi.biClrUsed = 0;
bi.biClrImportant = 0;
bi.biCompression = BI_RGB;
NumColors = 0;
LineBytes = (DWORD)WIDTHBYTES(bi.biWidth*bi.biBitCount);
ImgSize = (DWORD)LineBytes*bi.biHeight;
bf.bfType = 0x4d42;
printf("描述位图文件头的结构体（BITMAPFILEHEADER）：%d\n", sizeof(BITMAPFILEHEADER));//如果没有#pragma pack(1)，sizeof(BITMAPFILEHEADER)是16
printf("描述位图文件头信息的结构体（BITMAPINFOHEADER）：%d\n", sizeof(BITMAPINFOHEADER));
printf("NumColors * sizeof(RGBQUAD)：%d\n", NumColors * sizeof(RGBQUAD));
bf.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + NumColors * sizeof(RGBQUAD) + ImgSize;
bf.bfOffBits = 54;//位图数据的偏移量，即位图文件头和位图信息头之后的字节数
BufSize = bf.bfSize - sizeof(BITMAPFILEHEADER); //描述位图文件头的结构体，文件头的结构体的大小是固定的，所以先减去，后面直接复制文件头的结构体即可
printf("文件大小(bf.bfSize)：%d\n", bf.bfSize);
printf("文件大小 - 位图文件头的结构体 = BufSize：%d\n", BufSize);
if (BufSize <= 0)
{
delete[] hJpegBuf;
hJpegBuf = NULL;
return FALSE;
}
hImgData = new unsigned char[BufSize];
if (hImgData == NULL)
{
printf("hImgData 申请内存失败！\n");
delete[] hJpegBuf;
hJpegBuf = NULL;
return FALSE;
}
printf("存储新的数据的变量（hImgData） 申请内存成功！\n");
lpImgData = (LPBITMAPINFOHEADER)hImgData;
printf("sizeof(BITMAPINFOHEADER)：%d\n", sizeof(BITMAPINFOHEADER));
printf("sizeof(bi)：%d\n", sizeof(bi));
memcpy(lpImgData, (char *)&bi, sizeof(BITMAPINFOHEADER));//描述位图文件头信息的结构体
if (lpImgData==NULL)
{
printf("lpImgData = NULL 返回 \n");
return false;
}
printf("sizeof(lpImgData)：%d\n", sizeof(lpImgData));
lpPtr = (char *)lpImgData + sizeof(BITMAPINFOHEADER);//mencpy完，指针往后移，并赋给新的全局指针（其他函数做一些格式转换处理）
if ((SampRate_Y_H == 0) || (SampRate_Y_V == 0))
{
delete[] hJpegBuf;
hJpegBuf = NULL;
delete[] hImgData;
hImgData = NULL;
printf("(SampRate_Y_H == 0) || (SampRate_Y_V == 0) 失败，返回\n");
return false;
}
printf("Decode接口，调用开始\n");
funcret = Decode();//格式转换的主要函数
printf("Decode接口，调用结束\n");
bool retOK = false;
if (funcret == FUNC_OK)
{
//生成bmp图片（可以不生成这个文件的，只是为了看）
fopen_s(&hfbmp, string(getModulePath() + "\\jpeg2bmp.bmp").c_str(), "wb");
fwrite((LPSTR)&bf, sizeof(BITMAPFILEHEADER), 1, hfbmp);
fwrite((LPSTR)lpImgData, sizeof(char), BufSize, hfbmp);
fclose(hfbmp);
printf(" 生成目标 bmp 图片成功 \n");
{
//bmp图片转为二进制
unsigned int nSrcLength = BufSize + sizeof(BITMAPFILEHEADER);//生成目标bmp文件的大小
printf("生成目标bmp文件的大小(nSrcLength)：%d\n", nSrcLength);
unsigned char *pszSrcZoom = new unsigned char[nSrcLength]; //申请内存，主要是想把bmp文件的数据读出来
if (pszSrcZoom == NULL)
{
printf("pszSrcZoom 申请内存失败！\n");
delete[] hJpegBuf;
hJpegBuf = NULL;
delete[] hImgData;
hImgData = NULL;
return false;
}
unsigned char* tmpData = pszSrcZoom;
memcpy_s(tmpData, sizeof(BITMAPFILEHEADER), &bf, sizeof(BITMAPFILEHEADER));//位图的文件头结构体
tmpData += sizeof(BITMAPFILEHEADER);//指针往后移
memcpy_s(tmpData, BufSize, lpImgData, BufSize);//复制bmp的数据
printf("测试 ~~~~aaaaaaaaaaaaa\n");
unsigned char* pszDstZoom = NULL;//存bmp图片压缩后的数据
bool retBmpZoom = BmpZoom(bf, *lpImgData, &pszSrcZoom, nSrcLength, &pszDstZoom, nDstLength);
if (pszSrcZoom != NULL)
{
delete[] pszSrcZoom;
pszSrcZoom = NULL;
}
if (retBmpZoom && pszDstZoom != NULL)
{
*pszDst = new unsigned char[nDstLength];
if (*pszDst == NULL)
{
printf("*pszDst 申请内存失败！\n");
delete[] hJpegBuf;
hJpegBuf = NULL;
delete[] hImgData;
hImgData = NULL;
return false;
}
memcpy_s(*pszDst, nDstLength, pszDstZoom, nDstLength);
delete[] pszDstZoom;
pszDstZoom = NULL;
retOK = true;
}
}
}
delete[] hJpegBuf;
hJpegBuf = NULL;
delete[] hImgData;
hImgData = NULL;
retOK ? printf("retBmpZoom压缩成功!\n") : printf("retBmpZoom压缩失败!\n");
return retOK;
}
int CBitmap::InitTag()
{
BOOL finish = FALSE;
BYTE id;
short llength;
short i, j, k;
short huftab1, huftab2;
short huftabindex;
BYTE hf_table_index;
BYTE qt_table_index;
BYTE comnum;
unsigned char *lptemp;
short ccount;
lp = lpJpegBuf + 2;
while (!finish) {
id = *(lp + 1);
lp += 2;
switch (id) {
case M_APP0:
llength = MAKEWORD(*(lp + 1), *lp);
lp += llength;
break;
case M_DQT:
llength = MAKEWORD(*(lp + 1), *lp);
qt_table_index = (*(lp + 2)) & 0x0f;
lptemp = lp + 3;
if (llength < 80) {
for (i = 0; i < 64; i++)
qt_table[qt_table_index][i] = (short)*(lptemp++);
}
else {
for (i = 0; i < 64; i++)
qt_table[qt_table_index][i] = (short)*(lptemp++);
qt_table_index = (*(lptemp++)) & 0x0f;
for (i = 0; i < 64; i++)
qt_table[qt_table_index][i] = (short)*(lptemp++);
}
lp += llength;
break;
case M_SOF0:
llength = MAKEWORD(*(lp + 1), *lp);
ImgHeight = MAKEWORD(*(lp + 4), *(lp + 3));
ImgWidth = MAKEWORD(*(lp + 6), *(lp + 5));
comp_num = *(lp + 7);
if ((comp_num != 1) && (comp_num != 3))
return FUNC_FORMAT_ERROR;
if (comp_num == 3) {
comp_index[0] = *(lp + 8);
SampRate_Y_H = (*(lp + 9)) >> 4;
SampRate_Y_V = (*(lp + 9)) & 0x0f;
YQtTable = (short *)qt_table[*(lp + 10)];
comp_index[1] = *(lp + 11);
SampRate_U_H = (*(lp + 12)) >> 4;
SampRate_U_V = (*(lp + 12)) & 0x0f;
UQtTable = (short *)qt_table[*(lp + 13)];
comp_index[2] = *(lp + 14);
SampRate_V_H = (*(lp + 15)) >> 4;
SampRate_V_V = (*(lp + 15)) & 0x0f;
VQtTable = (short *)qt_table[*(lp + 16)];
}
else {
comp_index[0] = *(lp + 8);
SampRate_Y_H = (*(lp + 9)) >> 4;
SampRate_Y_V = (*(lp + 9)) & 0x0f;
YQtTable = (short *)qt_table[*(lp + 10)];
comp_index[1] = *(lp + 8);
SampRate_U_H = 1;
SampRate_U_V = 1;
UQtTable = (short *)qt_table[*(lp + 10)];
comp_index[2] = *(lp + 8);
SampRate_V_H = 1;
SampRate_V_V = 1;
VQtTable = (short *)qt_table[*(lp + 10)];
}
lp += llength;
break;
case M_DHT:
llength = MAKEWORD(*(lp + 1), *lp);
if (llength < 0xd0) {
huftab1 = (short)(*(lp + 2)) >> 4; //huftab1=0,1
huftab2 = (short)(*(lp + 2)) & 0x0f; //huftab2=0,1
huftabindex = huftab1 * 2 + huftab2;
lptemp = lp + 3;
for (i = 0; i < 16; i++)
code_len_table[huftabindex][i] = (short)(*(lptemp++));
j = 0;
for (i = 0; i < 16; i++)
if (code_len_table[huftabindex][i] != 0) {
k = 0;
while (k < code_len_table[huftabindex][i]) {
code_value_table[huftabindex][k + j] = (short)(*(lptemp++));
k++;
}
j += k;
}
i = 0;
while (code_len_table[huftabindex][i] == 0)
i++;
for (j = 0; j < i; j++) {
huf_min_value[huftabindex][j] = 0;
huf_max_value[huftabindex][j] = 0;
}
huf_min_value[huftabindex][i] = 0;
huf_max_value[huftabindex][i] = code_len_table[huftabindex][i] - 1;
for (j = i + 1; j < 16; j++) {
huf_min_value[huftabindex][j] = (huf_max_value[huftabindex][j - 1] + 1) << 1;
huf_max_value[huftabindex][j] = huf_min_value[huftabindex][j] + code_len_table[huftabindex][j] - 1;
}
code_pos_table[huftabindex][0] = 0;
for (j = 1; j < 16; j++)
code_pos_table[huftabindex][j] = code_len_table[huftabindex][j - 1] + code_pos_table[huftabindex][j - 1];
lp += llength;
} //if
else {
hf_table_index = *(lp + 2);
lp += 2;
while (hf_table_index != 0xff) {
huftab1 = (short)hf_table_index >> 4; //huftab1=0,1
huftab2 = (short)hf_table_index & 0x0f; //huftab2=0,1
huftabindex = huftab1 * 2 + huftab2;
lptemp = lp + 1;
ccount = 0;
for (i = 0; i < 16; i++) {
code_len_table[huftabindex][i] = (short)(*(lptemp++));
ccount += code_len_table[huftabindex][i];
}
ccount += 17;
j = 0;
for (i = 0; i < 16; i++)
if (code_len_table[huftabindex][i] != 0) {
k = 0;
while (k < code_len_table[huftabindex][i])
{
code_value_table[huftabindex][k + j] = (short)(*(lptemp++));
k++;
}
j += k;
}
i = 0;
while (code_len_table[huftabindex][i] == 0)
i++;
for (j = 0; j < i; j++) {
huf_min_value[huftabindex][j] = 0;
huf_max_value[huftabindex][j] = 0;
}
huf_min_value[huftabindex][i] = 0;
huf_max_value[huftabindex][i] = code_len_table[huftabindex][i] - 1;
for (j = i + 1; j < 16; j++) {
huf_min_value[huftabindex][j] = (huf_max_value[huftabindex][j - 1] + 1) << 1;
huf_max_value[huftabindex][j] = huf_min_value[huftabindex][j] + code_len_table[huftabindex][j] - 1;
}
code_pos_table[huftabindex][0] = 0;
for (j = 1; j < 16; j++)
code_pos_table[huftabindex][j] = code_len_table[huftabindex][j - 1] + code_pos_table[huftabindex][j - 1];
lp += ccount;
hf_table_index = *lp;
} //while
} //else
break;
case M_DRI:
llength = MAKEWORD(*(lp + 1), *lp);
restart = MAKEWORD(*(lp + 3), *(lp + 2));
lp += llength;
break;
case M_SOS:
llength = MAKEWORD(*(lp + 1), *lp);
comnum = *(lp + 2);
if (comnum != comp_num)
return FUNC_FORMAT_ERROR;
lptemp = lp + 3;
for (i = 0; i < comp_num; i++) {
if (*lptemp == comp_index[0]) {
YDcIndex = (*(lptemp + 1)) >> 4; //Y
YAcIndex = ((*(lptemp + 1)) & 0x0f) + 2;
}
else {
UVDcIndex = (*(lptemp + 1)) >> 4; //U,V
UVAcIndex = ((*(lptemp + 1)) & 0x0f) + 2;
}
lptemp += 2;
}
lp += llength;
finish = TRUE;
break;
case M_EOI:
return FUNC_FORMAT_ERROR;
break;
default:
if ((id & 0xf0) != 0xd0) {
llength = MAKEWORD(*(lp + 1), *lp);
lp += llength;
}
else lp += 2;
break;
} //switch
} //while
return FUNC_OK;
}
void CBitmap::InitTable()
{
short i, j;
sizei = sizej = 0;
ImgWidth = ImgHeight = 0;
rrun = vvalue = 0;
BitPos = 0;
CurByte = 0;
IntervalFlag = FALSE;
restart = 0;
for (i = 0; i < 3; i++)
for (j = 0; j < 64; j++)
qt_table[i][j] = 0;
comp_num = 0;
HufTabIndex = 0;
for (i = 0; i < 3; i++)
comp_index[i] = 0;
for (i = 0; i < 4; i++)
for (j = 0; j < 16; j++) {
code_len_table[i][j] = 0;
code_pos_table[i][j] = 0;
huf_max_value[i][j] = 0;
huf_min_value[i][j] = 0;
}
for (i = 0; i < 4; i++)
for (j = 0; j < 256; j++)
code_value_table[i][j] = 0;
for (i = 0; i < 10 * 64; i++) {
MCUBuffer[i] = 0;
QtZzMCUBuffer[i] = 0;
}
for (i = 0; i < 64; i++) {
Y[i] = 0;
U[i] = 0;
V[i] = 0;
BlockBuffer[i] = 0;
}
ycoef = ucoef = vcoef = 0;
}
int CBitmap::Decode()
{
int funcret;
Y_in_MCU = SampRate_Y_H * SampRate_Y_V;
U_in_MCU = SampRate_U_H * SampRate_U_V;
V_in_MCU = SampRate_V_H * SampRate_V_V;
H_YtoU = SampRate_Y_H / SampRate_U_H;
V_YtoU = SampRate_Y_V / SampRate_U_V;
H_YtoV = SampRate_Y_H / SampRate_V_H;
V_YtoV = SampRate_Y_V / SampRate_V_V;
Initialize_Fast_IDCT();
while ((funcret = DecodeMCUBlock()) == FUNC_OK) {
interval++;
if ((restart) && (interval % restart == 0))
IntervalFlag = TRUE;
else
IntervalFlag = FALSE;
IQtIZzMCUComponent(0);
IQtIZzMCUComponent(1);
IQtIZzMCUComponent(2);
GetYUV(0);
GetYUV(1);
GetYUV(2);
StoreBuffer();
sizej += SampRate_Y_H * 8;
if (sizej >= ImgWidth) {
sizej = 0;
sizei += SampRate_Y_V * 8;
}
if ((sizej == 0) && (sizei >= ImgHeight))
break;
}
return funcret;
}
int CBitmap::DecodeMCUBlock()
{
short *lpMCUBuffer;
short i, j;
int funcret;
if (IntervalFlag) {
lp += 2;
ycoef = ucoef = vcoef = 0;
BitPos = 0;
CurByte = 0;
}
switch (comp_num) {
case 3:
lpMCUBuffer = MCUBuffer;
for (i = 0; i < SampRate_Y_H*SampRate_Y_V; i++) //Y
{
funcret = HufBlock(YDcIndex, YAcIndex);
if (funcret != FUNC_OK)
return funcret;
BlockBuffer[0] = BlockBuffer[0] + ycoef;
ycoef = BlockBuffer[0];
for (j = 0; j < 64; j++)
*lpMCUBuffer++ = BlockBuffer[j];
}
for (i = 0; i < SampRate_U_H*SampRate_U_V; i++) //U
{
funcret = HufBlock(UVDcIndex, UVAcIndex);
if (funcret != FUNC_OK)
return funcret;
BlockBuffer[0] = BlockBuffer[0] + ucoef;
ucoef = BlockBuffer[0];
for (j = 0; j < 64; j++)
*lpMCUBuffer++ = BlockBuffer[j];
}
for (i = 0; i < SampRate_V_H*SampRate_V_V; i++) //V
{
funcret = HufBlock(UVDcIndex, UVAcIndex);
if (funcret != FUNC_OK)
return funcret;
BlockBuffer[0] = BlockBuffer[0] + vcoef;
vcoef = BlockBuffer[0];
for (j = 0; j < 64; j++)
*lpMCUBuffer++ = BlockBuffer[j];
}
break;
case 1:
lpMCUBuffer = MCUBuffer;
funcret = HufBlock(YDcIndex, YAcIndex);
if (funcret != FUNC_OK)
return funcret;
BlockBuffer[0] = BlockBuffer[0] + ycoef;
ycoef = BlockBuffer[0];
for (j = 0; j < 64; j++)
*lpMCUBuffer++ = BlockBuffer[j];
for (i = 0; i < 128; i++)
*lpMCUBuffer++ = 0;
break;
default:
return FUNC_FORMAT_ERROR;
}
return FUNC_OK;
}
int CBitmap::HufBlock(BYTE dchufindex, BYTE achufindex)
{
short count = 0;
short i;
int funcret;
//dc
HufTabIndex = dchufindex;
funcret = DecodeElement();
if (funcret != FUNC_OK)
return funcret;
BlockBuffer[count++] = vvalue;
//ac
HufTabIndex = achufindex;
while (count < 64) {
funcret = DecodeElement();
if (funcret != FUNC_OK)
return funcret;
if ((rrun == 0) && (vvalue == 0)) {
for (i = count; i < 64; i++)
BlockBuffer[i] = 0;
count = 64;
}
else {
for (i = 0; i < rrun; i++)
BlockBuffer[count++] = 0;
BlockBuffer[count++] = vvalue;
}
}
return FUNC_OK;
}
int CBitmap::DecodeElement()
{
int thiscode, tempcode;
unsigned short temp, valueex;
short codelen;
BYTE hufexbyte, runsize, tempsize, sign;
BYTE newbyte, lastbyte;
if (BitPos >= 1) {
BitPos--;
thiscode = (BYTE)CurByte >> BitPos;
CurByte = CurByte & And[BitPos];
}
else {
lastbyte = ReadByte();
BitPos--;
newbyte = CurByte & And[BitPos];
thiscode = lastbyte >> 7;
CurByte = newbyte;
}
codelen = 1;
while ((thiscode < huf_min_value[HufTabIndex][codelen - 1]) ||
(code_len_table[HufTabIndex][codelen - 1] == 0) ||
(thiscode > huf_max_value[HufTabIndex][codelen - 1]))
{
if (BitPos >= 1) {
BitPos--;
tempcode = (BYTE)CurByte >> BitPos;
CurByte = CurByte & And[BitPos];
}
else {
lastbyte = ReadByte();
BitPos--;
newbyte = CurByte & And[BitPos];
tempcode = (BYTE)lastbyte >> 7;
CurByte = newbyte;
}
thiscode = (thiscode << 1) + tempcode;
codelen++;
if (codelen > 16)
return FUNC_FORMAT_ERROR;
} //while
temp = thiscode - huf_min_value[HufTabIndex][codelen - 1] + code_pos_table[HufTabIndex][codelen - 1];
hufexbyte = (BYTE)code_value_table[HufTabIndex][temp];
rrun = (short)(hufexbyte >> 4);
runsize = hufexbyte & 0x0f;
if (runsize == 0) {
vvalue = 0;
return FUNC_OK;
}
tempsize = runsize;
if (BitPos >= runsize) {
BitPos -= runsize;
valueex = (BYTE)CurByte >> BitPos;
CurByte = CurByte & And[BitPos];
}
else {
valueex = CurByte;
tempsize -= BitPos;
while (tempsize > 8) {
lastbyte = ReadByte();
valueex = (valueex << 8) + (BYTE)lastbyte;
tempsize -= 8;
} //while
lastbyte = ReadByte();
BitPos -= tempsize;
valueex = (valueex << tempsize) + (lastbyte >> BitPos);
CurByte = lastbyte & And[BitPos];
} //else
sign = valueex >> (runsize - 1);
if (sign)
vvalue = valueex;
else {
valueex = valueex ^ 0xffff;
temp = 0xffff << runsize;
vvalue = -(short)(valueex^temp);
}
return FUNC_OK;
}
void CBitmap::IQtIZzMCUComponent(short flag)
{
short H, VV;
short i, j;
int *pQtZzMCUBuffer;
short *pMCUBuffer;
pMCUBuffer = MCUBuffer;
pQtZzMCUBuffer = QtZzMCUBuffer;
switch (flag) {
case 0:
H = SampRate_Y_H;
VV = SampRate_Y_V;
pMCUBuffer = MCUBuffer;
pQtZzMCUBuffer = QtZzMCUBuffer;
break;
case 1:
H = SampRate_U_H;
VV = SampRate_U_V;
pMCUBuffer = MCUBuffer + Y_in_MCU * 64;
pQtZzMCUBuffer = QtZzMCUBuffer + Y_in_MCU * 64;
break;
case 2:
H = SampRate_V_H;
VV = SampRate_V_V;
pMCUBuffer = MCUBuffer + (Y_in_MCU + U_in_MCU) * 64;
pQtZzMCUBuffer = QtZzMCUBuffer + (Y_in_MCU + U_in_MCU) * 64;
break;
}
for (i = 0; i < VV; i++)
for (j = 0; j < H; j++)
IQtIZzBlock(pMCUBuffer + (i*H + j) * 64, pQtZzMCUBuffer + (i*H + j) * 64, flag);
}
void CBitmap::IQtIZzBlock(short *s, int * d, short flag)
{
short i, j;
short tag;
short *pQt;
int buffer2[8][8];
int *buffer1;
short offset;
pQt = YQtTable;
switch (flag) {
case 0:
pQt = YQtTable;
offset = 128;
break;
case 1:
pQt = UQtTable;
offset = 0;
break;
case 2:
pQt = VQtTable;
offset = 0;
break;
}
for (i = 0; i < 8; i++)
for (j = 0; j < 8; j++) {
tag = Zig_Zag[i][j];
buffer2[i][j] = (int)s[tag] * (int)pQt[tag];
}
buffer1 = (int *)buffer2;
Fast_IDCT(buffer1);
for (i = 0; i < 8; i++)
for (j = 0; j < 8; j++)
d[i * 8 + j] = buffer2[i][j] + offset;
}
BYTE CBitmap::ReadByte()
{
BYTE i;
i = *(lp++);
if (i == 0xff)
lp++;
BitPos = 8;
CurByte = i;
return i;
}
void CBitmap::Initialize_Fast_IDCT()
{
short i;
iclp = iclip + 512;
for (i = -512; i < 512; i++)
iclp[i] = (i < -256) ? -256 : ((i > 255) ? 255 : i);
}
void CBitmap::idctrow(int * blk)
{
int x0, x1, x2, x3, x4, x5, x6, x7, x8;
//intcut
if (!((x1 = blk[4] << 11) | (x2 = blk[6]) | (x3 = blk[2]) |
(x4 = blk[1]) | (x5 = blk[7]) | (x6 = blk[5]) | (x7 = blk[3])))
{
blk[0] = blk[1] = blk[2] = blk[3] = blk[4] = blk[5] = blk[6] = blk[7] = blk[0] << 3;
return;
}
x0 = (blk[0] << 11) + 128; // for proper rounding in the fourth stage
//first stage
x8 = W7 * (x4 + x5);
x4 = x8 + (W1 - W7)*x4;
x5 = x8 - (W1 + W7)*x5;
x8 = W3 * (x6 + x7);
x6 = x8 - (W3 - W5)*x6;
x7 = x8 - (W3 + W5)*x7;
//second stage
x8 = x0 + x1;
x0 -= x1;
x1 = W6 * (x3 + x2);
x2 = x1 - (W2 + W6)*x2;
x3 = x1 + (W2 - W6)*x3;
x1 = x4 + x6;
x4 -= x6;
x6 = x5 + x7;
x5 -= x7;
//third stage
x7 = x8 + x3;
x8 -= x3;
x3 = x0 + x2;
x0 -= x2;
x2 = (181 * (x4 + x5) + 128) >> 8;
x4 = (181 * (x4 - x5) + 128) >> 8;
//fourth stage
blk[0] = (x7 + x1) >> 8;
blk[1] = (x3 + x2) >> 8;
blk[2] = (x0 + x4) >> 8;
blk[3] = (x8 + x6) >> 8;
blk[4] = (x8 - x6) >> 8;
blk[5] = (x0 - x4) >> 8;
blk[6] = (x3 - x2) >> 8;
blk[7] = (x7 - x1) >> 8;
}
void CBitmap::idctcol(int * blk)
{
int x0, x1, x2, x3, x4, x5, x6, x7, x8;
//intcut
if (!((x1 = (blk[8 * 4] << 8)) | (x2 = blk[8 * 6]) | (x3 = blk[8 * 2]) |
(x4 = blk[8 * 1]) | (x5 = blk[8 * 7]) | (x6 = blk[8 * 5]) | (x7 = blk[8 * 3])))
{
blk[8 * 0] = blk[8 * 1] = blk[8 * 2] = blk[8 * 3] = blk[8 * 4] = blk[8 * 5]
= blk[8 * 6] = blk[8 * 7] = iclp[(blk[8 * 0] + 32) >> 6];
return;
}
x0 = (blk[8 * 0] << 8) + 8192;
//first stage
x8 = W7 * (x4 + x5) + 4;
x4 = (x8 + (W1 - W7)*x4) >> 3;
x5 = (x8 - (W1 + W7)*x5) >> 3;
x8 = W3 * (x6 + x7) + 4;
x6 = (x8 - (W3 - W5)*x6) >> 3;
x7 = (x8 - (W3 + W5)*x7) >> 3;
//second stage
x8 = x0 + x1;
x0 -= x1;
x1 = W6 * (x3 + x2) + 4;
x2 = (x1 - (W2 + W6)*x2) >> 3;
x3 = (x1 + (W2 - W6)*x3) >> 3;
x1 = x4 + x6;
x4 -= x6;
x6 = x5 + x7;
x5 -= x7;
//third stage
x7 = x8 + x3;
x8 -= x3;
x3 = x0 + x2;
x0 -= x2;
x2 = (181 * (x4 + x5) + 128) >> 8;
x4 = (181 * (x4 - x5) + 128) >> 8;
//fourth stage
blk[8 * 0] = iclp[(x7 + x1) >> 14];
blk[8 * 1] = iclp[(x3 + x2) >> 14];
blk[8 * 2] = iclp[(x0 + x4) >> 14];
blk[8 * 3] = iclp[(x8 + x6) >> 14];
blk[8 * 4] = iclp[(x8 - x6) >> 14];
blk[8 * 5] = iclp[(x0 - x4) >> 14];
blk[8 * 6] = iclp[(x3 - x2) >> 14];
blk[8 * 7] = iclp[(x7 - x1) >> 14];
}到了这里，关于BMP图像处理（jpeg转bmp，以及bmp图片缩放，附代码）的文章就介绍完了。如果您还想了解更多内容，请在右上角搜索TOY模板网以前的文章或继续浏览下面的相关文章，希望大家以后多多支持TOY模板网！
