我是在linux下写的这程序.感觉和VC下的差不多,所以在这里问下达人.我是新手,所以实在不懂了.
#include<stdio.h>
#include<malloc.h>
#pragma pack(2);typedef struct
{
unsigned short bfType; /* 文件类型, 必须为 "BM"(0x4D42) */
unsigned long bfSize; /* 文件的大小(字节) */
unsigned short bfReserved1; /* 保留, 必须为 0 */
unsigned short bfReserved2; /* 保留, 必须为 0 */
unsigned long bfoffBits; /* 位图阵列相对于文件头的偏移量(字节) */
} BITMAPFILEHEADER; /* 文件头结构 */ typedef struct
{
unsigned long biSize; /* size of BITMAPINFOHEADER */
unsigned long biWidth; /* 位图宽度(像素) */
unsigned long biHeight; /* 位图高度(像素) */
unsigned short biPlanes; /* 目标设备的位平面数, 必须置为1 */
unsigned short biBitCount; /* 每个像素的位数, 1,4,8或24 */
unsigned long biCompress; /* 位图阵列的压缩方法,0=不压缩 */
unsigned long biSizeImage; /* 图像大小(字节) */
unsigned long biXPelsPerMeter; /* 目标设备水平每米像素个数 */
unsigned long biYPelsPerMeter; /* 目标设备垂直每米像素个数 */
unsigned long biClrUsed; /* 位图实际使用的颜色表的颜色数 */
unsigned long biClrImportant; /* 重要颜色索引的个数 */
} BITMAPINFOHEADER; /* 位图信息头结构 */
typedef struct
{
unsigned char rgbBlue;
unsigned char rgbGreen;
unsigned char rgbRed;
unsigned char rgbReserved;
} RGBQUAD;typedef struct
{
BITMAPINFOHEADER bmiHeader;
RGBQUAD bmiColors[256];
}BITMAPINFO, * PBITMAPINFO;BITMAPFILEHEADER bfile, bbfile;
BITMAPINFOHEADER binfo, bbinfo;BITMAPINFO bmi; //»Ò¶È͌ʱÓÃÕâžö.
PBITMAPINFO pbmi;
FILE *in, *out;int open()
{
if((in = fopen("girl.bmp", "rb")) == NULL)
{
printf("Open file failed.\n");
exit(-1);
}
if((out = fopen("gray_girl.bmp", "wb")) == NULL)
{
printf("Create copy file failed.\n");
exit(-1);
}
return 0;
}int init_bmpStruct()
{
fread(&bfile.bfType, sizeof(bfile.bfType), 1, in);
fwrite(&bfile.bfType, sizeof(bfile.bfType), 1, out);
fread(&bfile.bfSize, sizeof(bfile.bfSize), 1, in);
fwrite(&bfile.bfSize, sizeof(bfile.bfSize), 1, out);
fread(&bfile.bfReserved1, sizeof(bbfile.bfReserved1), 1, in);
fwrite(&bfile.bfReserved1, sizeof(bfile.bfReserved1), 1, out); fread(&bfile.bfReserved2, sizeof(bfile.bfReserved2), 1, in);
fwrite(&bfile.bfReserved2, sizeof(bfile.bfReserved2), 1, out); fread(&bfile.bfoffBits, sizeof(bfile.bfoffBits), 1, in);
fwrite(&bfile.bfoffBits, sizeof(bfile.bfoffBits), 1, out);
fread(&binfo.biSize, sizeof(binfo.biSize), 1, in);
fwrite(&binfo.biSize, sizeof(binfo.biSize), 1, out); fread(&binfo. biWidth, sizeof(binfo. biWidth), 1, in);
fwrite(&binfo.biWidth, sizeof(binfo.biWidth), 1, out); fread(&binfo.biHeight, sizeof(binfo.biHeight), 1, in);
fwrite(&binfo.biHeight, sizeof(binfo.biHeight), 1, out); fread(&binfo.biPlanes, sizeof(binfo.biPlanes), 1, in);
fwrite(&binfo.biPlanes, sizeof(binfo.biPlanes), 1, out); fread(&binfo.biBitCount, sizeof(binfo.biBitCount), 1, in);
fwrite(&binfo.biBitCount, sizeof(binfo.biBitCount), 1, out);
fread(&binfo.biCompress, sizeof(binfo.biCompress), 1, in);
fwrite(&binfo.biCompress, sizeof(binfo.biCompress), 1, out); fread(&binfo.biSizeImage, sizeof(binfo.biSizeImage), 1, in);
fwrite(&binfo.biSizeImage, sizeof(binfo.biSizeImage), 1, out); fread(&binfo.biXPelsPerMeter, sizeof(binfo.biXPelsPerMeter), 1, in);
fwrite(&binfo.biXPelsPerMeter, sizeof(binfo.biXPelsPerMeter), 1, out); fread(&binfo.biYPelsPerMeter, sizeof(binfo.biYPelsPerMeter), 1, in);
fwrite(&binfo.biYPelsPerMeter, sizeof(binfo.biYPelsPerMeter), 1, out); fread(&binfo.biClrUsed, sizeof(binfo.biClrUsed), 1, in);
fwrite(&binfo.biClrUsed, sizeof(binfo.biClrUsed), 1, out); fread(&binfo.biClrImportant, sizeof(binfo.biClrImportant), 1, in);
fwrite(&binfo.biClrImportant, sizeof(binfo.biClrImportant), 1, out);
printf("biSize = %ld\n",binfo.biSize);
printf("biWidth = %ld\n",binfo.biWidth);
printf("biHeight = %ld\n",binfo.biHeight);
printf("biPlanes = %d\n",binfo.biPlanes);
printf("biBitCount = %d\n",binfo.biBitCount);
printf("biCompress = %d\n",binfo.biCompress);
printf("biSizeImage = %ld\n",binfo.biSizeImage);
printf("biXpersPerMeter = %ld\n",binfo.biXPelsPerMeter);
printf("biYPersPerMeter = %ld\n",binfo.biYPelsPerMeter);
printf("biClrUsed = %ld\n",binfo.biClrUsed);
printf("biClrImportant = %ld\n", binfo.biClrImportant);
return 0;}
int WritePixtoFile()
{
int i = 0, j = 0;
unsigned long bboffest = bbfile.bfoffBits;
unsigned long boffest = bfile.bfoffBits;
int nBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32);
int bnBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32);
int Y;
unsigned char YY;
int R, G, B;
int RR, GG, BB;
long count = 0;
unsigned char *RGBbuffer = (unsigned char*)malloc(nBufferWide * binfo.biHeight);
unsigned char *bRGBbuffer = (unsigned char*)malloc(bnBufferWide * binfo.biHeight);
fseek(in, bboffest, SEEK_SET); ???这句定位是不是有问题?因为最后保存的图像一片黑.
fread(RGBbuffer, sizeof(unsigned char), nBufferWide * binfo.biHeight, in); for(i = binfo.biWidth -1 ; i >= 0; i--)
{
for(j = binfo.biHeight - 1; j >=0 ; j--)
{ R = (int)(*(RGBbuffer + i*3 + j));
G = (int)(*(RGBbuffer + i*3 + j + 1));
B = (int)(*(RGBbuffer+ i*3 + j + 2)); Y = ((66 * R + 129 * G + 25 * B + 128)>>8) + 16;
YY = (unsigned char) ((Y<0)?0:((Y>255)?255:Y));
RR = YY;
GG = YY;
BB = YY;
printf("YY = %d,", YY);
*(bRGBbuffer + i* 3 +j) = RR;
*(bRGBbuffer + i* 3 +j +1) = RR;
*(bRGBbuffer + i* 3 +j +2) = RR;
//memcpy(bRGBbuffer++, &YY, sizeof(unsigned char));
//printf("YY = %u, count = %ld\n", YY, count);
}
}
fwrite(bRGBbuffer ,1 , bnBufferWide * binfo.biHeight,out);
}int main()
{
open();
init_bmpStruct(); WritePixtoFile();
fclose(in);
fclose(out);
printf("BITMAPFILEHEADER size = %d,BITMAPINFOHEADER size = %d, RGBQUAD size = %d\n ", sizeof(BITMAPFILEHEADER), sizeof(BITMAPINFOHEADER), sizeof(RGBQUAD));
return 1;
}girl.bmp是一个24位的BMP图像,320*240的.
但是保存的gray_girl.bmp,就是一片黑啊~是不是offset定位错了?但是不知道怎么错的.
哪位朋友知道啊.我是新手.点指一下.非常感激!
#include<stdio.h>
#include<malloc.h>
#pragma pack(2);typedef struct
{
unsigned short bfType; /* 文件类型, 必须为 "BM"(0x4D42) */
unsigned long bfSize; /* 文件的大小(字节) */
unsigned short bfReserved1; /* 保留, 必须为 0 */
unsigned short bfReserved2; /* 保留, 必须为 0 */
unsigned long bfoffBits; /* 位图阵列相对于文件头的偏移量(字节) */
} BITMAPFILEHEADER; /* 文件头结构 */ typedef struct
{
unsigned long biSize; /* size of BITMAPINFOHEADER */
unsigned long biWidth; /* 位图宽度(像素) */
unsigned long biHeight; /* 位图高度(像素) */
unsigned short biPlanes; /* 目标设备的位平面数, 必须置为1 */
unsigned short biBitCount; /* 每个像素的位数, 1,4,8或24 */
unsigned long biCompress; /* 位图阵列的压缩方法,0=不压缩 */
unsigned long biSizeImage; /* 图像大小(字节) */
unsigned long biXPelsPerMeter; /* 目标设备水平每米像素个数 */
unsigned long biYPelsPerMeter; /* 目标设备垂直每米像素个数 */
unsigned long biClrUsed; /* 位图实际使用的颜色表的颜色数 */
unsigned long biClrImportant; /* 重要颜色索引的个数 */
} BITMAPINFOHEADER; /* 位图信息头结构 */
typedef struct
{
unsigned char rgbBlue;
unsigned char rgbGreen;
unsigned char rgbRed;
unsigned char rgbReserved;
} RGBQUAD;typedef struct
{
BITMAPINFOHEADER bmiHeader;
RGBQUAD bmiColors[256];
}BITMAPINFO, * PBITMAPINFO;BITMAPFILEHEADER bfile, bbfile;
BITMAPINFOHEADER binfo, bbinfo;BITMAPINFO bmi; //»Ò¶È͌ʱÓÃÕâžö.
PBITMAPINFO pbmi;
FILE *in, *out;int open()
{
if((in = fopen("girl.bmp", "rb")) == NULL)
{
printf("Open file failed.\n");
exit(-1);
}
if((out = fopen("gray_girl.bmp", "wb")) == NULL)
{
printf("Create copy file failed.\n");
exit(-1);
}
return 0;
}int init_bmpStruct()
{
fread(&bfile.bfType, sizeof(bfile.bfType), 1, in);
fwrite(&bfile.bfType, sizeof(bfile.bfType), 1, out);
fread(&bfile.bfSize, sizeof(bfile.bfSize), 1, in);
fwrite(&bfile.bfSize, sizeof(bfile.bfSize), 1, out);
fread(&bfile.bfReserved1, sizeof(bbfile.bfReserved1), 1, in);
fwrite(&bfile.bfReserved1, sizeof(bfile.bfReserved1), 1, out); fread(&bfile.bfReserved2, sizeof(bfile.bfReserved2), 1, in);
fwrite(&bfile.bfReserved2, sizeof(bfile.bfReserved2), 1, out); fread(&bfile.bfoffBits, sizeof(bfile.bfoffBits), 1, in);
fwrite(&bfile.bfoffBits, sizeof(bfile.bfoffBits), 1, out);
fread(&binfo.biSize, sizeof(binfo.biSize), 1, in);
fwrite(&binfo.biSize, sizeof(binfo.biSize), 1, out); fread(&binfo. biWidth, sizeof(binfo. biWidth), 1, in);
fwrite(&binfo.biWidth, sizeof(binfo.biWidth), 1, out); fread(&binfo.biHeight, sizeof(binfo.biHeight), 1, in);
fwrite(&binfo.biHeight, sizeof(binfo.biHeight), 1, out); fread(&binfo.biPlanes, sizeof(binfo.biPlanes), 1, in);
fwrite(&binfo.biPlanes, sizeof(binfo.biPlanes), 1, out); fread(&binfo.biBitCount, sizeof(binfo.biBitCount), 1, in);
fwrite(&binfo.biBitCount, sizeof(binfo.biBitCount), 1, out);
fread(&binfo.biCompress, sizeof(binfo.biCompress), 1, in);
fwrite(&binfo.biCompress, sizeof(binfo.biCompress), 1, out); fread(&binfo.biSizeImage, sizeof(binfo.biSizeImage), 1, in);
fwrite(&binfo.biSizeImage, sizeof(binfo.biSizeImage), 1, out); fread(&binfo.biXPelsPerMeter, sizeof(binfo.biXPelsPerMeter), 1, in);
fwrite(&binfo.biXPelsPerMeter, sizeof(binfo.biXPelsPerMeter), 1, out); fread(&binfo.biYPelsPerMeter, sizeof(binfo.biYPelsPerMeter), 1, in);
fwrite(&binfo.biYPelsPerMeter, sizeof(binfo.biYPelsPerMeter), 1, out); fread(&binfo.biClrUsed, sizeof(binfo.biClrUsed), 1, in);
fwrite(&binfo.biClrUsed, sizeof(binfo.biClrUsed), 1, out); fread(&binfo.biClrImportant, sizeof(binfo.biClrImportant), 1, in);
fwrite(&binfo.biClrImportant, sizeof(binfo.biClrImportant), 1, out);
printf("biSize = %ld\n",binfo.biSize);
printf("biWidth = %ld\n",binfo.biWidth);
printf("biHeight = %ld\n",binfo.biHeight);
printf("biPlanes = %d\n",binfo.biPlanes);
printf("biBitCount = %d\n",binfo.biBitCount);
printf("biCompress = %d\n",binfo.biCompress);
printf("biSizeImage = %ld\n",binfo.biSizeImage);
printf("biXpersPerMeter = %ld\n",binfo.biXPelsPerMeter);
printf("biYPersPerMeter = %ld\n",binfo.biYPelsPerMeter);
printf("biClrUsed = %ld\n",binfo.biClrUsed);
printf("biClrImportant = %ld\n", binfo.biClrImportant);
return 0;}
int WritePixtoFile()
{
int i = 0, j = 0;
unsigned long bboffest = bbfile.bfoffBits;
unsigned long boffest = bfile.bfoffBits;
int nBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32);
int bnBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32);
int Y;
unsigned char YY;
int R, G, B;
int RR, GG, BB;
long count = 0;
unsigned char *RGBbuffer = (unsigned char*)malloc(nBufferWide * binfo.biHeight);
unsigned char *bRGBbuffer = (unsigned char*)malloc(bnBufferWide * binfo.biHeight);
fseek(in, bboffest, SEEK_SET); ???这句定位是不是有问题?因为最后保存的图像一片黑.
fread(RGBbuffer, sizeof(unsigned char), nBufferWide * binfo.biHeight, in); for(i = binfo.biWidth -1 ; i >= 0; i--)
{
for(j = binfo.biHeight - 1; j >=0 ; j--)
{ R = (int)(*(RGBbuffer + i*3 + j));
G = (int)(*(RGBbuffer + i*3 + j + 1));
B = (int)(*(RGBbuffer+ i*3 + j + 2)); Y = ((66 * R + 129 * G + 25 * B + 128)>>8) + 16;
YY = (unsigned char) ((Y<0)?0:((Y>255)?255:Y));
RR = YY;
GG = YY;
BB = YY;
printf("YY = %d,", YY);
*(bRGBbuffer + i* 3 +j) = RR;
*(bRGBbuffer + i* 3 +j +1) = RR;
*(bRGBbuffer + i* 3 +j +2) = RR;
//memcpy(bRGBbuffer++, &YY, sizeof(unsigned char));
//printf("YY = %u, count = %ld\n", YY, count);
}
}
fwrite(bRGBbuffer ,1 , bnBufferWide * binfo.biHeight,out);
}int main()
{
open();
init_bmpStruct(); WritePixtoFile();
fclose(in);
fclose(out);
printf("BITMAPFILEHEADER size = %d,BITMAPINFOHEADER size = %d, RGBQUAD size = %d\n ", sizeof(BITMAPFILEHEADER), sizeof(BITMAPINFOHEADER), sizeof(RGBQUAD));
return 1;
}girl.bmp是一个24位的BMP图像,320*240的.
但是保存的gray_girl.bmp,就是一片黑啊~是不是offset定位错了?但是不知道怎么错的.
哪位朋友知道啊.我是新手.点指一下.非常感激!
你在以下代码设置断点,看看他们值的变化? 是否全是0?
RR = YY;
GG = YY;
BB = YY; 另外
int R, G, B;
int RR, GG, BB;
建议声明为BYTE类型否则一下代码不能获取正确的颜色数据
R = (int)(*(RGBbuffer + i*3 + j));
G = (int)(*(RGBbuffer + i*3 + j + 1));
B = (int)(*(RGBbuffer+ i*3 + j + 2));
BYTE就是unsigned char类型
刚改成unsigned char....好像也不行呢~~
1:生成bmp头,包括14字节的笔bmpfileheader与40字节的bmpinfoheader
2:生成256级灰度的调色板
3:读取源文件数据,由转换公式计算生成数据,注意每行要四字节对齐,不够补零
不懂的话可以发邮件到[email protected]
1. 你这个不是真正意义的灰度图像,仍然是24bit的,只是颜色看起来灰了。
2. 24位真彩没有RGBQUAD,这个没用。
3. init_bmpStruct()可以把文件头和信息头一次读来,节省很多代码行。
4. R = (int)(*(RGBbuffer + i*3 + j));
. G = (int)(*(RGBbuffer + i*3 + j + 1));
. B = (int)(*(RGBbuffer+ i*3 + j + 2)); 这3行 R 和 B 应该交换位置,第一个是蓝色
但是上述所有都不是造成你图像全黑的原因。这儿我也看不出你什么地方数据不对了,跟踪调试一下吧。
{
for(j = binfo.biHeight - 1; j >=0 ; j--)
{ =============================
貌似怎么看都怎么别扭..for( i = 0; i < binfo.biHeight; ++i ){
for( j = 0; j < binfo.biWidth; ++j ){
......... // convert
.........
}
}
int nBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32); 这个是处理每行字节被4整除。
Y = ((66 * R + 129 * G + 25 * B + 128)>>8) + 16; 这行是一个灰度转换模型。这都不是新手自己写的。
而BITMAPINFO里的bmiColors[1] <-- =1,而不是256..看看WINGDI.h就知道了.建议你去照搬出来~~hoho~~
unsigned long bboffest = bbfile.bfoffBits;
unsigned long boffest = bfile.bfoffBits;
int nBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32);
int bnBufferWide = 4 * (( binfo.biWidth * 24 + 31 )/ 32);
int Y;
unsigned char YY;
int R, G, B;
int RR, GG, BB;
long count = 0;
unsigned char *RGBbuffer = (unsigned char*)malloc(nBufferWide * binfo.biHeight);
unsigned char *bRGBbuffer = (unsigned char*)malloc(bnBufferWide * binfo.biHeight);
fseek(in, bboffest, SEEK_SET); ???这句定位是不是有问题?因为最后保存的图像一片黑
bbfile什么时候赋值了?貌似读fileheader的是bfile吧..应该是boffset吧
BITMAPFILEHEADER fHdr;
BITMAPINFOHEADER iHdr;
CFile f1,f2;
f1.Open(_T("colorGirl.bmp"),CFile::modeRead);
f2.Open(_T("blackGirl.bmp"),CFile::modeCreate|CFile::modeWrite);
f1.Read(&fHdr,sizeof(BITMAPFILEHEADER));
f2.Write(&fHdr,sizeof(BITMAPFILEHEADER));
f1.Read(&iHdr,sizeof(BITMAPINFOHEADER));
f2.Write(&iHdr,sizeof(BITMAPINFOHEADER)); int y;
int n = f1.GetLength()-sizeof(BITMAPFILEHEADER)-sizeof(BITMAPINFOHEADER);
BYTE * pBuf = new BYTE[n];
f1.Read(pBuf,n);
for(int i=0; i<n/3; i++)
{
y = pBuf[i*3] + pBuf[i*3+1] + pBuf[i*3+2];
y /= 3;
pBuf[i*3] = (BYTE)y;
pBuf[i*3+1] = (BYTE)y;
pBuf[i*3+2] = (BYTE)y;
}
f2.Write(pBuf,n); delete [] pBuf;
f1.Close();
f2.Close();
//1.只能用24位真彩色。
//2.宽度没处理,你的例子可以
//3.灰度变换模型用的是1/3,可以改
一共就这些,运行试试?
我按照你的循环处理每一个像素:
for(int i=0; i<n/3; i++)
{
y = pBuf[i*3] + pBuf[i*3+1] + pBuf[i*3+2];
y /= 3;
pBuf[i*3] = (BYTE)y;
pBuf[i*3+1] = (BYTE)y;
pBuf[i*3+2] = (BYTE)y;
}没有错误了~
但是为什么按照两次循环就不对呢. for(i = binfo.biHeight - 1; i >= 0; i--)
{ for(j = 0; j < binfo.biWidth; j++)
{
R = *(RGBbuffer + i * 3 + j);
G = *(RGBbuffer + i * 3 + j + 1);
B = *(RGBbuffer + i * 3 + j + 2);
Y = ((76 * R + 150 * G + 29 * B + 128) >> 8);
*(bRGBbuffer + i * 3 + j) = Y;
*(bRGBbuffer + i * 3 + j + 1) = Y;
*(bRGBbuffer + i * 3 + j + 2) = Y;
}
}这样处理后的图像,好像只有最下面的几行能隐约看到是图像.上面全是灰灰的~~
R,G,B的值都是有的.这个方法是先将所以像素数据都读到RGBbuffer里面,然后在RGBbuffer处理再都存入bRGBbuffer里,最后写到要保存的图像中.但是如果是每次将一行像素信息读到RGBbuffer里,然后处理后再将这一行数据存入到要保存的图像中,最后,只显示了左边的三分之一的图像,好像有点发绿,颜色不太对,后面大概三分之二的区域又全是灰的.
(这种情况下RGBbuffer的malloc的大小是一行数据的大小, 而不是原来的所有像素数据的大小.)