RGB 2 YUV 亮度与对比度调节

从BMP图中读取RGB值并转化成YUV

BYTE *** rgb2yuv(const char *filename){  BYTE ***image;  FILE *file;  int i, j, k;  int biBitCount, offset;  int *x;  /*    RGBQUAD aColors[];    BYTE aBitmapBits[];  */  if (!(file=fopen(filename,"rb")))     {      printf("Cannot open file %s.\n", filename);      return 0;    }  fread(&bmfhdr.bfType, sizeof(WORD), 1, file);  fread(&bmfhdr.bfSize, sizeof(DWORD), 1, file);  fread(&bmfhdr.bfReserved1, sizeof(WORD), 1, file);  fread(&bmfhdr.bfReserved2, sizeof(WORD), 1, file);  fread(&bmfhdr.bfOffBits, sizeof(DWORD), 1, file);  fread(&bmihdr.biSize, sizeof(DWORD), 1, file);  fread(&bmihdr.biWidth, sizeof(LONG), 1, file);  fread(&bmihdr.biHeight, sizeof(LONG), 1, file);  fread(&bmihdr.biPlanes, sizeof(WORD), 1, file);  fread(&bmihdr.biBitCount, sizeof(WORD), 1, file);  fread(&bmihdr.biCompression, sizeof(DWORD), 1, file);  fread(&bmihdr.biSizeImage, sizeof(DWORD), 1, file);  fread(&bmihdr.biXPelsPerMeter, sizeof(LONG), 1, file);  fread(&bmihdr.biYPelsPerMeter, sizeof(LONG), 1, file);  fread(&bmihdr.biClrUsed, sizeof(DWORD), 1, file);  fread(&bmihdr.biClrImportant, sizeof(DWORD), 1, file);  //fread(&bmfhdr,sizeof(bmfhdr),1,file);  //fread(&bmihdr,sizeof(bmihdr),1,file);  printf("| biBitCount: %d\n", bmihdr.biBitCount);  if (bmihdr.biBitCount == 1) {    RGBQUAD aColors[2];    for (i=0; i<2; i++) {      fread(&aColors[i].rgbBlue, sizeof(BYTE), 1, file);      fread(&aColors[i].rgbGreen, sizeof(BYTE), 1, file);      fread(&aColors[i].rgbRed, sizeof(BYTE), 1, file);      fread(&aColors[i].rgbReserved, sizeof(BYTE), 1, file);      printf("| rgbBlue: %d\t rgbGreen: %d\t rgbRed: %d\t rgbReserved: %d\n", aColors[i].rgbBlue, aColors[i].rgbGreen, aColors[i].rgbRed, aColors[i].rgbReserved);    }  } else if (bmihdr.biBitCount == 8) {    RGBQUAD aColors[256];    for (i=0; i<8; i++) {      fread(&aColors[i].rgbBlue, sizeof(BYTE), 1, file);      fread(&aColors[i].rgbGreen, sizeof(BYTE), 1, file);      fread(&aColors[i].rgbRed, sizeof(BYTE), 1, file);      fread(&aColors[i].rgbReserved, sizeof(BYTE), 1, file);      printf("| rgbBlue: %d\t rgbGreen: %d\t rgbRed: %d\t rgbReserved: %d\n", aColors[i].rgbBlue, aColors[i].rgbGreen, aColors[i].rgbRed, aColors[i].rgbReserved);    }  } else if (bmihdr.biBitCount == 24) {    printf(" It's rgb bmp image without palette.\n");  } else {    printf("Something wrong with biBitCount of image %s.\n", filename);    return 0;  }  printf("+------------------+\n");  /* display bmp image attributes. */  biBitCount = bmihdr.biBitCount;  if (biBitCount == 1) {    printf("%s is Binary image.\n", filename);  } else if (biBitCount == 8) {    printf("%s is Gray-Level or Indexed image.\n", filename);  } else if (biBitCount == 24) {    printf("%s is RGB image.\n", filename);  } else {      printf("Something wrong with biBitCount of image %s.\n", filename);  }  /* width and height of bmp image. */  width = bmihdr.biWidth;  height = bmihdr.biHeight;  level = 3; /* for RGB only */  /* malloc for 3-D array ***image and 1-D array *x. */  image = (BYTE ***)malloc(height*sizeof(BYTE **));  for (i=0; i<height; i++)    image[i] = (BYTE **)malloc(width*sizeof(BYTE *));  for(i=0; i<height; i++)    for (j=0; j<width; j++)      image[i][j] = (BYTE *)malloc(level*sizeof(BYTE));  x = (int *)malloc(level*sizeof(int));  /* initialize 3-D array ***image and 1-D array *x. */  for (i=0; i<height; i++)    for (j=0; j<width; j++)      for (k=0; k<level; k++)        image[i][j][k] = 0;  for (k=0; k<level; k++)    x[k] = 0;  /* read pixel from file to array image. */  /*    bmihdr.biBitCount = 1  -> Binary image.    bmihdr.biBitCount = 8  -> Gray-Level or Indexed image.    bmihdr.biBitCount = 24 -> RGB image.  */  if ((bmihdr.biBitCount == 1) || (bmihdr.biBitCount == 8)) {    offset = bmfhdr.bfOffBits - 54;    fseek(file, offset, SEEK_CUR);    for (i=height-1; i>=0; i--) {      for (j=0; j<width; j++) {        image[i][j][0] = fgetc(file);      }    }  } else if (bmihdr.biBitCount == 24) {    for (i=height-1; i>=0; i--) {      for (j=0; j<width; j++)        for (k=level-1; k>=0; k--)          image[i][j][k] = fgetc(file);      /*        if(3*width%4 != 0)        fseek(file, 4-width*3%4, SEEK_CUR);      */    }  } else {    printf("Something wrong with biBitCount of image %s.\n", filename);    return 0;  }    printf("==================oldimage===================\n");    for (int i = 0; i < height; ++i)  {       for (int j = 0; j < width; ++j)      {        //Y[i][j] += (255 -maxY)/5;        printf("%d %d %d *", image[i][j][0],image[i][j][1],image[i][j][2]);      }      printf("\n");  }  Y = (BYTE **) malloc(height*sizeof(BYTE *));  U = (char **) malloc(height*sizeof(char *));  V = (char **) malloc(height*sizeof(char *));  for (int i = 0; i < height; ++i)  {       Y[i] = (BYTE *) malloc(width*sizeof(BYTE));      U[i] = (char *) malloc(width*sizeof(char));      V[i] = (char *) malloc(width*sizeof(char));      for (int j = 0; j < width; ++j)      {        Y[i][j] = (BYTE)(0.299*image[i][j][0] + 0.587*image[i][j][1] + 0.114*image[i][j][2]);        U[i][j] = (BYTE)(-0.147*image[i][j][0] -0.289*image[i][j][1] + 0.435*image[i][j][2]);        V[i][j] = (BYTE)(0.615*image[i][j][0] -0.515*image[i][j][1] + -0.100*image[i][j][2]);        if (maxY < Y[i][j])        {            maxY = Y[i][j];            /* code */        }        if (minY > Y[i][j])        {            minY = Y[i][j];            /* code */        }      }  }  fclose(file);  return image;}

调节对比度，输出灰度图

int toGray(char * filename){  printf("==================newY===================\n");    BYTE** newY;  newY = (BYTE **) malloc(height*sizeof(BYTE *));  for (int i = 0; i < height; ++i)  {       newY[i] = (BYTE *) malloc(width*sizeof(BYTE));      for (int j = 0; j < width; ++j)      {        newY[i][j] = (Y[i][j]-minY)*1.0/(maxY - minY)*255;      }  }  FILE * file2;  printf("==================Gray-Level-writing===================\n");  if (!(file2=fopen("test.bmp","wb")))     {      printf("Cannot open file %s.\n", filename);      return(7);    }  fwrite(&bmfhdr.bfType, sizeof(WORD), 1, file2);  fwrite(&bmfhdr.bfSize, sizeof(DWORD), 1, file2);  fwrite(&bmfhdr.bfReserved1, sizeof(WORD), 1, file2);  fwrite(&bmfhdr.bfReserved2, sizeof(WORD), 1, file2);  fwrite(&bmfhdr.bfOffBits, sizeof(DWORD), 1, file2);  fwrite(&bmihdr.biSize, sizeof(DWORD), 1, file2);  fwrite(&bmihdr.biWidth, sizeof(LONG), 1, file2);  fwrite(&bmihdr.biHeight, sizeof(LONG), 1, file2);  fwrite(&bmihdr.biPlanes, sizeof(WORD), 1, file2);  fwrite(&bmihdr.biBitCount, sizeof(WORD), 1, file2);  fwrite(&bmihdr.biCompression, sizeof(DWORD), 1, file2);  fwrite(&bmihdr.biSizeImage, sizeof(DWORD), 1, file2);  fwrite(&bmihdr.biXPelsPerMeter, sizeof(LONG), 1, file2);  fwrite(&bmihdr.biYPelsPerMeter, sizeof(LONG), 1, file2);  fwrite(&bmihdr.biClrUsed, sizeof(DWORD), 1, file2);  fwrite(&bmihdr.biClrImportant, sizeof(DWORD), 1, file2);  for (int i=height-1; i>=0; i--) {      for (int j=0; j<width; j++)        for (int k=level-1; k>=0; k--)            fwrite(&Y[i][j],sizeof(BYTE),1,file2);          //image[i][j][k] = fgetc(file);  }  fclose(file2);  return 0;}

调节亮度，输出RGB图

int ChangeLuminance(int delta, const char *filename, BYTE ***image){  int temp=0;  printf("==================newimage===================\n");  for (int i = 0; i < height; ++i)  {       for (int j = 0; j < width; ++j)      {        Y[i][j] =Y[i][j] > 255-delta?255:Y[i][j] < -delta?0:Y[i][j]+delta;                      temp = (1.0*Y[i][j] + 0*U[i][j] + 1.1398*V[i][j]);        image[i][j][0] = temp>255?255:temp<0?0:temp;        temp = (0.9996*Y[i][j] -0.3954*U[i][j] -0.5805*V[i][j]);        image[i][j][1] = temp>255?255:temp<0?0:temp;        temp= (1.0020*Y[i][j] + 2.0361*U[i][j] -0.0005*V[i][j]);        image[i][j][2] = temp>255?255:temp<0?0:temp;        printf("%d %d %d *", image[i][j][0],image[i][j][1],image[i][j][2]);      }      printf("\n");  }  FILE * file2;  printf("==========================================\n");  if (!(file2=fopen(filename,"wb")))     {      printf("Cannot open file %s.\n", filename);      return(7);    }      fwrite(&bmfhdr.bfType, sizeof(WORD), 1, file2);      fwrite(&bmfhdr.bfSize, sizeof(DWORD), 1, file2);      fwrite(&bmfhdr.bfReserved1, sizeof(WORD), 1, file2);      fwrite(&bmfhdr.bfReserved2, sizeof(WORD), 1, file2);      fwrite(&bmfhdr.bfOffBits, sizeof(DWORD), 1, file2);      fwrite(&bmihdr.biSize, sizeof(DWORD), 1, file2);      fwrite(&bmihdr.biWidth, sizeof(LONG), 1, file2);      fwrite(&bmihdr.biHeight, sizeof(LONG), 1, file2);      fwrite(&bmihdr.biPlanes, sizeof(WORD), 1, file2);      fwrite(&bmihdr.biBitCount, sizeof(WORD), 1, file2);      fwrite(&bmihdr.biCompression, sizeof(DWORD), 1, file2);      fwrite(&bmihdr.biSizeImage, sizeof(DWORD), 1, file2);      fwrite(&bmihdr.biXPelsPerMeter, sizeof(LONG), 1, file2);      fwrite(&bmihdr.biYPelsPerMeter, sizeof(LONG), 1, file2);      fwrite(&bmihdr.biClrUsed, sizeof(DWORD), 1, file2);      fwrite(&bmihdr.biClrImportant, sizeof(DWORD), 1, file2);  for (int i=height-1; i>=0; i--) {      for (int j=0; j<width; j++)        for (int k=level-1; k>=0; k--)            fwrite(&image[i][j][k],sizeof(BYTE),1,file2);  }  fclose(file2);  return(0);}