在PP中将PPM从RGB转换为HSL

Question

我的学术课程需要RGB图像文件中的直方图均衡帮助。

我检查了我之前关于直方图均衡的代码示例，但我没有找到任何有关此问题的线索。我从未练习过直方图均衡示例，即RGB图像。

图像是PPM文件。因此，我们需要将文件从RGB转换为YCbCr，从RGB转换为HSI。

然后，我们需要在图像为YCbCr和HSI格式时进行直方图均衡。

之后，我们需要再次将PPM文件转换为RGB格式。而已。

*void write_image function is writing the data to the pnr.ppm*

*void get_image_data function is getting the image that is mandrill1.ppm*

我们只需要指定代码：

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#include<math.h>
#include<ctype.h>
#include<string.h>
#include <fcntl.h>
#include <malloc.h>
#include <math.h>
#define PI 3.1415926535897932384626433832795
struct ppm_header
{
   char pgmtype1;
   char pgmtype2;
   int pwidth;
   int pheight;
   int pmax;
};
struct ppm_file
{
   struct ppm_header *pheader;
   unsigned char *rdata,*gdata,*bdata;
};

void get_image_data(char *filename,struct ppm_file *image);
void write_image(char *filename,struct ppm_file *image);

main()
{
  struct ppm_file resim;
  get_image_data("mandrill1.ppm",&resim);


  printf("pgmtype...=%c%c\n",resim.pheader->pgmtype1,resim.pheader->pgmtype2);
  printf("width...=%d\n",resim.pheader->pwidth);
  printf("height...=%d\n",resim.pheader->pheight);
  printf("max gray level...=%d\n",resim.pheader->pmax);

  write_image("pnr.ppm",&resim);
  return 0;
}

void write_image(char *filename,struct ppm_file *image) 
{
    FILE *fp;
    int i,max=0;
    fp=fopen(filename,"wb");
    fputc(image->pheader->pgmtype1,fp);
    fputc(image->pheader->pgmtype2,fp);
    fputc('\n',fp);
    fprintf(fp,"%d %d\n",image->pheader->pwidth,image->pheader->pheight);
    fprintf(fp,"%d\n",255/*max*/);
    for(i=0;i<image->pheader->pwidth*image->pheader->pheight;i++)
    {
        fwrite(&image->rdata[i],1,1,fp);
        fwrite(&image->gdata[i],1,1,fp);
        fwrite(&image->bdata[i],1,1,fp);
    }
    fclose(fp);
}
void get_image_data(char *filename, struct ppm_file *image )
{
    FILE* fp;
    int i=0;
    char temp[256];
    image->pheader=(struct ppm_header *)malloc(sizeof(struct ppm_header));
    fp = fopen(filename, "rb" );
    if (fp==NULL)
    {
        printf("Dosya acilamadi: %s.\n\n", filename);
        exit(1);
    }
    printf ("Okunan PPM dosyasi : %s...\n", filename);
    fscanf (fp, "%s", temp);
    if (strcmp(temp, "P6") == 0)
    {
        image->pheader->pgmtype1=temp[0];
        image->pheader->pgmtype2=temp[1];
        fscanf (fp, "%s", temp);
        if (temp[0]=='#')
        {

            while(fgetc(fp)!='\n');
            fscanf (fp, "%d %d\n",&image->pheader->pwidth,&image->pheader->pheight);
            fscanf (fp, "%d\n", &image->pheader->pmax);

        }
        else
        {
            sscanf (temp, "%d", &image->pheader->pwidth);
            fscanf (fp, "%d", &image->pheader->pheight);
            fscanf (fp, "%d", &image->pheader->pmax);
        }
        image->rdata=(unsigned char *)malloc(image->pheader->pheight*image->pheader->pwidth*sizeof(unsigned char));
        image->gdata=(unsigned char *)malloc(image->pheader->pheight*image->pheader->pwidth*sizeof(unsigned char));
        image->bdata=(unsigned char *)malloc(image->pheader->pheight*image->pheader->pwidth*sizeof(unsigned char));
        if (image->rdata==NULL) printf("bellek problemi...\n");
        for(i=0;i<image->pheader->pwidth*image->pheader->pheight;i++)
        {
            fread(&image->rdata[i],1,1,fp);
            fread(&image->gdata[i],1,1,fp);
            fread(&image->bdata[i],1,1,fp);
        }
    }
    else
    {
        printf ("\nHata Resim dosyasi PGM P6 formatinda degil");
        exit(1);
    }
    fclose(fp);
}