dct.c

基于fftw的dct程序

#include <stdlib.h> 
#include <stdio.h>
#include <string.h> 
#include <SDL.h> 
#include <fftw3.h>
#include <sys/types.h> 
#include <sys/stat.h> 
#include <fcntl.h> 
#include <errno.h>
#include <unistd.h>
#include <pthread.h>
#include <semaphore.h>
#include <sys/ipc.h> 
#define N4 6
#define N3 3
#define N2 2
#define N1 1
#define W 768
#define H 432 
#define FILENAME "source.yuv" 
#define OUTPUT "SVC.yuv" 
unsigned char data[H*W*3/2];
unsigned char data3[H*W*27/128];
int flag=0;
int main()
{
   FILE *f,*output; 
   double *in,*out;
   unsigned char *point,*point1; 
   fftw_plan p1,p2,p3,p4,p14;
   int i,j,a,yblock,uvblock,count_yblk,count_uvblk,pix,piy,gop,pix3,piy3,qt;
   if ((f = fopen(FILENAME, "rb")) == NULL) { 
        perror("fopen"); 
        exit(1); 
         }
   if ((output = fopen(OUTPUT, "wb")) == NULL) { 
        perror("fopen"); 
        exit(1); 
         }
               
   in =(double *)fftw_malloc(sizeof(double)*N4*N4);
   out =(double *)fftw_malloc(sizeof(double)*N4*N4);
   p4=fftw_plan_r2r_2d(N4, N4, in, out, FFTW_REDFT10, FFTW_REDFT10, FFTW_ESTIMATE);
   p14=fftw_plan_r2r_2d(N4, N4, out, in, FFTW_REDFT01, FFTW_REDFT01, FFTW_ESTIMATE);
   p3=fftw_plan_r2r_2d(N3, N3, out, in, FFTW_REDFT01, FFTW_REDFT01, FFTW_ESTIMATE);
   p2=fftw_plan_r2r_2d(N2, N2, out, in, FFTW_REDFT01, FFTW_REDFT01, FFTW_ESTIMATE);
   p1=fftw_plan_r2r_2d(N1, N1, out, in, FFTW_REDFT01, FFTW_REDFT01, FFTW_ESTIMATE);
   yblock=H*W/64;
   uvblock=yblock>>2;
   count_yblk=W>>3;
   count_uvblk=count_yblk>>1;
   for(gop=0;gop<300;gop++){
       if(fread(data, H*W*3/2, 1, f) != 1){          
          return;
            }
         /* Y component DCT*/
       pix=piy=pix3=piy3=0;   
       for(a=0;a<yblock;a++){       
                             
            
           fftw_execute(p4);
          
                 
              }
       /* UV component DCT*/
       pix=piy=pix3=piy3=0;   
       for(a=0;a<uvblock;a++){       
               
            
           fftw_execute(p4);
         
           fftw_execute(p4);
         

           pix+=8;
           pix3+=3;
           if((a+1)%count_uvblk==0){
              pix=0;
              pix3=0;
              piy+=8; 
              piy3+=3; 
               }         
              }
           
       if(fwrite(data3, H*W*27/128, 1, output) != 1){          
          return;
            } 
      }
   fftw_destroy_plan(p4);
   fftw_destroy_plan(p3);
   fftw_free(in);
   fftw_free(out);  
}