把yuv422 轉為rgb32 ，利用framebuffer 顯示
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/videodev2.h> //v4l2 頭文件
#include <string.h>
#include <sys/mman.h>
#include <linux/fb.h>#define pic_width 1920
#define pic_heigth 1080
#define pic_path "/home/wzpc/Pictures/my.yuv"static int color1=0;
static int color2=0;
static int sp[pic_width*pic_heigth];
static struct fb_var_screeninfo var;int main(void)
{FILE *f=fopen(pic_path,"r+b");if(f==NULL){puts("file error");exit(-1);}fseek(f,0,SEEK_END);int len=ftell(f);fseek(f,0,SEEK_SET);int fd=fileno(f);char *p1=mmap(NULL,len,PROT_READ,MAP_SHARED,fd,0);char (*p)[4]=(char (*)[4])p1; // p[][0]=Y p[][1]=U p[][2]=Y p[][3]=V//R = Y + 1.4075 *（V-128）//G = Y – 0.3455 *（U –128） – 0.7169 *（V –128） // B = Y + 1.779 *（U – 128)int t=0;int u=0;while(1){if(4*t>=len){break;}int Y1=(unsigned char)p[t][0];if((4*t+1)>=len){break;}int U=(unsigned char)p[t][1];if((4*t+2)>=len){break;}int Y2=(unsigned char)p[t][2];if((4*t+3)>=len){break;}int V=(unsigned char)p[t][3];//------------------------------------------------- int B0=Y1+1.779*(U-128);if(B0>255) B0=255;if(B0<0) B0=0;int G0=Y1-0.3455*(U-128)-0.7169*(V-128);if(G0>255) G0=255;if(G0<0) G0=0;int R0=Y1+1.4075*(V-128);if(R0>255) R0=255;if(R0<0) R0=0;int B1=Y2+1.779*(U-128);if(B1>255) B1=255;if(B1<0) B1=0;int G1=Y2-0.3455*(U-128)-0.7169*(V-128);if(G1>255) G1=255;if(G1<0) G1=0;int R1=Y2+1.4075*(V-128);if(R1>255) R1=255;if(R1<0) R1=0;color1=(R0<<16)|(G0<<8)|B0;color2=(R1<<16)|(G1<<8)|B1;sp[u]=color1;sp[u+1]=color2;t++;u=u+2;}munmap(p1,len);puts("yuyv over");//--------------------------------int fd_fb = open("/dev/fb0", O_RDWR);if (fd_fb < 0){puts("/dev/fb0 error");return -1;}if (ioctl(fd_fb, FBIOGET_VSCREENINFO, &var)){puts("ioctl error");return -1;}// unsigned int pixel_width = var.bits_per_pixel / 8; //deepin=32int screen_size = var.xres * var.yres * var.bits_per_pixel / 8;unsigned char *fb_base = mmap(NULL, screen_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_fb, 0);if (fb_base == NULL){puts("mmap error");return -1;}memset(fb_base,0, screen_size);int zz=0;for(int a=0;a<var.yres;a++){for(int b=0;b<var.xres;b++){unsigned int (*p)[var.xres]=(unsigned int (*)[var.xres])fb_base;p[a][b]=sp[zz]; //sp[zz]zz++;}}munmap(fb_base, screen_size);close(fd_fb);puts("over");return 0;
}
