分离YUV420P像素数据中的Y、U、V分量【转载】

原文链接：链接
雷神博客：链接

只做一些修改，是为转载。

• 增加头文件
• 并入main函数
• 修改输出文件后缀名

在调用时，填写的四个参数
simplest_yuv420_split(“foreman_qcif.yuv”, 176, 144, 300);

“foreman_qcif.yuv”：yuv文件名
176：文件width
144：文件height
300：frame numbers

/**
 * Split Y, U, V planes in YUV420P file.
 * @param url  Location of Input YUV file.
 * @param w    Width of Input YUV file.
 * @param h    Height of Input YUV file.
 * @param num  Number of frames to process.
 *
 */
#include <stdio.h>
#include <stdlib.h>
int simplest_yuv420_split(const char *url, int w, int h, int num) {
	FILE *fp = fopen(url, "rb+");
	//额外修改三个分量输出文件的后缀
	FILE *fp1 = fopen("output_420_y.yuv", "wb+");
	FILE *fp2 = fopen("output_420_u.yuv", "wb+");
	FILE *fp3 = fopen("output_420_v.yuv", "wb+");

	/*  orginal code
	FILE *fp1=fopen("output_420_y.y","wb+");
	FILE *fp2=fopen("output_420_u.y","wb+");
	FILE *fp3=fopen("output_420_v.y","wb+");
	*/

	unsigned char *pic = (unsigned char *)malloc(w*h * 3 / 2);

	for (int i = 0; i < num; i++) {

		fread(pic, 1, w*h * 3 / 2, fp);
		//Y
		fwrite(pic, 1, w*h, fp1);
		//U
		fwrite(pic + w * h, 1, w*h / 4, fp2);
		//V
		fwrite(pic + w * h * 5 / 4, 1, w*h / 4, fp3);
	}

	free(pic);
	fclose(fp);
	fclose(fp1);
	fclose(fp2);
	fclose(fp3);

	return 0;
}

int main()
{
	simplest_yuv420_split("foreman_qcif.yuv", 176, 144, 300);
	return 0;
}

之所以把输出文件后缀修改为.yuv是方便使用YUView打开