Biegral Blog

         x264中get_frame_total_yuv函数的作用是计算yuv文件中视频的帧数，定义如下：

int get_frame_total_yuv( hnd_t handle )
{
    yuv_input_t *h = handle;
    int i_frame_total = 0;

    if( !fseek( h->fh, 0, SEEK_END ) )
    {
        uint64_t i_size = ftell( h->fh );
        fseek( h->fh, 0, SEEK_SET );
        i_frame_total = (int)(i_size / ( h->width * h->height * 3 / 2 )); // yuv420
    }

    return i_frame_total;
}

      为了更加简便起见，本人给出下列程序：（foreman_qcif.yuv文件有300帧）

#include <stdio.h>

// yuv文件结构体
typedef struct yuvFile
{
	FILE *fp;
	int width;
	int height;
}YUVFILE;

// 获取yuv文件的帧数
int getFrameTotalYuv(YUVFILE file)
{
    int frameTotal;
	int size;

    if( !fseek( file.fp, 0, SEEK_END ) )
    {
        size = ftell( file.fp );
        frameTotal = size/( file.width * file.height * 3 / 2 ); // yuv420
    }

    return frameTotal;
}

int main()
{
	YUVFILE file;

	file.fp = fopen("foreman_qcif.yuv", "rb");
	file.width = 176;
	file.height = 144;

	printf("%d\n", getFrameTotalYuv(file));

	return 0;
}

      结果为:300