c/c++使用ffmepg库获取视频信息(宽高时长等)

//引入ffmpeg的头文件和lib，自己处理好库的路径
extern "C"
{
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libswscale/swscale.h"
#include "libavutil/imgutils.h"
};

#pragma comment(lib,"avcodec.lib")
#pragma comment(lib,"avdevice.lib")
#pragma comment(lib,"avfilter.lib")
#pragma comment(lib,"avformat.lib")
#pragma comment(lib,"avutil.lib")
#pragma comment(lib,"postproc.lib")
#pragma comment(lib,"swresample.lib")
#pragma comment(lib,"swscale.lib")

int _tmain(int argc, _TCHAR* argv[])
{
	//注册复用器，编码器等
	av_register_all();

	AVFormatContext *formatContext = NULL;

	// 打开视频文件
	if (avformat_open_input(&formatContext, "E:\\TestCode\\TestMfc\\big_buck_bunny.mp4", NULL, NULL) != 0) {
		printf("无法打开视频文件\n");
		return -1;
	}

	// 查找视频文件中的流信息
	if (avformat_find_stream_info(formatContext, NULL) < 0) {
		printf("无法查找视频流信息\n");
		return -1;
	}

	int videoStreamIndex = -1;
	AVCodecParameters *codecParameters = NULL;

	// 查找视频流
	for (int i = 0; i < formatContext->nb_streams; i++) {
		if (formatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
			videoStreamIndex = i;
			codecParameters = formatContext->streams[i]->codecpar;
			break;
		}
	}

	if (videoStreamIndex == -1) {
		printf("无法查找视频流\n");
		return -1;
	}

	// 获取视频时长
	int64_t duration = formatContext->streams[videoStreamIndex]->duration;
	AVRational timeBase = formatContext->streams[videoStreamIndex]->time_base;
	int durationInSeconds = duration * timeBase.num / timeBase.den;

	int nWidth = codecParameters->width;
	int nHeight = codecParameters->height;

	printf("视频时长: %d 秒\n", durationInSeconds);

	// 关闭视频文件
	avformat_close_input(&formatContext);
	return 0;
}