opencv4.1.1(1)视频捕获显示

本例程功能捕获本地文件或者摄像头图像，获取对应图像信息以及图像缩放然后显示。

#include
#include
#include
#include

using namespace cv;
using namespace std;


//#define USE_CAMERA //使用摄像头
#define USE_VIDEO
void main(int argc, char** argv)
{
#ifdef USE_VIDEO
	Mat mCamVideo;
	VideoCapture mCamCap("./1080P.h264");
	int brightness = mCamCap.get(cv::CAP_PROP_BRIGHTNESS);
	int contrast = mCamCap.get(cv::CAP_PROP_CONTRAST);
	int saturation = mCamCap.get(cv::CAP_PROP_SATURATION);
	int hue = mCamCap.get(cv::CAP_PROP_HUE);
	int gain = mCamCap.get(cv::CAP_PROP_GAIN);
	int exposure = mCamCap.get(cv::CAP_PROP_EXPOSURE);
	int white_balance = mCamCap.get(cv::CAP_PROP_WHITE_BALANCE_BLUE_U);

	int width = mCamCap.get(cv::CAP_PROP_FRAME_WIDTH);
	int heigh = mCamCap.get(cv::CAP_PROP_FRAME_HEIGHT);
	int fps = mCamCap.get(cv::CAP_PROP_FPS);


	std::cout << "---------------------------------------------" << endl;
	std::cout << "宽：" << width << endl;
	std::cout << "高：" << heigh << endl;
	std::cout << "fps：" << fps << endl;
	std::cout << "---------------------------------------------" << endl;

	namedWindow("文件");
	resizeWindow("文件",1280,720);
	moveWindow("文件",100,0);
	while (mCamCap.isOpened())
	{
		double pos_msec = mCamCap.get(cv::CAP_PROP_POS_MSEC);
		double pos_frame = mCamCap.get(cv::CAP_PROP_POS_FRAMES);
		double pos_avi_ratio = mCamCap.get(cv::CAP_PROP_POS_AVI_RATIO);
		cout << "---------------------------------------------" << endl;
		cout << "视频文件中当前位置(ms):" << pos_msec << endl;
		cout << "从0开始下一帧的索引:" << pos_frame << endl;
		cout << "视频中的相对位置(范围为0.0到1.0):" << pos_avi_ratio << endl;
		cout << "---------------------------------------------" << endl;
		mCamCap >> mCamVideo;
		cv::Size mSize;
		mSize.width = 1280;
		mSize.height = 720;
		
		cv::resize(mCamVideo, mCamVideo, mSize);
		if (mCamVideo.empty())
		{
			break;
		}
		else
		{
			imshow("文件", mCamVideo);
		}
		waitKey(1);
	}
#else
	Mat mCamVideo;
	VideoCapture mCamCap(0);
	int brightness = mCamCap.get(cv::CAP_PROP_BRIGHTNESS);
	int contrast = mCamCap.get(cv::CAP_PROP_CONTRAST);
	int saturation = mCamCap.get(cv::CAP_PROP_SATURATION);
	int hue = mCamCap.get(cv::CAP_PROP_HUE);
	int gain = mCamCap.get(cv::CAP_PROP_GAIN);
	int exposure = mCamCap.get(cv::CAP_PROP_EXPOSURE);
	int white_balance = mCamCap.get(cv::CAP_PROP_WHITE_BALANCE_BLUE_U);

	int width = mCamCap.get(cv::CAP_PROP_FRAME_WIDTH);
	int heigh = mCamCap.get(cv::CAP_PROP_FRAME_HEIGHT);
	int fps= mCamCap.get(cv::CAP_PROP_FPS);

	std::cout << "---------------------------------------------" << endl;
	std::cout << "摄像头亮度：" << brightness << endl;
	std::cout << "摄像头对比度：" << contrast << endl;
	std::cout << "摄像头饱和度：" << saturation << endl;
	std::cout << "摄像头色调：" << hue << endl;
	std::cout << "摄像头增益：" << gain << endl;
	std::cout << "摄像头曝光度：" << exposure << endl;
	std::cout << "摄像头白平衡：" << white_balance << endl;
	std::cout << "---------------------------------------------" << endl;
	std::cout << "宽：" << width << endl;
	std::cout << "高：" << heigh << endl;
	std::cout << "fps：" << fps << endl;
	std::cout << "---------------------------------------------" << endl;

	namedWindow("摄像头");

	while (mCamCap.isOpened())
	{
		mCamCap>> mCamVideo;
		imshow("摄像头", mCamVideo);
		waitKey(1);
	}
#endif
	mCamCap.release();
	destroyAllWindows();
	return ;
}