图像读写
//include header
#include <opencv2/imgcodecs.hpp>
/**
Currently, the following file formats are supported:
Windows bitmaps - *.bmp, *.dib (always supported)
JPEG files - *.jpeg, *.jpg, *.jpe (see the Note section)
JPEG 2000 files - *.jp2 (see the Note section)
Portable Network Graphics - *.png (see the Note section)
WebP - *.webp (see the Note section)
Portable image format - *.pbm, *.pgm, *.ppm *.pxm, *.pnm (always supported)
Sun rasters - *.sr, *.ras (always supported)
TIFF files - *.tiff, *.tif (see the Note section)
OpenEXR Image files - *.exr (see the Note section)
Radiance HDR - *.hdr, *.pic (always supported)
Raster and Vector geospatial data supported by GDAL (see the Note section)
*/
Mat cv::imread ( const String & filename,
int flags = IMREAD_COLOR
);
bool cv::imwrite ( const String & filename,
InputArray img,
const std::vector< int > & params = std::vector< int >()
);
图像ROI选取
cv::Mat roi=frame(cv::Rect(x, y, roi_WIDTH, roi_HEIGHT));
图像多通道分离合并
//include header
#include <opencv2/core.hpp>
/**
void cv::split ( const Mat & src,
Mat * mvbegin
);
void cv::merge ( const Mat * mv,
size_t count,
OutputArray dst
);
*/
cv::Mat src,dst;
std::vector<cv::Mat> imgplanes;
cv::split(src,imgplanes);
cv::merge(imgplanes,imgplanes.size(),dst);
图像串联组合
cv::Mat img_encode, img_encode1, img_encode2;
//水平串联
cv::hconcat(img_camera[0], img_camera[1], img_encode1);
cv::hconcat(img_camera[2], img_camera[3], img_encode2);
//垂直串联
cv::vconcat(img_encode1, img_encode2, img_encode);
Camera实时数据/视频回放
Camera实时数据
#include <opencv2/core.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/highgui.hpp>
#include <iostream>
#include <stdio.h>
using namespace cv;
using namespace std;
int main(int, char**)
{
Mat frame;
//--- INITIALIZE VIDEOCAPTURE
VideoCapture cap;
// open the default camera using default API
// cap.open(0);
// OR advance usage: select any API backend
int deviceID = 0; // 0 = open default camera
int apiID = cv::CAP_ANY; // 0 = autodetect default API
// open selected camera using selected API
cap.open(deviceID, apiID);
// check if we succeeded
if (!cap.isOpened()) {
cerr << "ERROR! Unable to open camera\n";
return -1;
}
//--- GRAB AND WRITE LOOP
cout << "Start grabbing" << endl
<< "Press any key to terminate" << endl;
for (;;)
{
// wait for a new frame from camera and store it into 'frame'
cap.read(frame);
// check if we succeeded
if (frame.empty()) {
cerr << "ERROR! blank frame grabbed\n";
break;
}
// show live and wait for a key with timeout long enough to show images
imshow("Live", frame);
if (waitKey(5) >= 0)
break;
}
// the camera will be deinitialized automatically in VideoCapture destructor
return 0;
}
视频回放
cv::VideoCapture capture(videoPath);
for (;;)
{
capture >> frame;
}