// The processing loop where images are retrieved, tags detected,
// and information about detections generated
void loop() {
cv::Mat image;
cv::Mat image_gray;
int frame = 0;
double last_t = tic();
while (true) {
// capture frame
Camera.grab();
Camera.retrieve ( image);
processImage(image, image_gray);
// print out the frame rate at which image frames are being processed
frame++;
if (frame % 10 == 0) {
double t = tic();
cout << " " << 10./(t-last_t) << " fps" << endl;
last_t = t;
}
// exit if any key is pressed
if (cv::waitKey(1) >= 0) break;
}
}
int32_t FindLineCenter(raspicam::RaspiCam_Cv &Camera, int32_t nTick, int32_t &nCenterX, int32_t &nCenterY)
{
cv::Mat image;
char szFilename[100] = "";
char szOriFilename[100];
#if PRESERVEROI
char szOriROIFilename[100];
cv::Mat roiImgPreserve;
#endif
cv::Rect roi(0, 190, CAMERA_IMG_WIDTH, 100);
cv::Mat roiImg, erodeElmt, dilateElmt;
int thVal = IMGTHRESHOLD;
vector<vector<cv::Point> > contours;
vector<cv::Vec4i> hierarchy;
int nRet = -1;
nCenterX = CAMERA_IMG_WIDTH / 2;
nCenterY = CAMERA_IMG_HEIGHT / 2;
{
try {
Camera.grab();
Camera.retrieve(image);
image(roi).copyTo(roiImg);
#if PRESERVEROI
roiImg.copyTo(roiImgPreserve);
#endif
} catch (cv::Exception& e)
{
const char* err_msg = e.what();
std::cout << "exception caught: " << err_msg << std::endl;
}
#if THRESHOLDIMAGE
//printf("threshold image\n");
cv::threshold(roiImg, roiImg, thVal, 255, cv::THRESH_BINARY);
//printf("bitwise_not image\n");
cv::bitwise_not(roiImg, roiImg); // negative image
erodeElmt = cv::getStructuringElement(cv::MORPH_RECT, cv::Size(3, 3));
dilateElmt = cv::getStructuringElement(cv::MORPH_RECT, cv::Size(5, 5));
//printf("erode image\n");
cv::erode(roiImg, roiImg, erodeElmt);
//printf("dilate image\n");
cv::dilate(roiImg, roiImg, dilateElmt);
#endif
#if TESTROI
{
sprintf(szFilename, "roi_image%d.png", nTick);
sprintf(szOriFilename, "image%d.png", nTick);
try {
//cv::drawContours(roiImg, contours, s, cv::Scalar(255, 255, 255), 2, 8, hierarchy, 0, cv::Point() );
cv::imwrite(szFilename, roiImg);
cv::imwrite(szOriFilename, image);
} catch (cv::Exception& e)
{
const char* err_msg = e.what();
std::cout << "exception caught: " << err_msg << std::endl;
}
}
#endif
#if !TESTROI
//printf("findContours image\n");
cv::findContours(roiImg, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, cv::Point(0,0));
int nMaxAreaContourIndex = -1;
float fMaxArea = 0.f;
for (size_t s = 0; s < contours.size(); s++)
{
float fArea = cv::contourArea(contours[s]);
if (fArea > fMaxArea)
{
nMaxAreaContourIndex = s;
fMaxArea = fArea;
}
}
{
if (fMaxArea > MAXAREATHRESHOLD && nMaxAreaContourIndex >= 0)
{
cv::Moments mu;
mu = cv::moments(contours[nMaxAreaContourIndex], false);
cv::Point2f center(mu.m10 / mu.m00, mu.m01 / mu.m00); // point in center (x only)
printf("Find a region: Area=%f, center(%f, %f)\n", fMaxArea, center.x, center.y);
nCenterX = (int32_t)center.x;
nCenterY = (int32_t)center.y;
nRet = 1;
// here is the center pixel
#if 0
{
try {
cv::circle(roiImg, center, 5, cv::Scalar(255, 255, 255), -1, 8, 0);
} catch (cv::Exception& e)
{
const char* err_msg = e.what();
std::cout << "exception caught: " << err_msg << std::endl;
}
sprintf(szFilename, "roi_image%d.png", nTick);
sprintf(szOriFilename, "image%d.png", nTick);
try {
cv::drawContours(roiImg, contours, s, cv::Scalar(255, 255, 255), 2, 8, hierarchy, 0, cv::Point());
cv::imwrite(szFilename, roiImg);
//cv::imwrite(szOriFilename, image);
#if PRESERVEROI
sprintf(szOriROIFilename, "ori_roi_image%d.png", nTick);
cv::imwrite(szOriROIFilename, roiImgPreserve);
#endif
} catch (cv::Exception& e)
{
const char* err_msg = e.what();
std::cout << "exception caught: " << err_msg << std::endl;
}
}
#endif
}
}
#endif
}
return nRet;
}