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Jose Salvador's profile - activity

2018-11-15 09:30:50 -0500 received badge  Popular Question (source)
2013-08-15 10:40:45 -0500 answered a question Algorithm Explanation

Its obvious...
In every program language I think its the same... Rewrite your question if you would say why this its divided by two.

2013-08-14 07:52:55 -0500 received badge  Editor (source)
2013-08-14 06:39:49 -0500 asked a question How calculate and use FOV correctly

Hi all, I'm new with OpenCV and a have a dude with calibrationMatrixValues.
I want to calculate the maximum width and height that captures my WebCam to 50cm. I thought calculate using the FOV, for that I have calibrated the camera with a chessboard, as explained here:
http://docs.opencv.org/doc/tutorials/calib3d/camera_calibration/camera_calibration.html#cameracalibrationopencv
I invoke calibrationMatrixValues by passing the matrix ​​calculated. I don't know if this its correct

FileStorage fs2("out_camera_data.xml", FileStorage::READ);
  Mat cameraMatrix2;
  fs2["Camera_Matrix"] >> cameraMatrix2;
  cv::Size imageSize(640,480);
  double apertureWidth = 1;
  double apertureHeight = 1;
  double fieldOfViewX;
  double fieldOfViewY;
  double focalLength;
  cv::Point2d principalPoint;
  double aspectRatio;
  cv::calibrationMatrixValues(cameraMatrix2, imageSize, apertureWidth, apertureHeight, fieldOfViewX, fieldOfViewY, focalLength, principalPoint, aspectRatio);


Whats the apertureWidth/height mean? Are they correct? When I run this, he tells me fovx = 44.68 and fovy = 34.26.These results would be corrects?
I've been doing various tests and looking in different forums, and I can't understand.
I try to get the values I need with these values and I do know if I'm wrong ( with my trigonometry calculations) or its because I call wrong the function. I should get out more or less about 60 cm of width
Any help you can give me would be appreciated,
Sorry for my bad english.
A greeting.