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2014-10-31 10:29:22 -0500 received badge  Editor (source)
2014-10-31 10:27:11 -0500 commented question how to calibrate camera (stereo)

No problem, in fact thank you for your efforts. The two cameras are fixed on the microscope (with screw). So I am pretty sure their position doesn't change and I don't process the images after the acqusition. Yea, hopefully someone knows what is wrong with my images.

Thanks again :D

2014-10-31 05:32:23 -0500 commented question how to calibrate camera (stereo)

the calibration target is a circle grid.

the calibration images is here https://dl.dropboxusercontent.com/u/15437492/images.zip

I have to mask these images appropiately in order to find the circles.

images with markers: https://dl.dropboxusercontent.com/u/15437492/marked_images.zip

markers data (points only; format is objectX,objectY,objectZ,img1X,img1Y,img2X,img2Y per line) https://dl.dropboxusercontent.com/u/15437492/markers.zip

if you want you can load these points as the input for stereocalib. My program is very similar to the one from opencv example.

I tried both First: to calibrate the camera individually before stereo-calibration (ofc fix-intrinsic flag is set while using stereocalib) Second: directly use stereocalib I still have black images as output.

2014-10-30 13:35:31 -0500 commented question how to calibrate camera (stereo)

hi thanks for your answer, i am gonna post them tomorrow.

2014-10-30 13:12:09 -0500 asked a question how to calibrate camera (stereo)

Hi i am trying to calibrate two cameras which are looking at a mini object through a microscope. The calibration target is a circle grid.

I have to mark these images appropriately in order to find the circles (images with markers)

markers data : (points only; format is objectX,objectY,objectZ,img1X,img1Y,img2X,img2Y per line) if you want you can load these points as the input for stereocalib.

My program is very similar to the one from opencv example. I tried both :

  • First: to calibrate the camera individually before stereo-calibration (ofc fix-intrinsic flag is set while using stereocalib)
  • Second: directly use stereocalib

I still have black images as rectification output.

From what I read the calibration should be done by moving the calibration target around, so that it fulfill some criteria:

  1. size (by moving the target approaching the camera and away from the camera)
  2. area (by moving along the x axis and y axis direction)
  3. skew (by tilting the target with various angle)

But due to space and lighting limitation I can only move up and down using the calibration target. It is impossible to do the (stereo) calibration like this? Since I got only black images after using stereo rectify.

Thank you

2013-08-26 07:21:49 -0500 received badge  Scholar (source)
2013-08-13 03:44:15 -0500 asked a question stereo rectify incorrect result

Hi i am new to computer vision and also to opencv.

I am trying to rectify a stereo images with the following workflow:

  1. Calibrate left and right camera with "calibrateCamera" on both images.
  2. "stereoCalibrate" using the camera matrix and distortion coeff found in the previous step as the input (fix intrinsic flag)
  3. "stereoRectify" using the camera matrix, distortion coeff, rotation- and translation-matrix from the previous step.
  4. "initUndistortRectifyMap" using the output from previous steps
  5. "remap" using the output from previous step

After remap I got a weird result, the images are not rectified at all. These are the images I used:

  1. img1.PNG
  2. img2.PNG

These are the result:

  1. result1.png
  2. result2.png

I think I made a basic mistake but I don't know what. Could anyone clarify me?

Thank you in advance!