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Rmse value is 66

Open AkhilaPerumalla123 opened this issue 2 years ago • 6 comments

Hi, I captured images using 2 webcams of the same specifications simultaneously. rmse value returned when each camera is calibrated is around 0.11. When they are setreocalibrated, the rmse value returned is around 66.

Is it a good rmse value? if not how to achieve good rmse value?

AkhilaPerumalla123 avatar Aug 24 '22 09:08 AkhilaPerumalla123

Hi @TemugeB, Can you please help me with this?

AkhilaPerumalla123 avatar Sep 06 '22 06:09 AkhilaPerumalla123

Hi,

Sorry for the delay. An rmse of 66 is definitely very bad. Did you make sure the calibration settings file was updated correctly? Also, when doing stereo calibration step, it is very important that you keep your hand steady. Are the calibration patterns large enough in both camera views at the same time? If the calibration pattern is too small, you will run into problems.

TemugeB avatar Sep 06 '22 09:09 TemugeB

I captured steady images. But, for some of the images the the direction is horizontal and for some of the images the direction is vertical.

stereo-f-2 stereo-s-2 stereo-f-6 stereo-s-6

AkhilaPerumalla123 avatar Sep 07 '22 09:09 AkhilaPerumalla123

This is happening because your calibration pattern has equal number of rows and columns. I suggest you print out a calibration pattern that has different number of columns and rows. Or you can simply skip the frames where this is happening. The "O" in images refer to the origin of the calibration points. So the "O"s and the directions should match in both images.

Additionally, your camera is introducing too much radial distortion. To fix this, you need to call openCV's undistort function or find a camera that does not introduce radial distortion. Here is OpenCV's tutorial on how to undistort: link. It is quite simple to use.

TemugeB avatar Sep 07 '22 09:09 TemugeB

Hi @TemugeB,

By taking a calibration pattern with different numbers of rows and columns, I reduced it to 2.88.

Any suggestions to improve it further?

AkhilaPerumalla123 avatar Sep 08 '22 08:09 AkhilaPerumalla123

Hi @TemugeB,

Can you mention the specifications of the camera you used to capture the pictures and videos?

It will be really helpful.

AkhilaPerumalla123 avatar Sep 20 '22 05:09 AkhilaPerumalla123