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am looking the kinect calibration and depth calculation.


z = b*f / d

There is "4.1 Focal lengths".

IR focal length is 580 pixels.

Could you please tell me why camera focal length is used in terms of pixels

instead of in mm or in meteres ?

Originally posted by rosmaker on ROS Answers with karma: 51 on 2012-08-06

Post score: 1

Original comments

Comment by rosmaker on 2012-08-06:
Sorry. I know that former question doesn't uploading. It is closed

Comment by piyushk on 2012-08-07:
I'd recommend editing the title to something a bit more relevant (focal length in pixels etc..)


1 Answer 1


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It does not matter whether the focal length is given in pixels or mm, as the relationship is determined by the sensor and image sizes. Go through the following link for more details: http://www.bobatkins.com/photography/technical/measuring_focal_length.html

In general, it is a good idea to have the focal length in pixels as the image size is generally known. Knowing the full intrinsic camera matrix allows for independence from the image size as well.

Originally posted by piyushk with karma: 2871 on 2012-08-07

This answer was ACCEPTED on the original site

Post score: 0


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