# Calculating Kinect pixel size

• ### Question

• Hi,

I have a Kinect. I have no problems running it and getting (also) depth info.

I am looking for suggestions on how to calculate each pixel size as a function of the vertical distance (i.e. the depth information the Kinect generates) from the sensor

Thanks

Yori

Wednesday, March 7, 2012 3:33 AM

• The horizontal angle of view for the depth camera is 57 degrees.

Where d is depth and w is the frame width, you should be able to calculate a pixel width as: tan(28.5) * 2 * d/w.

[Shameless plug -- this formula is from chapter 3 of the Beginning Kinect Programming book.]

You can also retrieve the horizontal field of view of the depth camera (57 degrees) by calling DepthImageStream.NominalHorizontalFieldOfView property.

James Ashley - Presentation Layer Architect at Razorfish Emerging Experiences
jamesashley@imaginativeuniversal.com
www.imaginativeuniversal.com www.emergingexperiences.com

Thursday, March 8, 2012 10:20 PM

### All replies

• The horizontal angle of view for the depth camera is 57 degrees.

Where d is depth and w is the frame width, you should be able to calculate a pixel width as: tan(28.5) * 2 * d/w.

[Shameless plug -- this formula is from chapter 3 of the Beginning Kinect Programming book.]

You can also retrieve the horizontal field of view of the depth camera (57 degrees) by calling DepthImageStream.NominalHorizontalFieldOfView property.

James Ashley - Presentation Layer Architect at Razorfish Emerging Experiences
jamesashley@imaginativeuniversal.com
www.imaginativeuniversal.com www.emergingexperiences.com

Thursday, March 8, 2012 10:20 PM
• Note though that DepthImageStream.NominalHorizontalFieldOfView is 58,5 and not 57 as specified in the documentation. Likewise is DepthImageStream.NominalVerticalFieldOfView 45,6 and not 43. (and the values change if you change the resolution - for some unknown reason)

Best regards,

Jesper

Tuesday, April 17, 2012 1:13 PM