topic How to convert pixel relative focal lengths to mm for R200 in Items with no label

How to convert pixel relative focal lengths to mm for R200

MHaub1 — Sat, 06 Jan 2018 13:51:16 GMT

Ive been playing around with the Intel Realsense R200 Camera.

I am able to exact focal length in x and y i.e. fx and fy, but only "up to scale relative to pixel width and height, respectively"

At the moment I dont see any way of querying the pixel dimensions in mm from the API nor can I find them in the tech specs.

So my question is: How can I get the fx and fy in mm? One way I can think of is to take a picture of my checkerboard pattern and count the number of pixels and divide by the size in mm.

Is there a better/more elegant way? It seems kind of..imprecise.

Best,

Marc

Re: How to convert pixel relative focal lengths to mm for R200

MHaub1 — Sat, 06 Jan 2018 22:56:16 GMT

For the interested, I got a very good answer on stack exchange.

It was actually an ill posed question, since I assumed that fx and fy were resolution independent.

Since they are not it doesn't make sense to request fx and fy in only millimeters.

https://cs.stackexchange.com/questions/86328/how-to-convert-pixel-relative-focal-lengths-to-mm https://cs.stackexchange.com/questions/86328/how-to-convert-pixel-relative-focal-lengths-to-mm

Best,

Marc

Re: How to convert pixel relative focal lengths to mm for R200

idata — Mon, 08 Jan 2018 22:52:59 GMT

Hello cv_marc_90,

Thank you for your interest on Intel® RealSense™ Technology.

We appreciate that you took the time to share this information with the community.

Please let us know if further assistance is required or if we can close this case.

We will be looking forward for your reply.

Best regards,

Josh B.

Intel Customer Support