Which are the units of a disparity value?

Question

I need some help with disparity maps.

I was wondering which are the exact units of a disparity value? Is it pixel units or mm?

Every answer would be appreciated

I obtained the disparity map of a pair of imagen by using Stereo BM algorithm. Now I want to obtain the depth value. Thats the reason why I need to know the units — Tony, Oct 09 '19 at 10:11

score 3 · Answer 1 · answered Oct 09 '19 at 13:13

3

The disparity is in pixels. And the relation to depth, baseline and focal length is:

disparity [pixels]       focal length [pixels]
------------------   =   ---------------------
  baseline [mm]                depth [mm]

answered Oct 09 '19 at 13:13

Pibben

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score 0 · Answer 2 · answered Dec 29 '19 at 08:47

@Pibben just nailed the answer. But I would like to add that the units of baseline basically come from the calibration. If the checkerboard size is given in mm, baseline would be in mm, if its given in other units such as cm,meters, the depth is also calculated in the latter units.

Which are the units of a disparity value?

2 Answers2