Hi.
I am a beginner with this computer vision thing.
I have been using examples and openCV tutorials as I am trying to make a program to get depth from stereo.
Now I have a problem: Focal length. I am using a nikon DSLR and after googling I have had this answer which I also found from this forum that the focal length should be in "focal pixels" when using openCV. Also the coordinates and disparity should be in pixels.
I tried the calculations on paper also, by measuring it manually and doing calculations in millimeters. I had all of the units in millimeters. I printed the pictures.
I can't figure out why I don't get the right depth when doing this manually in millimeters.
Can it be the problem that I am using a nikon DSLR, instead of a camera made for computer vision systems? I don't think that this is an actual problem to make a depth map, but because of the purpose it is made, I can't find the right units to make calculations?
The equation goes: Depth = focal length * stereo baseline / disparity, as I may have understood right...
I'd like to have an explanation for the units and the camera, with a source. Also, If you find my question confusing or I am missing something really important knowledge, you could also note for that.