Algorithm 2.

Inference algorithm for the CHM.

Input: An input image X, Θs1, βS, Nstage, L.

Output: υ̂.

• Compute the output of first classifier, υ̂11, using equation (2).

for S =1 to Nstage do

for l = 2 to L do

• Compute output of the 1'th bottom-up classifier, υ̂sl, using equation (2).

end for

• Compute output of the top-down classifier, ζ̂sl, using equation (4).

• υ̂(s+1)1→ζ̂s.

end for

• υ̂ → ζ̂s.