Hello!
Context: I am re-implementing the kmeans algorithm into a kmajority algorithm for binary descriptors, like ORB, based on hamming distances, inspired by this paper. This requires, for every binary descriptor in a cluster, to make each bit position of each descriptor "vote" for either 0 or 1 for the final value of that position in the cluster center.
Descriptor 1: 0 0 0 0 1 0 1 0 ...
Descriptor 2: 1 0 1 0 1 0 1 0 ...
Descriptor 3: 1 0 0 0 1 0 0 0 ...
---------------------------------
Center : 1 0 0 0 1 0 1 0 ... <-- after majority vote for each bit
Question: ORB descriptors are stored in their mats as uchar, not bits. They are stored in a Mat of N rows (1 row per descriptor) and 32 columns (32 uchar for 256 bits). Obviously, I'm not interested in uchars, it's the bits I want. Therefore, is requesting the rows with:
bool* descriptor = myMat .ptr<bool>(rowIndex)
... the right approach if I want to iterate over a descriptor bit by bit instead of uchar by uchar? (I'm pretty unfamiliar with C++).