Find boundary of binary object

I have a binary matrix consisting of a closed irregular shaped object. I want to find the boundary pixels. I tried using:

Bound=bwtraceboundarybwtraceboundary(logical(Bmatrix),[row,col],'S');

where [row,col] is the first non-zero pixel. However, I am running this with many different cases and I cannot manually look for the direction each time. I get the error:

"Error using bwtraceboundarymex The boundary trace failed to terminate correctly. The problem may have been caused by specifying an initial step direction that was inconsistent with the trace direction. Try specifying the trace direction explicitly."

Therefor, is there a better tool than bwtraceboundary in finding the object boundaries for cases like these?

[Ridwan Alam]

can you share your Bmatrix and [row,col] for us to try to debug?