Draw a marker: problems with PTS parameter

Hi,

I've a matrix/image 256x256 of binaries and a set of points as matrix indices [m n]

[m n] = 

        45    98
        23   118
        45   185

I want to draw markers in these points. I tried with Computer Vision toolbox by:

markerInserter = vision.MarkerInserter

J = step(markerInserter,bw,[m n])

But it returns an error:

Error using MarkerInserter/step
The Pts input data type must be integer.

I don't understand it. Coordinates are integers.

Answer 1

[Anand]

The coordinates may be integer valued, but are not stored in an integer datatype. You can see this if you do the following:

>> class(m)

I'd expect you to see double as the result. In order to use the MarkerInserter, points are expected to be of an integer datatype, namely one of the following: uint8, uint16, uint32, uint64, int8, int16, int32 or int64.

So, you can convert the matrix indices to an integer type:

J = step(markerInserter,bw,uint32([m n]));

Hope this helps!