CODEWITHSUNDEEP
imagematlabimage-processing
hs100
hs100

Reputation: 496

Matlab: How can I find the number of black pixels in a color image?

I wish to find the number of black pixels in a color image using MATLAB, how can I do it?

Thanks.

Upvotes: 3

Views: 1049

Answers (1)

Divakar
Divakar

Reputation: 221514

Use nnz like this -

nnz(all(im==0,3))

where im is your image data.

Alternatives - sum(reshape(all(im==0,3),[],1)) and sum(sum(all(im==0,3))).

The assumption here is that black pixels are triplets (0,0,0).

Instead if you define black pixels as pixels that have values in the interval [0 th] for the same pixel location across all channels, use this -

nnz(all(im<=th,3))

Upvotes: 7

Related Questions