Efficiently set array values to zero if not equal to a certain number? [duplicate]

Question

I'm working in Python reading in images, and getting a 3-dimensional matrix of RGB values for pixels.

I want to take these 3-d arrays and make a matrix with only RGB values equal to r=62, g=57, b=47.

How can I do this? I've looked into masking but I don't understand how to implement this.

Edit: I'm talking about numpy arrays not lists. numpy has a lot of built in functions, for loops are pretty inefficient.

@Art I said arrays. imread from scimage.io returns a 3-d numpy array. — J. Smith
– J. Smith, Commented Dec 12, 2016 at 0:40
@TigerhawkT3 that post is for lists, does it also work for 3-d numpy arrays? — J. Smith
– J. Smith, Commented Dec 12, 2016 at 0:41
That would be stackoverflow.com/questions/19666626/… instead then. Next time, please provide all relevant information within your question. — TigerhawkT3
– TigerhawkT3, Commented Dec 12, 2016 at 0:45

DYZ · Accepted Answer · 2016-12-12 00:41:35Z

1

If rgb is a NumPy array, then this should work:

rgb[rgb!=[62,57,47]]=0

answered Dec 12, 2016 at 0:41

DYZ

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