I convert a color image into binary with this line of code


where minThresis 0 and maxThres 1

The output is a black image

My question is since the resulting image is pure black.
Can it still be considered binary? (I just want to make sure)

The reason why I'm asking is because I need a binary image with pixel values of 0's and 1's and since the resulting image (which is a black image) already has the values that I want (i checked the values).

I guess I just want to verify if having a binary image with pixel values of 1's and 0's will always result in a black image

So: from the grayscale image, every pixel that has a value of zero appears with a value of zero in the dst image. Every pixel in the grayscale image whose value is not zero appears with a value of 1 in the dst image.
Huh? Since you have observed that it has pixel values of 0 and 1, it is not a black image; it is a binary image with two different values of pixels: 0 and 1. (See Footnote.)

That makes no sense at all (to me).
It is not a black image; it is a binary image with two different values of pixels: 0 and 1. (But I said that already).

Now on a scale from 0 through 255, a single pixel with a value of 1 (very, very, very dark gray) may be practically indistinguishable from a single pixel with a value of 0 (pure black), or, maybe not.

Whether there is a humanly perceptible difference between your dst image and a pure black image depends on the quality of the monitor (or printer) and room lighting and the visual acuity of the human observer and whether there are large areas of pure black in the middle of large areas of very, very, very dark gray (or vice-versa).

Bottom line: If you are processing the image mathematically, there may be a lot of practical difference between a black image and a binary image with pixel values 0 and 1 (depending on the nature of the mathematical treatment). On the other hand, if you are just looking at the image, well, maybe not so much...




Regards,

Dave

Footnote:
If it just happened that there were no pixels in the grayscale image whose value was zero, then all pixels in the dst image would have had values of 1. It wouldn't be a black picture; it would be a solid very, very, very dark gray picture.

If it just happened that all pixels in the in the grayscale had values equal to zero, then all pixels in the dst image would have had values of zero. Then the dst image would be a solid black picture.

__________________
Sometimes I just can't help myself...

when I said the output is a black image I'm just saying base from what I saw "black image" but mathematically speaking it is a binary image with 1's and 0's

Thanks again for your comments