What are these red borders in the atlas?

[mali-tintash]

So I've been playing with the code. I've made a lot of changes to the code understand some concepts. And I didn't notice until just recently that the atlas being formed has these "Red" borders around the rects.
It's not there in the original code. But since there are a lot of changes in my version, I am unable to trace where this could be coming from.
Any pointers ?

[18892021125]

generate_texture_patches().cpp/generate_candidate(),
byte_image = mve::image::crop(view_image, width, height, min_x, min_y, *math::Vec3uc(255, 0, 255));
(255.0.255)is pink,

[mali-tintash]

generate_texture_patches().cpp/generate_candidate(), byte_image = mve::image::crop(view_image, width, height, min_x, min_y, *math::Vec3uc(255, 0, 255)); (255.0.255)is pink,

But is the border supposed to be visible? I didn't notice it in the atlases generated using original code.