topic Depth Map of black pixels are not scanned using SR300 in Items with no label

Depth Map of black pixels are not scanned using SR300

SAgga1 — Thu, 29 Nov 2018 15:49:56 GMT

I am using Realsense SR300 Camera for object mapping.

when i scan a object or human, black pixels are not scanned for depth map, so they appear to be hollow.

Something like below. (Hairs, beard appears hollow)

HW Detail : Detail. : Odroid XU4 with Intel Realsense SR300

Is it expected behavior of SR300 ? Seems very strange to me.

Re: Depth Map of black pixels are not scanned using SR300

MartyG — Thu, 29 Nov 2018 23:18:16 GMT

It is due to a physics principle with depth cameras in general, not specifically RealSense. Black or grey colors absorb the laser light, like how black t-shirts soak up sunlight. The camera therefore cannot detect these colors. The principle can also be seen when scanning black cables - there is a cable-shaped black area on the image.

Dark objects can be made more visible to the camera with a fine spray on powder such as baby powder or foot powder. I appreciate that this is not ideal for beards and hair though!

Re: Depth Map of black pixels are not scanned using SR300

ABogd2 — Wed, 05 Dec 2018 16:14:27 GMT

I cannot say for sure about the true black color, but I did see the same behavior with the gray shades.

Actually I was able to get SR300 to "see" my gray t-shirt by changing initial presets.

Re: Depth Map of black pixels are not scanned using SR300

MartyG — Wed, 05 Dec 2018 16:29:39 GMT

I remember that there was an SR300 user who was scanning a sweatshirt with gray and red stripes on it. Only the red stripes were picked up correctly by the camera. Also, in this case too the black hair and beard were not rendered.

Re: Depth Map of black pixels are not scanned using SR300

ABogd2 — Wed, 05 Dec 2018 16:33:02 GMT

color and depth streams are not aligned: