Does the D435 camera need calibration? Distance of visual recognition items within 5 meters

[chaojizhangdaxin]

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Required Info
Camera Model	D400
Firmware Version	(Open RealSense Viewer --> Click info)
Operating System & Version	Linux (Ubuntu16/
Kernel Version (Linux Only)	(e.g. 4.14.13)
Platform	PC
SDK Version	2.16.1
Language	opencv/python }
Segment	Robo

Issue Description

Do you need camera coordinates after aligning depth photographs with RGB photographs?

[dorodnic]

Hi @chaojizhangdaxin Could you please provide more information on the issue? I'm not sure I fully understand.

• D400 would not be a very good solution at 5 meters.
• Depth and Color cameras are calibrated and the SDK offers align class to align images.
• There are also APIs to get the relative transforms between the two infrared sensors and the RGB camera (see camera extrinsics)

[chaojizhangdaxin]

@dorodnic Thank you for your answer. I want to know whether the pixels of RGB and depth images correspond to each other point to point. For example, I want to know the depth value of (x, y) in RGB photos. Is that the depth value of (x, y) in depth images?

[HippoEug]

No, it will not correspond. You will have to align the depth and color frames/images.

Please see rs-align.cpp, there is a class that looks like this rs2::align align(align_to)

[RealSense-Customer-Engineering]

[Realsense Customer Engineering Team Comment] Hi chaojizhangdaxin,

As dorodnic and HippoEug clarified & suggested, please refer to align sample.

Thank you!

[RealSense-Customer-Engineering]

[Realsense Customer Engineering Team Comment] Hi chaojizhangdaxin,

Wonder if you get any updates and still need help? If no, this one will be closed soon.

Thanks!