synchronize IMU data, color and depth datastreams

[bowieshi]

Hi. Can I ask whether the SDK has support for synchronizing IMU data with color and depth datastreams. I see that IMU has very high data frame rate but color and depth have at most 30 fps. How can I synchronize them so that I have each frame camera extrinsic relative to the starting point. Thank you.

[bowieshi]

I am currently using ROS to soft synchronize IMU data, color and depth. And I find that the system timestamp of color and depth image in the same frameSet does not exactly same.

auto frameSet = pipeline.waitForFrames(1000);
if(frameSet == nullptr) {
    std::cout << "The frameset is null!" << std::endl;
    continue;
}
frameCount++;

auto colorFrame = frameSet->colorFrame();
auto depthFrame = frameSet->depthFrame();

like the following, the depth image and color image will have about 10ms system timestamp gap. Can I inquire is this a normal phenomenon?

Also, when I read the IMU data. I find when my Orbbec camera is static without motion. The measured Accel is not zero. The accel of z axis is near gravity acceleration. But I don't know why accel in y axis is not zero. Is there any instruction on this. Thank you very much!

[bowieshi]

@zhonghong322