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IR stream data type

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V Srikrishnan

Hi,

from documentation, i saw that the IR stream data type is of 8bit, Y8. However, i got a recorded bag file where the IR data type is RGB8. I was expecting "uint8" type of data. Is it something to do with the recording settings that Y8 stream is stored as RGB8? what is the colourisation applied?

I also saw that there is a "Color Stream from Depth Imager". which is UYVY(16bit).

unfortunately, i do not have a camera with me nor can access any. 

Any help welcomed!

Thanks

Krishnan

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3 comments

Date Votes
  • MartyG
    • Edited

    On the 400 Series cameras, the IR imager can also provide a color stream in addition to the dedicated color one provided by an RGB imager.  In fact on the D415 model, the RGB and IR imagers use the same Omnivision 2740 component.

    The D415 model can provide color from the left IR imager only.  The D435 models can provide a color stream from both the left and right IR imagers, but they are both monochrome.

    The IR imagers can actually provide both 8-bit (Y8) and 16-bit (Y16) streams.  The Y16 mode is the only stream type that is unrectified, and it is intended for use for camera calibration rather than everyday general use.  So Y16 only works with a small number of resolution / FPS combinations, up to a maximum FPS speed of 25.

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  • V Srikrishnan

    Hi MartyG,

    thanks for the super fast respnse. I have the data from a D415. The data stream i have has been recorded at 1280x720 at 30fps. I have read the IR data streams using python API. the shape of each IR frame is [1280,720,3]. i was expecting [1280,720,]. In the realsense viewer, i see the data dtype as RGB8.

    1. So my question is, assuming normal operation(not calibration), the IR data stream would be Y8, but the data type is of 3 channels than single channel as i i expected. Why is it so? Please note that I am talking of IR stream and not colour stream.What am i missing? Sorry, but i cant get my head around this.

    2.Also, regarding the Y16 stream, from the datasheet i find; it seems to support quite a variety

    Thanks!

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  • MartyG
    • Edited

    UYVY is not the same as Y16.  The image below shows the range of IR formats that are selectable in the RealSense Viewer. 

     

     

    Documentation of the configuration of each RealSense stream format is here:

    http://docs.ros.org/kinetic/api/librealsense/html/namespacers.html#a447cba2f10f1dc5aac305658756c238b 

     

    I ran some tests to see which resolution and FPS combinations were now supported in the Viewer for Y16.

    960x450 @ 15 AND 25 FPS

    1920x1080 @ 15 AND 25 FPS

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