LightBridge 2 VCL - Acquisition - 4X-1Y Camera, 16-bit Pixels - Camera Link Full

  • Hello,


    I am trying to help someone use a Quad Tap, 16-bit Camera Link Full camera with Visual Applets. Right now, we are trying to work out how to accomplish acquiring images before moving on to image processing. The camera has a resolution of 256 x 257, and the tap geometry is 4X-1Y. I did not see this as one of the possible options in the Full Gray Camera operator, but I have an idea on how to get around this.


    To emulate a 4X-1Y Quad Tap 16-bit camera, we could use the FullGreyCamera operator. The bit assignment of 16-Bit Mono Full 4 Taps looks similar to 8-Bit Mono Full 8 taps. In 8-Bit Mono Full 8 taps mode, a 16-bit pixel would be interpreted as 2 8-Bit pixels. Thus, the pixel at (0,0) would be the least significant byte of the pixel, and the pixel at (1,0) would be the most significant byte. The pixel at (1,0) would have the incorrect endianness, so it would need to be “flipped.” Then, the two pixels could be combined into a single 16-bit pixel. 8-Bit Mono Full 8 taps mode also has a ninth 8-bit pixel which does not exist in 16-Bit Mono Full 4 Taps mode, so this must be sent to the trash. This means that Visual Applets will see an image width of 256 * 2 * (9/8) = 576 pixels.


    From there, we could adapt the TapSorting_8X_1Y.va example to 4-taps. We would need to take out the parameter translations since we do not have Visual Applets Expert.


    Does this sound feasible? We do not have access to the camera yet, so we cannot actually test it out right now.


    Thanks,

    Michael

  • Hi Michael


    you wrote

    Thus, the pixel at (0,0) would be the least significant byte of the pixel, and the pixel at (1,0) would be the most significant byte. The pixel at (1,0) would have the incorrect endianness, so it would need to be “flipped.”

    Hm. I can't see that it is flipped from you CL Spec image.

    8-Bit Mono Full 8 taps mode also has a ninth 8-bit pixel which does not exist in 16-Bit Mono Full 4 Taps mode, so this must be sent to the trash.

    If you set the VisualApplets operator to 8 Tap it will not use the nineth pixel.


    I think the solution is very simple:


    • Use FullGrayCamera operator set to 8 Tap static with a Max. Image Width on its output link doubled compared to the cam width.
    • Use operator CastParallel to get 16Bit
    • Use an adaptation of the Tap Sorting examples to sort the four taps.

    I've added a VA sample. It is a little simpler compared to the examples in the VA installation directory but does the same with a little more FPGA ressources.


    Johannes

    Files


    Johannes Trein
    Group Leader R&D
    frame grabber

    Basler AG



  • Hm. I can't see that it is flipped from you CL Spec image.

    Upon looking at it again, I can see you are correct. I must have been confused.

    If you set the VisualApplets operator to 8 Tap it will not use the nineth pixel.

    I was wondering about that. It seems odd that there would be more pixels than taps.

    I've added a VA sample. It is a little simpler compared to the examples in the VA installation directory but does the same with a little more FPGA ressources.

    Thank you very much, this will be very helpful! I really appreciate the help:)