hierchical box AddrGen issue

  • Hello,

    I'm a new forum user and a beginner in using visual applets. I take this opportunity to greet everyone.

    I am interested in using the sample algorithms for HDR (gray level) found in the installation path:


    \examples\Processing\HighDynamicRange\HDR_CRC_Gray.va

    \examples\Processing\HighDynamicRange\HDR_linearW_Gray_3_Base.va


    I think I have problem setting up the "AddrGen" box inside the "Image Sequence" box. I'm working with 2 gray level images 4096 * 500 (WxH). Can anyone help me about it? thank you so much for your availability

  • Hello Grubbier,


    I did a quick modification of the design to a sequence length of two and an image size of 4096x500. The results seem a little bright to me so I adjusted the alpha value as explained in the documentation. (shift = 21).


    Use the simulation to get your results.


    Johannes

  • Dear Johannes,


    Normally there is a timebase related to each HDR image in the sequence.

    (shift = 21)

    Adopting the real used time base would have the same effect.


    pasted-from-clipboard.png


    Calculation is mentioned in the comments (within screenshot above) and can be changed in Image1/Image2 H-Box in Const:

    pasted-from-clipboard.png


    Best regards

  • First of all I would like to thank for the answer obtained.

    I tested "HDR_CRC_Gray_Seq2_4096x500.va" in simulation mode with two test images and it works.

    I am currently in possession of a microEnable IV VD1-CL tested together with a Teledyne DALSA P4 4K Mono camera:


    - TestPattern "Ramp"

    - Base Camera Link Mode

    - MultiLine Exposure Mode that generates a 8192*500 frame (this frame is read by the FrameBufferRandomizer to generate a 4096 * 1000 frame for the algorithm to work)


    The file "HDR_CRC_Gray_Seq2_4096x500.va" does not seem to compile on VD1-CL presumably due to excess of RAM resources required.



    So I tried to tune the "Exposure Fusion.va" example to my needs:

    (Base Camera Gray level image: 4096 * 500 output image; I attach it).

    The compilation on VD1-CL is successful but the acquisition frequency does not go above about 1.5Khz.


    I wanted to know if these HDR algorithms involve a frequency limitation.

    Also, if it were possible, I would like to know if a version in FULL Camera link mode can be implemented (involves the insertion of buffers that consume resources)


    Did I make any mistakes?

    Thanks a lot for the answer

  • Dear Grubbier,


    Thank you for the positive response.

    The compilation on VD1-CL is successful but the acquisition frequency does not go above about 1.5Khz.

    I wanted to know if these HDR algorithms involve a frequency limitation.

    Also, if it were possible, I would like to know if a version in FULL Camera link mode can be implemented


    The mE4-VD1-CL is due to its "age" pretty limited in its ressources.

    Especially the DMA transfer can handle only up to 200 MB/s while the amount of memory operators is limited to only 2 of 128 MB each!


    In case the overall output bandwidth and especially the memory bandwidth is within the spec of mE4-VD1-CL you can go for CL FULL (or do you mean DECA). But I really doubt that the memory bandwidth requirements of the HDR approach is getting well served by the *VD1*.


    All later and especially more current platforms (recommending mE5-MA-VCL) have much more ressources:

    4 x memory, higher DMA rates...


    Best regards

  • Dear Grubbier,


    I looked into your design:

    does not go above about 1.5Khz

    (1.5 kHz) * 4096 * (8 bit) = 6.14400 MB / s

    I would expect a higher bandwidth for your design...


    Your design is using parallelism = 1 around the memory operators.

    That will limit the bandwidth there to 62.5 MPixel/s.

    You are using 2 memories for the same operation.

    That can be combined to 1 memory.
    Or you combine both in parallel to double the bandwidth.


    Best regards

  • I agree in using the new 5 VCL marathon, my company is purchasing.

    In the meantime, to test this HDR feature of our interest, I have the old microenable IV as platform.


    I try to optimize the part of the two framebuffer randomizers in one


    Best Regards