background subtraction FPGA

[mesolmaz]

I am using NI-1473R for image processing applications. Specifically, I use the 10-tap 8-bit Camera with DRAM example and build on it. My project requires me to do background subtraction. I am able to send an image from the HardDrive to the FPGA through FIFO. But I am not able to store the image in DRAM since it is already being used in the Vi. In this Vi, DRAM is used as a FIFO to hold intermediate image data from the camera between the packers (e.g. 80 to 256). There is no addressing as the CLIP interface just stores data on the banks of DRAM. 

I am thinking of changing the DRAM from FIFO to Random Access to store my image, and perhaps hold the camera data in Bank0 and background image in the Bank1. How can I go about this? Will this cause a problem with write/read operations?

Also, Is there any example of DRAM storage NI-1473R? I was only able to find examples for PXI series FPGA.

many thanks,

Mehmet

[Dane.S]

Mehmet,

Here is some information on writing to the DRAM:

http://www.ni.com/white-paper/14571/en/

Why are you trying to write this image to DRAM?

Could you write a copy of your image to DRAM?

[mesolmaz]

Hi Dane,

I need to store this image in the DRAM as long as I run the FPGA. This image is the 'dark' image with 0 exposure and will be sent from the PC. I want to do image subtraction in real time to remove the CMOS camera noise. 

As it currently stands, the DRAM is a FIFO and can not be used as in the white paper. 

[AmitShachaf]

Hi 

It will be very difficult to read the Image from DRAM in full speed of 8Bit x 10 Taps.

Is the camera you are using the Basler acE2000-340K. 

I am working with this camera. I think that to correct this camera vector will be sufficient.

Then you don't need to use the DRAM and you can use a block of memory.

That is what I am going to do.

[mesolmaz]

Hi Amit,

Based on my calculations, I cannot use the BRAM for the full frame (2MB). Yes, I use the same camera.

Here is where I am stuck so far. I am trying to write and read from DRAM which is used as socketed CLIP. My Vi is attached. I used a similar routine available at this link (https://forums.ni.com/t5/Example-Program-Drafts/NI-FlexRIO-Basic-DRAM-Example/ta-p/3500004). 

[mesolmaz]

I am attaching the code I am working on so far. I am trying to write an image from the camera to DRAM. I couldn't find an example that uses CLIP as random access memory. I am controlling the write/read operation based on the Details part of DRAM banks. 

As soon as I press Go?, I should store a frame in DRAM and start reading as soon as writing is finished. So far, I am only seeing a black image, which tells me I am not able to write into DRAM.