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Where's the best place to store a second frame?

Pixy Software
#1

Any thoughts on the best strategy for storing two complete 320x200 frames (64kB)?

My current thought is to remove as much code as possible to try to make room in SRAM0…

Thanks!

#2

Hi Robb,

That might work. What kind of functionality do you need to keep? You could try storing it in flash since there is 1MB available.

Scott

#3

Thanks for the suggestion!

I want to match features from frame to frame for optical flow. If I can’t store the complete image, I will try to make room for a few relevant patches, or learn how to use the flash…

I decided to try to go with IAR instead of Keil because they have better support for some of the other chips I am interested in (primarily from TI) so I’m still trying to get back to baseline functionality at the moment. (My one week trial of Keil ran out, so hopefully the IAR port won’t take too long.)

#4

Robb, I’m also interested in doing something related to optical flow. If you make any progress, can you post an update? I haven’t been able to get anything to compile using LPCXpresso.

#5

I would suggest downloading a demo version of the Keil tools and working with that until the gcc version is released in December – it was pretty straightforward to modify the code and get it to run.

I got FAST corner detection running without too much trouble… the next step would have been to switch modes between finding a corner regions and tracking flow near those points. It might be necessary to delete some of the unused program code to get everything to fit. There isn’t enough RAM to do flow on the full frames so I really think some intelligent keypoint selection is needed. You should take a look at the PX4flow project code as an example – my plan was to implement something very similar.

I got distracted trying to port to IAR and then I broke my board trying to get the JTAG connector soldered on to figure out why everything compiles but fails to upload. (I am terrible at rework!)

I’ve more or less decided that I want to have more processing power than the M4 can offer anyway… currently working on layout for a low cost Cortex-A9 board with more memory.

Best,

Robb