April Tag support for larger frame sizes

I am experimenting with some April Tag detection on the RT1062. I am only able to detect April Tags when setting the frame size to QVGA or smaller. Even at QVGA size, the frame rate drops to about 5 FPS. Is this performance expected and is there anything I could do to support VGA size? I am detecting tags from about 15 feet away which means I need pretty large tags (8 inches) to recognize them.

Hi, can you install the latest development firmware (Tools->Install Development Release)? I merged a fix for AprilTags which dealt with it having a max resolution issue. This should clear your problem up. It should work at VGA then.

As for frame rate… there’s not much I can do there. AprilTags is an extremely demanding algorithm. It even brings desktop CPUs to their knees. You should get about 3-4 FPS at 320x240.

We may be able to speed this up once we merge in an updated camera driver for the RT1062. However, I don’t think we’ll be able to get much beyond 6-8 FPS.

VGA will definitely be at the 1FPS level at max even after we upgrade the camera driver. I see right now it’s at 0.5 FPS. This is about half off from the H7 Plus. However, as mentioned, the RT1062 camera driver is not full DMA accelerated so some of the CPU time is spent moving pixels to the image buffer. We hope to have this fixed and optimized in the following months as the product matures.

i wish apritag could have 2-3 FPS at FHD by openmv.
Come on,you can!

After installing the development firmware, I am seeing the following error at VGA resolution: “MemoryError: Out of fast frame buffer stack memory”.

Not surprising but this is the line it is throwing an error on.

for tag in img.find_apriltags(families=image.TAG16H5):

After some more troubleshooting, it looks like I am able to run the sample file at VGA size. In my project file, I am creating two additional frame buffers; one for frame differencing; the other so I can maintain the original image for display on LCD. That seems to put me over the memory limitations - any thoughts on how I can overcome this limitation in my application?

Use the RT1062 firmware here: Unexpected import problem RT1062 and SD card - #6 by kwagyeman

I unlocked a huge amount of frame buffer RAM that was not being used.

Sorry, it looks like the settings for the IMX devboard we used to bringup the software had not been updated to reflect the increased amount of capabilities of the RT1062 camera.