groupgets / purethermal1-firmware

Reference firmware for PureThermal 1 FLIR Lepton Dev Kit
MIT License
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raspberry pi 4 - pure thermal 2 - chromium #47

Open rvegele opened 1 year ago

rvegele commented 1 year ago

Hi,

I'm trying to get this module to work with a Raspberry pi 4. Being quite new I was wondering if I should be able to work just through a USB connection or do I need to connect it differently? I'm running Bullseye.

When usb is plugged in I just get a lot of noise from the 'shutter'(?) of the lepton module. Not what I get when using it on my PC. Looking at chrome://device-log the device seems to be connected / disconnected every few seconds apart.

Thanks.

rvegele commented 1 year ago

I've managed to get my hands on the PT2 in order to do a firmware update. I believe I'm getting somewhere. But I'm faced with the following issue:

https://groups.google.com/g/flir-lepton/c/88PrZI1-A8I

Is there a way somewhere in the firmware to adjust the value range I'm receiving as my image is also very "black". With minor gray-ish areas in the hot spots.

From one of the posts "I looked through this really quickly and I didn't see any normalization done in there. When you're dealing with thermal data, you have to contrast-extend the images if you want to see something. On a Lepton 2.5/3.5 your 16-bit values represent temperatures in centikelvin (kelvin 100), so for example, a pixel that is at 29.5C would be a value of 30265, which is right around 0.45 65535, the values you're seeing. The whole scene is going to be around this temperature, so you have to scale these values up so that you have contrast in the range you're interested in seeing. You can do this based on max/min in the scene, or you can set a fixed max and min, and make those values be 0.0 and 1.0, then offset and scale the data into that range."