Turning an ESP32 into a Thermal USB Webcam Last time I faked a webcam on an ESP32; this time I built a real one. The ESP32-S3âs native USB + UVC with MJPEG makes a normal camera dead simpleâgrab JPEG frames and stream. The fun bit is turning an MLX90640 (32Ă24 thermal) into a proper USB camera: read over I2C, color-map, scale up to 320Ă240 (nearest or bilinear), JPEG encode, and streamâworks in any camera app, no drivers. Bonus lesson: if an I2C scan finds nothing, stop blaming software; mine was a bad 3.3 V regulator solder joint. 15 February 2026
When âSoftware Bugsâ Are Actually Bad Soldering A quick MLX90640 IR camera test turned into a dead-on-I2C mystery. I ran the usual checksâaddresses, pull-ups, voltages, wiringâand even fixed my forgotten UART/I2C jumper, but still nothing. A peek under the microscope revealed sketchy solder on the 3V3 LDO; a quick reflow and the sensor sprang to life. Lesson relearned: donât trust factory soldering, look early with a microscope, and stop blaming software when the hardwareâs silent. 25 January 2026