With Raspberry Pi's still overpriced, this off the shelf solution for TV ambient lighting was about the same price, with much less setup work : r/homeautomation
5v Ws2812b Usb Led Strip Light Wifi Wled Adalight Hyperion Ambient Kit For Desktop Pc Screen 1m 2m 3m 4m 5m 5050 Rgb Dream Color - Led Strip - AliExpress
Ambient Lighting setup running on a Raspberry Pi 3B+ with Hyperion : r/raspberry_pi
5v Ws2812b Usb Led Strip Light Wifi Wled Adalight Hyperion Ambient Kit For Desktop Pc Screen 1m 2m 3m 4m 5m 5050 Rgb Dream Color - Led Strip - AliExpress
Saw some Hyperion posts so I decided to try it myself. Two hours later I now have Ambilight on my Sony TV! : r/homeassistant