Face Detection

Face detection has a wide range of application, we will learn how to do face detection in this tutorial.

Detecting Faces

Loading Extensions

Search "KOI" in the search bar.

Or copy and paste the following link to the search bar.

https://github.com/KittenBot/pxt-koi

Blocks for face detection:

Sample Program:

Program Flow

Download the program to the Micro:bit, the pixel on the Micro:bit move accordingly.

Mapping coordinates

We can use the map function to map a value to a new range.

Sample Code

Face Detection (Extension0.5.7)

Extension Version and Updates

There may be updates to extensions periodically, please refer to the following link to update/downgrade your extension.

Makecode Extension Update

FAQ

1: There is no reaction after pressing the buttons on the Micro:bit.

· A: This is because KOI has a longer boot time than Micro:bit. When the power is turned on, Micro:bit has already ran the code for KOI initialization before KOI is ready.

· Solution: Reset your Micro:bit after KOI has been turned on. (The trick is to let KOI power on completely before initialization.)

2: Does KOI work with 3V input?

· A: No, KOI only works with 5V.