lvgl_cpp/demos/music/README.md

Music player demo

Overview

The music player demo shows what kind of modern, smartphone-like user interfaces can be created on LVGL. It works the best with display with 480x272 or 272x480 resolution.

Run the demo

• In lv_conf.h or equivalent places set LV_USE_DEMO_MUSIC 1
• With LV_DEMO_MUSIC_AUTO_PLAY enabled a ~60 sec demo will be played.
• After lv_init() and initializing the drivers call lv_demo_music()

How the spectrum animation works

• assets/spectrum.py creates an array of spectrum values from a music. 4 band are created with 33 samples/sec: bass, bass-mid, mid, mid-treble.
• The spectrum meter UI does the followings:
  • Zoom the album cover proportionality to the current bass value
  • Display the 4 bands on the left side of a circle by default at 0°, 45°, 90°, 135°
  • Add extra bars next to the "main bars" with a cosine shape. Add more bars for the lower bands.
  • If there is a large enough bass, add a random offset to the position of the bars. E.g. start from 63° instead of 0°. (bars greater than 180° start again from 0°)
  • If there is no bass, add 1 to the offset of the bars (it creates a "walking" effect)
  • Mirror the bars to the right side of the circle

Using spectrum.py

• install librosa with pip3 install librosa
• run python sectrum.py my_file.mp3
• see the result in spectrum.h