This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
PianoKeysWithOctavesNumbered. en bitmap image of piano with the octave numbered from to and with middle and highlighted Own Cyndaquazy Octaves Musical keyboard diagrams
Page 2023 Free-images.com. All images are Public Domain