libflac++-dev - 1.3.2-3+deb10u2 main

FLAC stands for Free Lossless Audio Codec. Grossly oversimplified, FLAC is
similar to MP3, but lossless. The FLAC project consists of:
.
* The stream format
* libFLAC, which implements a reference encoder, stream decoder, and file
decoder
* flac, which is a command-line wrapper around libFLAC to encode and decode
.flac files
* Input plugins for various music players (Winamp, XMMS, and more in the
works)
.
This package contains the development library libFLAC++.