An audio to MIDI - Converter Design
This design in VHDL for PLDs and FPGAs
converts one channel of audio data in real time into
MIDI-like tone information using
protocole to fit well into the Audio-DSP-Workstation.
By analyzing the incoming audio stream
with a small DFT-like algorithm, the dominating frequency is detected
by ignoring harmonics. The corresponding MIDI tone number is discovered
using a frequency table. Deviation of the given note's frequency
is detected too and transmitted as a vibrato controller code. Also
some others MIDI-CTRL commands are derived from the audio
This design is based on an idea, formerly realized for DSP-Systems
in C-language and had been changed to VHDL for a modern Spartan
See the former
article for more details.