| AKoff Music
Composer Version 2.0
Buy now ($29)
This software is designed for recognition of polyphonic music from
audio source and its conversion to MIDI score. Now one can compose music without MIDI
keyboard and even without knowlege of notes or how to play musical instruments. It is as
easy as humming a tune into a microphone and Composer will do the rest. Composer will take
into consideration individual performance style tracking note dynamics and pitch bends.
Recognition features: Polyphonic music recognition
from pre-recorded WAVE files or directly from audio input of your sound card in real-time.
Tracking note dynamics and pitch bends. Using different harmonic models to improve
recognition of appropriate instruments. Higher harmonics filtering. Restriction of
recognized pitch range. Manual or automatic noise sensitivity control.
- PCM WAVE files playing.
- Standard MIDI files playing.
- Muting and Soloing MIDI Tracks.
- Changing MIDI track name, instrument, volume and pan.
- MIDI track deleting.
- New MIDI file settings (Tempo and Timebase).
- Sync WAVE and MIDI playback.
How It Works
Composer analyzes a stream of audio signals from
pre-recorded WAVE files or directly from audio input of your sound card in real-time. It
can be sound from microphone, linear input or audio CD.
Composer normally recognizes polyphonic music with one
instrument or voice. This means you won't get the appropriate results if you try to
recognize many instruments playing at the same time especially with drums. Composer
determines note dynamics and frequencies and translates this information into MIDI events.
Composer doesn't automatically recognize the types of sounding instruments. Moreover,
human voice and instruments have various timbres and complicated harmonic components,
therefore recognition accuracy depends on concrete instrument or singing style. Also the
recognition is influenced by quality of WAVE recordings such as background noises and
The complicated mathematical algorithms of DSP (Digital
Signal Processing) require a great amount of calculations and consequently a fast
computer. When recognizing audio input in real-time, Composer only works reliably on
Pentium 150 and higher processors. On weaker machines, the incorrect working or dead halt
of the program may occure, which is removed through pressing Ctrl-Alt-Del keys.
During recognition the recorded notes are automatically
shown on the graphic keyboard. After recognition is stopped, you can play and adjust the
obtained melody. You can select the playback MIDI instrument, change octave and also try
to correct music scale or use Pitch Bend Control. Further you can add the recorded track
to the general list of MIDI tracks and then save the generated MIDI file. The last feature
is accessible only in the registered version.
If some notes are recognized incorrectly, you can open
the saved file in any MIDI editor and manually correct your score. If you have MIDI
keyboard, it will be easier to play with keyboard entering results into MIDI editor. But
if you aren't a musician, Composer will help you to record your own melody in a popular
MIDI format using only your voice or your non-MIDI instrument.
Wave to Midi Samples
You can download and listen to source wave-files and
recognized midi-results. Wave recording format is PCM 11025 Hz, 8-bits, mono.
guitar.wav (43117 bytes, 3.9
seconds) converted to guitar.mid
piano.wav (35664 bytes, 3.2 seconds)
converted to piano.mid (259 bytes)
voice.wav (44122 bytes, 3.9 seconds)
converted to voice.mid (298 bytes)
whistle.wav (39534 bytes, 3.5
seconds) converted to whistle.mid
The unregistered version of our software allows you to
evaluate the program features before registering it. If you decide to continue using our
software after evaluation, you must register it.
AKoff Guitar Assistant
Buy now ($19) Free Download (this version is
AKoff Guitar Assistant is designed to assist in visual tuning
a guitar with microphone or an electrical guitar connected to PCs sound card. It
analyzes in real time a stream of audio signals from Wave input of your sound card and
calculates the main frequency. This frequency is shown by a pointer on graphic guitar
signature stamp (frets), comparing it to the proper frequency. Tuning a string now simply
means centering the pointer on the appropriate graphic fret.
AKoff Guitar Assistant recognizes monophonic sound. This means you
won't get the appropriated results if you try to play chords. The recognition is
influenced by quality of your sound card and microphone.
The complicated mathematical algorithms of the analysis of digital
signals require a great amount of calculations and consequently a fast computer. AKoff
Guitar Assistant only works reliably on Pentium 133 and higher processors. On weaker
machines the incorrect working or dead halt of the program may occure which is removed
through pressing Ctrl-Alt-Del keys.
What is Music Recognition?
In a few words music recognition is mathematical analysis
of an audio signal (usually in WAVE format) and its conversion into musical notation
(usually in MIDI format). This is a very hard artificial intelligence problem. For
comparison, the problem of recognition of scanned text (OCR - Optical Character
Recognition) is solved with 95% accuracy - it is an average exactitude of recognition of
the programs of the given class. The programs of speech recognition already work with
70-80% accuracy, whereas the systems of music recognition work with 60-70% accuracy but
only for a single voice melody (one note at a time). For polyphonic music the accuracy is
To create a MIDI file for a song recorded in WAVE format
a musician must determine pitch, velocity and duration of each note being played and
record these parameters into a sequence of MIDI events. A music recognition software must
do the same things. Even for a single instrument song it is not a simple task, because a
WAVE recording contains waveform signals and doesn't contain any music specific data.
In general cases the variety of music timbres, harmonic
constructions and transitions make it impossible to create a mathematical algorithm for
precise reconstruction of a music score from the audio sources. It is hard to recognize
audio data which contains many instruments, drums and percussions or clipping signals,
unstable pitch sounds and background noises. However, in many cases AKoff Music Composer will produce a
MIDI material that represents the basic melody and chords of recognized music. You can download and listen to source
wave-files and recognized midi-results.
WAVE and MIDI Formats
The difference between WAVE and MIDI formats consists in
representation of sound and music. WAVE format is digital recording of any sound
(including speech) and MIDI format is principally sequence of notes (or MIDI events). The
relations are approximately the same as between sounded speech and printed text.
A WAVE file is the recording of a sound wave. It is the mix of all the given sounds
(instruments, voices, background noises) you could have heard at the moment of recording.
So you can record, for example, human voice in WAVE format, but you cannot edit any note
or change any instrument in music recorded in a WAVE file. The Standard Windows PCM WAVE
format contains only Pulse Code Modulation data without compression. PCM format is the
only kind that saves the entire wave completely with no data loss.
There are many other formats for audio recording. They
differ from each other by compression algorithms and can be referred to one group. The
conversion from one format into another is very simple. There are many sound editors which
allow one to do this.
The following is a list of some audio formats with file
extensions: Standard Windows PCM waveform (.WAV) Microsoft ADPCM waveform (.WAV) MPEG
Layer (.MP2, .MP3) RealAudio (.RA) Sound Blaster voice file format (.VOC) Apple AIFF
format (.AIF, .SND) WMA, VQF and many others.
MIDI (Musical Instrument Digital Interface) format is a sequence of commands to control
one or more pieces of musical hardware or software such as synthesizers or sequencers.
These commands are not sounds, they are instructions to do something (mostly to generate
sound). For example: select Instrument #1 (Acoustic Grand Piano), play Note #60 (C5) with
Velocity #127. So you cannot represent, for example, human speech in MIDI format, but you
can edit any note or change any instrument in music recorded in MIDI file.
MIDI to WAVE conversion
Music recorded in MIDI format can be easily transformed to WAVE format. You can play MIDI
files on an appropriate player and record reproduced music in a sound editor. The size of
a WAVE file will be larger than the same music file represented in MIDI format. The
quality of music will be determined by MIDI capabilities of your sound card and
professionalism of the musician creating the source MIDI file. There are programs
converting MIDI files into WAVE using only their own timbres of MIDI instruments
The reconversion from WAVE to MIDI is the music
recognition problem which up until now has no qualitative solution (with 100% accuracy).