Sanjay's Piano application

This Java piano offers the following features:

Use your computer's QWERTY keyboard to play the piano
External MIDI keyboard support (needs Java 1.4.2)
Scaleable scrollable image of keyboard, over which you can click or drag over to play notes
Select from your sound card's instrument banks, modify MIDI controllers
Limit to notes from given scales - test 10 scale patterns in every key
Choose your temperament, including 1/4 comma mean tone, Pythagorean and Werckmeister; transpose
Chord recognition - analyses and suggests names for chords you play
Select and play chords from a comprehensive list of classical and jazz chords; alter chord voicing and inversion.
Experimental feature: analyses the counterpoint as you play. Spots parallel fifths, octaves etc.
Enter, load or save a sequence of chords, and play them back. Automatically chooses appropriate voicings and bassline depending on the chords's context. Optional drum accompaniment.
Experimental feature: listens through the computer's microphone, or selected audio channel, and displays what it hears as notes on the keyboard.
Memory - stores everything that has been played in bank of tracks, automatically segmented into chunks and organised by time of playing. Automatically persists on starting and closing the program
Export and import midi files
Scripts - directly control the keyboard using a programming language
Configurable look and feel

Click anywhere on the piano, then press keys on your keyboard to play notes.

Keyboard layout:

 a s   f g h   k l   ' 1 2   4 5   7 8 9   - =
\ Z X C V B N M , . / t Q W E R T Y U I O P [ ]

Options:

Filter keyboard notes: disallows keypresses that do not fit into the currently selected scale.
Filter MIDI input: blocks MIDI events from external source that do not fit into the currently selected scale.

Temperament

The tonal centre is the scale selected in the Scale tab.