Key Scape

number of cells in bottom row (<80)
number of rows (<40)
midi file (<6000 notes)

This application returns a key anlysis of a midi file that can be uploaded with the form to the left. The output is a table (see picture below) where each row represents an analysis of the complete midi file. Time goes from left to right and is measured in quarter beats (indicated below the picture every tenth cell). Each cell shows a key analysis of a time window centered around the cell. The window width is the same for all cells in a row and is shown to the left of the row (in quarter beats). The shading of a cell represents the confidence in the key (dark shades indicate low confidence). When two keys are close together on the line of fifth their colors are close together in rainbow order. The top row has one cell, where the analysis window covers the complete midi file. In the bottom row the width of the analysis window is is twice the time spacing between the cells. This (horizontal) time spacing is the same between all cells and is shown below the picture (in quarter beats). When more cells are specified in the form, the spacing decreases. (number of cells * spacing = duration of the midi file). The key analysis follows the algorithm proposed by C.L. Krumhansl. The idea of the key scape is due to C.S. Sapp.