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[tONaRT] key detection

[tONaRT] key detection automatically determines the key signature of any audio input signal, either monophonic or polyphonic. Key recognition can be useful in mixing applications to check if the keys of different tracks are "compatible" or for automatic generation of high-level meta data information (e.g. ID-Tags). As a special feature, [tONaRT] also detects the tuning frequency, or standard (concert) pitch of the input signal.

The input signal is analyzed about its tonal content (pitches) via a filterbank. The filterbank's mid-frequencies are constantly adapted due to the detected standard pitch to increase the detection accuracy. The resulting pitch distribution is analyzed with a sophisticated probability model to check for the most likely key acc. the detected pitch strengths. The detection accuracy is ca. 80 percent, compared to a random detection accuracy of only 4 percent. When classifying related keys as correctly detected, the detection accuracy is well above 90 percent, making [tONaRT] a reliable and robust technology for automatic key detection. The standard pitch detection has an accuracy of app. 1-2Hz at 440Hz.


[tONaRT] key detection engine is successfully being integrated in (listed alphabetically):

pricing & licensing

Please visit our licensing page for more information. We are happy to discuss license fees with you in personal communication.