Signaturing methods and apparatus as described. In one example, a signaturing method includes capturing an audio signal, applying a first window function to a portion of the captured audio signal to produce a first windowed audio block, applying a second window function to the portion of the captured audio signal to produce a second windowed audio block, determining a first characteristic of a band of frequencies in the first windowed audio block, determining a second characteristic of the band of frequencies in the second windowed audio block, comparing the first characteristic to the second characteristic, and assigning a signature bit representative of the portion of the captured audio signal based on the comparison of the first characteristic and the second characteristic. Other examples are described.