Patent Document ID: 20170365244
Application ID: 15534619
Patent Flag: 0

Claim One:
1. A method for processing an original time-domain digital audio signal wherein said signal is split into a plurality of narrow-band time-domain digital audio signals confined to specific frequency bands, short-term segments of which are temporarily stored in memory, the method comprising: using signal processing algorithms, extracting from said segments of said narrow-band time-domain signals, in a fixed sequence or upon request from a decision-making algorithm, narrow-band time-domain features such as average power, and/or average amplitude, and/or instantaneous frequency or characteristics derived therefrom, and/or instantaneous period or characteristics derived therefrom, and/or instantaneous envelope or characteristics derived therefrom, and/or the time-domain positions of zero-crossings derived from sample values, directly or by interpolation, or characteristics derived therefrom, using said decision-making algorithm, making tentative or final decisions about a type of occupancy of frequency bands resulting from said narrow-band time-domain features, using said decision-making algorithm, requesting from said signal processing algorithms further specific feature extractions from specific short-term segments and makes tentative or final decisions about the type of occupancy of frequency bands resulting from the requested features, using said decision-making algorithm, storing the tentative and final decisions about band occupancy for processing together with results from later short-term segments, and using said decision-making algorithm, outputting final decisions derived from current and past short-segments in the form of a set of notes having been played over some recent time interval, together with information relating to the timing of each note from the set.