Device and method for generating a real time music accompaniment for multi-modal music

1. A device for generating a real time music accompaniment, said device comprising:

circuitry configured to

receive pieces of music played by a musician,

classify the pieces of music into one of at least three different music modes, said at least three different music modes including at least a solo mode, a bass mode and a harmony mode,

calculate a chord transformation cost, the chord transformation cost being a sum c(τ j )+c(σ i ) of a chord transposition cost c(τ j ) due to transpositions between one or more recorded pieces of music and the received pieces of music and a chord substitution cost c(σ i ) due to substitutions between the one or more recorded pieces of music and the received pieces of music, wherein the chord transposition cost c(τ j ) is calculated based on a number of semitones down or up from the received pieces of music to the one or more recorded pieces of music, the chord transposition cost c(τ j ) increasing as the number of the semitones increases, and the chord substitution cost c(σ i ) is calculated based on predetermined rules for chord substitution, each of the predetermined rules having each cost such that a first predetermined rule having more harmonic quality has lower cost than a second predetermined rule having less harmonic quality,

select one or more recorded pieces of music having the chord transformation cost under a predetermined maximum chord transformation cost as real time music accompaniment to an actually played piece of music, wherein said one or more selected pieces of music are selected to be in a different one of said at least three music modes than the actually played piece of music, and

output the one or more selected pieces of music.

2. The device as claimed in claim 1 ,

wherein the circuitry is further configured to analyze a received piece of music to obtain a music piece description comprising one or more characteristics of the analyzed piece of music, and

wherein said circuitry is configured to take a music piece description of an actually played piece of music and of recorded pieces of music into account in the selection of one or more recorded pieces of music as real time music accompaniment.

3. The device as claimed in claim 2 ,

wherein said circuitry is configured to record said music piece description along with the corresponding piece of music.

4. The device as claimed in claim 2 ,

wherein said circuitry is configured to obtain a music piece description comprising one or more of pitch, bar, key, tempo, distribution of energy, average energy, peaks of energy, number of peaks, spectral centroid, energy level, style, chords, volume, density of notes, number of notes, mean pitch, mean interval, highest pitch, lowest pitch, pitch variety, harmony duration, melody duration, interval duration, chord symbols, scales, chord extensions, relative roots, zone, type of instrument(s) and tune of an analyzed piece of music.

5. The device as claimed in claim 2 ,

wherein the circuitry is further configured to receive or select a chord grid comprising a plurality of chords,

wherein said circuitry is configured to obtain a music piece description comprising at least chords of beats of the analyzed piece of music, and

wherein said circuitry is configured to take the chord grid of an actually played piece of music and the music piece description of recorded pieces of music into account in the selection of one or more recorded pieces of music as real time music accompaniment.

6. The device as claimed in claim 1 ,

wherein the circuitry is further configured to

receive or select a tempo of played music, and

take the received or selected tempo of an actually played piece of music into account in the selection of one or more recorded pieces of music as real time music accompaniment.

7. The device as claimed in claim 1 ,

wherein the circuitry is further configured to control said device to switch between recording and playback.

8. A method for generating a real time music accompaniment, said method comprising:

receiving, using circuitry, pieces of music played by a musician,

classifying, using the circuitry, the received pieces of music into one of at least three different music modes, said at least three different music modes including at least a solo mode, a bass mode and a harmony mode,

calculating, using the circuitry, a chord transformation cost, the chord transformation cost being a sum c(τ j )+c(σ i ) of a chord transposition cost c(τ j ) due to transpositions between the one or more recorded pieces of music and the received pieces of music and a chord substitution cost c(σ i ) due to substitutions between the one or more recorded pieces of music and the received pieces of music, wherein the chord transposition cost c(τ j ) is calculated based on a number of semitones down or up from the received pieces of music to the one or more recorded pieces of music, the chord transposition cost c(τ j ) increasing as the number of the semitones increases, and the chord substitution cost c(σ i ) is calculated based on predetermined rules for chord substitution, each of the predetermined rules having each cost such that a first predetermined rule having more harmonic quality has lower cost than a second predetermined rule having less harmonic quality,

selecting, using the circuitry, one or more recorded pieces of music having the chord transformation cost under a predetermined maximum chord transformation cost as real time music accompaniment to an actually played piece of music, wherein said one or more selected pieces of music are selected to be in a different one of said at least three music modes than the actually played piece of music, and

outputting, using the circuitry, the selected pieces of music.

9. A non-transitory computer-readable recording medium that stores therein a computer program product, which, when executed by a processor, causes the method according to claim 8 , to be performed.

10. The device as claimed in claim 1 ,

wherein the circuitry is configured to perform the substitutions based on a list of substitutions.