Timbre fitting method and system based on time-varying multi-segment spectrum

A timbre fitting system based on time-varying multi-segment spectrum for fitting a timbre of a string musical instrument, comprising:

• an input device for obtaining an audio signal of a source musical instrument and an audio signal of a target musical instrument;
• and
• a segmented multi-model compensation module configured to:
• learn a timbre of a source musical instrument and a timbre of a target musical instrument;
• and
• establish a first multi-segment model of a sound feature of the source musical instrument and a second multi-segment model of the sound feature of the target musical instrument;
• wherein each sound feature is set to be based on a maximum amplitude of the audio signals played the same sequence on the target musical instrument and the source musical instrument;
• wherein each audio signal of the sequence is configured to be divided into multiple segments according to the amplitude of the audio signal;
• wherein each sound feature comprises a plurality of frequency spectrums of notes within each amplitude range;
• wherein the segmented multi-model compensation module is configured to establish a multi-model structure with time-varying gain based on the difference between the sound feature of the source musical instrument and the sound feature of the target musical instrument;
• wherein multi-model structure with time-varying gain is configured to minimize the difference between the sound feature of the source instrument and the sound feature of the target instrument;
• and
• wherein each of the plurality of frequency spectrums of notes within each amplitude range is obtained by summing each frame frequency data within the amplitude range through a weighting coefficient, the weighting coefficient is obtained by the following formula,
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• the letter x stands for a signal amplitude, the letter s stands for a threshold, the letter f stands for a nonlinear factor, and the letter stands for m stands for the weighted coefficient.

A timbre fitting method based on time-varying multi-segment spectrum for fitting a timbre of a string musical instrument, comprising:

• obtaining an audio signal of a source musical instrument and an audio signal of a target musical instrument;
• learning a timbre of a source musical instrument and a timbre of a target musical instrument according the audio signals of the source and target musical instruments;
• establishing a first multi-segment model with a sound feature of the source musical instrument and establishing a second multi-segment model with a sound feature of the target musical instrument;
• and
• establishing a multi-model structure with time-varying gain based on the difference between the first multi-segment model and the second multi-segment model;
• wherein each of the plurality of frequency spectrums of notes within each amplitude range is obtained by summing each frame frequency data within the amplitude range through a weighting coefficient, the weighting coefficient is obtained by the following formula,
• m
• =
• arctan
• ⁡
• [
• (
• x
• -
• s
• )
• ⋆
• f
• ]
• -
• arctan
• ⁡
• [
• (
• -
• s
• )
• ⋆
• f
• ]
• arctan
• ⁡
• [
• (
• 1
• -
• s
• )
• ⋆
• f
• ]
• -
• arctan
• ⁡
• [
• (
• -
• s
• )
• ⋆
• f
• ]
• ,
• the letter x stands for a signal amplitude, the letter s stands for a threshold, the letter f stands for a nonlinear factor, and the letter stands for m stands for the weighted coefficient.