Method of encoding, method of decoding, encoder, and decoder of an audio signal

An audio signal encoding method comprising the steps of:

• collecting audio signal samples,
• determining sinusoidal components in subsequent frames,
• estimation of value of amplitude and value of frequency of sinusoidal components in each frame,
• compression of the values of amplitude and the values of frequency to obtain output data,
• characterized in that
• compression of the values of the amplitudes and values of frequency includes steps of:
• forming rows of values of amplitudes corresponding to subsequent frames and forming rows of frequencies corresponding to sinusoidal components in subsequent frames to obtain sinusoidal trajectories
• splitting particular trajectories into segments having individual lengths greater than one frame,
• representing the amplitudes and frequencies in logarithmic scale
• transforming amplitudes represented in logarithmic scale over the segments to the frequency domain by means of orthogonal transform and transforming frequencies represented in logarithmic scale over the segments to the frequency domain by means of orthogonal transform to obtain transform coefficients,
• quantization of the transform coefficients with quantization levels to obtain quantized transform coefficients and
• selection in the segments of the quantized transform coefficients to be encoded and forming arrays of their indices and discarding the remaining quantized transform coefficients,
• entropy encoding of only selected quantized transform coefficients together with the arrays of their indices to obtain output data.