Abstract: A method for equalizing an audio frequency signal broadcast in a broadcasting environment. Such a method includes: estimating a frequency profile of a noise signal representing a background noise present in the broadcasting environment, based on, on the one hand, a signal captured by at least one microphone implemented in the broadcasting environment and, on the other hand, the audio frequency signal; determining a desired frequency profile for the broadcast audio frequency signal; determining an acoustic frequency mask representing, for each frequency component, a difference between the frequency profile of the noise signal and the desired frequency profile; and equalizing the audio frequency signal via a weighting of a spectrum of the audio frequency signal by applying a frequency weighting mask that is a function of the acoustic frequency mask, delivering the equalized audio frequency signal.

Abstract: A method for reducing parasitic vibrations of a loudspeaker environment while maintaining the perception of the low frequencies of an original electric sound signal for broadcast after processing by the loudspeaker having a cut-off frequency. A vibration frequency band is identified that causes the loudspeaker to vibrate. A low frequency band of the original sound signal having a frequency close to the cut-off frequency of the loudspeaker is identified as an upper limit. At least one harmonic signal from the isolated low frequency band of the original sound signal is generated. The original sound signal and the harmonic signal are combined to obtain a recombined signal. The vibration frequency band is removed from the recombined signal to obtain a signal for broadcast by the loudspeaker.

Abstract: A method of generating left (Ls) and right (Rs) sound signals known as “surround” signals from a stereo sound signal composed of a left sound signal and of a right sound signal. One of the stereo signals is subtracted from the other signal with the aid of a subtraction module to obtain a single subtraction signal (LR) in which the correlated and in-phase components of the stereo signals (L, R) have been removed. A right sound signal (Rs) and a left sound signal (Ls) are generated from the subtraction signal (L?R), these signals being decorrelated with respect to one another and corresponding respectively to the right and left sound “surround” signals. These “surround” signals (Ls, Rs) intend for broadcast on the rear channels of an acoustic system.

Abstract: A method for encoding and decoding a digital audio signal composed of an original right-hand signal (SDO) and an original left-hand signal (SGO). The method combines the original right-hand signal (SDO) and the original left-hand signal (SGO) to obtain a single combined signal (SC), encodes the combined signal (SC) using a standard encoder to obtain a compressed combined signal (SCC), and decodes the compressed combined signal (SCC) using a standard decoder (8) to obtain a decompressed combined signal (SCD). After decoding, the method generates a reconstructed right-hand signal (SDR) and a reconstructed left-hand signal (SGR) from the decompressed combined signal (SCD), which are de-correlated from each other. Also, a treble-generating module enables the high-frequency component (SHF) of the right-hand (SDR) or left-hand (SGR) signals to be recreated, which signals had been deleted as a result of the compression.

Abstract: A method and device for normalizing the power of an electrical signal, referred to as an original sound signal S1. The method detects the envelope of the original sound signal S1 and compares the power value of the envelope signal S2 with a threshold value K1. The gain signal S3 is calculated in accordance with the comparison and smoothed to obtain a smoothed gain signal S4. The original sound signal S1 is delayed by a delay T. The smoothed gain signal S4 is applied to the delayed original sound signal S1 to obtain a normalized sound signal S5. The method is suitable for a source including a plurality of channels.

Abstract: A method of optimizing stereo reception for an analog radio by applying the demodulated right sound signal (SD) and left sound signal (SG) as input to a decorrelation module having a variable decorrelation rate. The decorrelation rate of the decorrelation module is modified as a function of the reception quality coefficient “alpha” provided by the radio. The decorrelation module applies a higher decorrelation rate for a smaller reception quality coefficient “alpha” and applies a lower decorrelation rate for a larger reception quality coefficient “alpha. Also, a module for generating high-pitched sounds to recreate the high-frequency component (SHF) of the right or left sound signals which has been removed in the event of poor reception.

Abstract: A method and device for normalizing the power of an electrical signal, referred to as an original sound signal S1. The method detects the envelope of the original sound signal S1 and compares the power value of the envelope signal S2 with a threshold value K1. The gain signal S3 is calculated in accordance with the comparison and smoothed to obtain a smoothed gain signal S4. The original sound signal S1 is delayed by a delay T. The smoothed gain signal S4 is applied to the delayed original sound signal S1 to obtain a normalized sound signal S5. The method is suitable for a source including a plurality of channels.

Abstract: A method for reducing parasitic vibrations of a loudspeaker environment while maintaining the perception of the low frequencies of an original electric sound signal for broadcast after processing by the loudspeaker having a cut-off frequency. A vibration frequency band is identified that causes the loudspeaker to vibrate. A low frequency band of the original sound signal having a frequency close to the cut-off frequency of the loudspeaker is identified as an upper limit. At least one harmonic signal from the isolated low frequency band of the original sound signal is generated. The original sound signal and the harmonic signal are combined to obtain a recombined signal. The vibration frequency band is removed from the recombined signal to obtain a signal for broadcast by the loudspeaker.

Abstract: A method of optimizing stereo reception for an analog radio by applying the demodulated right sound signal (SD) and left sound signal (SG) as input to a decorrelation module having a variable decorrelation rate. The decorrelation rate of the decorrelation module is modified as a function of the reception quality coefficient “alpha” provided by the radio. The decorrelation module applies a higher decorrelation rate for a smaller reception quality coefficient “alpha” and applies a lower decorrelation rate for a larger reception quality coefficient “alpha. Also, a module for generating high-pitched sounds to recreate the high-frequency component (SHF) of the right or left sound signals which has been removed in the event of poor reception.

Abstract: A method for encoding and decoding a digital audio signal composed of an original right-hand signal (SDO) and an original left-hand signal (SGO). The method combines the original right-hand signal (SDO) and the original left-hand signal (SGO) to obtain a single combined signal (SC), encodes the combined signal (SC) using a standard encoder to obtain a compressed combined signal (SCC), and decodes the compressed combined signal (SCC) using a standard decoder (8) to obtain a decompressed combined signal (SCD). After decoding, the method generates a reconstructed right-hand signal (SDR) and a reconstructed left-hand signal (SGR) from the decompressed combined signal (SCD), which are de-correlated from each other. Also, a treble-generating module enables the high-frequency component (SHF) of the right-hand (SDR) or left-hand (SGR) signals to be recreated, which signals had been deleted as a result of the compression.

Abstract: A method of generating left (Ls) and right (Rs) sound signals known as “surround” signals from a stereo sound signal composed of a left sound signal and of a right sound signal. One of the stereo signals is subtracted from the other signal with the aid of a subtraction module to obtain a single subtraction signal (LR) in which the correlated and in-phase components of the stereo signals (L, R) have been removed. A right sound signal (Rs) and a left sound signal (Ls) are generated from the subtraction signal (L?R), these signals being decorrelated with respect to one another and corresponding respectively to the right and left sound “surround” signals. These “surround” signals (Ls, Rs) intend for broadcast on the rear channels of an acoustic system.