Method for live public address, in a helmet, taking into account the auditory perception characteristics of the listener
A public address method for live broadcast, in a helmet, of an audio signal conditioned from a plurality of raw audio channels, includes a pre-processing phase including the operations that consist of taking into account characteristics of the auditory perception of the listener; correcting each channel as a function of the characteristics of the auditory perception of the listener; a mixing phase including the production, from the channels thus pre-processed, of a mixed audio signal; a post-processing phase including the operations that consist of: measuring the sound level of a background noise; correcting the mixed audio signal as a function of the sound level of the background noise; a phase of reproducing, in the helmet, the conditioned audio signal resulting from post-processing.
1. A public address method for live musical broadcast, in at least one speaker equipping a helmet headphones worn or intended to be worn by a listener and comprising a speaker, of an audio signal produced from a plurality of raw audio channels, the method comprising:
a pre-processing phase comprising:
taking into account characteristics of an auditory perception of the listener, who suffers from hearing loss, the auditory perception being based on one or more isosonic curves associated with said listener;
correcting each channel as a function of the characteristics of the auditory perception of the listener;
a mixing phase comprising production, from the pre-processed plurality of channels, of a mixed audio signal;
a post-processing phase comprising:
measuring a sound level of a background noise penetrating into the helmet headphones;
correcting the mixed audio signal as a function of the sound level of the background noise to produce the audio signal;
a phase of reproducing, in the helmet headphones, the audio signal resulting from the post-processing phase.
2. The method according to claim 1 , wherein the correction applied to each channel comprises a frequency correction.
3. The method according to claim 1 , wherein the correction applied to each channel comprises a time correction.
4. The method according to claim 1 , wherein the correction applied to each channel comprises a level correction.
5. The method according to claim 1 , wherein the correction applied to each channel comprises one or more processings chosen from a clipping, a compression, a gain.
6. The method according to claim 1 , wherein the pre-processing phase comprises:
sampling each channel in frequency,
selecting on the channel one or more frequency ranges;
applying to the respective channel of the plurality of channels a processing in the selected frequency range or ranges, as a function of the characteristics of the auditory perception of the listener in said frequency range or ranges.
7. The method according to claim 1 , wherein, in the pre-processing phase, taking into account characteristics of the auditory perception of the listener comprises taking into account or determining an auditory comfort level.
8. The method according to claim 7 , wherein, in the pre-processing phase, the correcting of each channel comprises bringing each respective channel to the auditory comfort level of the listener.
9. The method according to claim 1 , further comprising, between the pre-processing phase and the mixing phase, a panoramic processing operation in order to form, from each pre-processed channel, a left track and a right track.
10. The method according to claim 9 , further comprising, between the panoramic processing and the mixing phase, an amplification operation of the left tracks and of the right tracks resulting from each channel.
11. The method according to claim 10 , wherein the mixing phase is conducted independently for the left tracks and for the right tracks, in such a way as to produce a left mixed audio signal and a right mixed audio signal.
12. The method according to claim 11 , wherein the post-processing phase is applied to the left mixed audio signal and to the right mixed audio signal in order to produce a left conditioned audio signal and a right conditioned audio signal.
13. The method according to claim 1 , wherein, in the post-processing phase, the measurement of the sound level of the background noise penetrating into the headphones is carried out by means of a microphone integrated into the headphones.
14. The method according to claim 1 , wherein, in the post-processing phase:
a pain threshold for the listener is taken into account or determined;
the mixed audio signal is corrected in such a way that a global sound level in the headphones, comprising the mixed audio signal and the background noise penetrating into the headphones, is at any instant less than the pain threshold of the listener.
15. The method according to claim 1 , wherein the post-processing phase comprises the application of a delay to the mixed audio signal.