Audio signal processing

About: Audio signal processing is a research topic. Over the lifetime, 21463 publications have been published within this topic receiving 319597 citations. The topic is also known as: audio processing & Acoustic signal processing.

User adjustable volume control that accommodates hearing

Abstract: The present invention is a method for mixing audio signals based on the preference from hearing impaired listeners, as well as non-hearing impaired listeners, without forcing hearing impaired individuals to employ special hearing-impaired equipment. A user activated controller (10, 11) controls a mixture of a preferred audio signal and a remaining audio signal across a range sufficiently wide enough to encompass all individuals. The preferred audio is recorded and maintained separated from all remaining audio and delivered to the listener in a manner that maintains this separation. The controller (10, 11) enables the user to specify a range about the ratio in which the audio may vary, which permits the listener to expand the audio across a continuous range to whatever dynamic range his hearing can accommodate. The controller (10, 11) automatically adjusts to changes in incoming audio. The controller (10, 11) can react to relatively slowly moving changes or prevent short bursts of sound in remaining audio from modifying the signal levels. The combination of the ability to control the mixing ratio and to specify the dynamic range of the ratio in which the audio may vary, coupled with the ability to automatically adjust the signal levels in response to sudden changes in incoming audio, provides a powerful user capability that truly optimizes the listening experience for any listener.

Integrated cellular telephone and vehicular audio system

Abstract: An output transducer and amplifier are shared between an audio system and a cellular Phone in an automotive vehicle. An interface arbitrates between the program audio signals and the phone audio signals to select or deselect each of the audio signals depending on the status of each audio source. When only one source is in use then normally the audio signals from that source are selected. If both sources are turned on but a phone call is not in progress, then audio signals from both sources are simultaneously presented to the output transducers after summing. When a call is in progress, only the phone audio signals are selected.

Noise reduction processing arrangement for microphone arrays

Abstract: A sound processing arrangement couples sound from a prescribed environment through a fixed microphone array to a signal processing arrangement having a specifiable preferred sound source location. The microphone pickup signals are combined with a set of weighting signals to adjust the directional response pattern in successive analysis time intervals. The weighting signals are modified in each analysis time interval so that the total acoustic signal power of the signal processing arrangement output signal is decreased toward a minimum while substantially unity power transfer of sound signals from said preferred location is maintained at all frequencies over a prescribed frequency range. In this way, the preferred source location is in the main beam while unwanted sound source locations are at the null points of the adjusted directional response pattern.

Method and system for synchronizing audio processing modules

Abstract: Embodiments of the present invention provide an audio system having wholly independent audio processing modules. The audio system includes a plurality of audio processing modules, a clock manager, a sample rate converter and a buffer. The audio processing modules are communicatively coupled to the clock manager and the buffer. The sample rate converter is communicatively coupled to the clock manager and the buffer. The buffer provides for storing audio data generated and consumed by the audio processing modules. The clock manager provides for determining the clock source of each audio processing module. The clock manager also provides for configuring the audio processing modules and the sample rate converter as a function the clock source of each audio processing module. The sample rate converter provides for synchronizing a flow rate of audio data generated by a first audio processing module and a flow rate of audio data consumed by a second audio processing module, when the clock source of the first and second audio processing modules are different.

Audio Events Detection in Public Transport Vehicle

Abstract: This paper addresses the problem of automatic audio analysis for aided surveillance application in public transport. The aim of such application is to detect critical situations and to warn the control room. We propose a comparative study of two methods of modelisation/classification of acoustical segments. The problem is quite similar to the 'audio indexing' framework, nevertheless the environment here is very noisy. We present two general frameworks based on Gaussian model mixture (GMM) and support vector machine (SVM) to achieve shout detection in railway embedded environment