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.

The Timbre Toolbox: extracting audio descriptors from musical signals.

Abstract: The analysis of musical signals to extract audio descriptors that can potentially characterize their timbre has been disparate and often too focused on a particular small set of sounds. The Timbre Toolbox provides a comprehensive set of descriptors that can be useful in perceptual research, as well as in music information retrieval and machine-learning approaches to content-based retrieval in large sound databases. Sound events are first analyzed in terms of various input representations (short-term Fourier transform, harmonic sinusoidal components, an auditory model based on the equivalent rectangular bandwidth concept, the energy envelope). A large number of audio descriptors are then derived from each of these representations to capture temporal, spectral, spectrotemporal, and energetic properties of the sound events. Some descriptors are global, providing a single value for the whole sound event, whereas others are time-varying. Robust descriptive statistics are used to characterize the time-varying descriptors. To examine the information redundancy across audio descriptors, correlational analysis followed by hierarchical clustering is performed. This analysis suggests ten classes of relatively independent audio descriptors, showing that the Timbre Toolbox is a multidimensional instrument for the measurement of the acoustical structure of complex sound signals.

Proximity synchronization of audio content among multiple playback and storage devices

Abstract: A wireless communication system and in particular to a wireless communication system for digital audio players that provides for increased functionality, such as communication, interaction and synchronization between a computing platform and various mobile, portable or fixed digital audio players, as well as providing a communication link between the various digital audio players themselves. The computing platform may act, for example, through a wireless network or wireless communication platform, to control the digital audio players; to act as a cache of digital audio data for the digital audio players; as well as provide a gateway to the Internet to enable the digital audio players to access additional digital audio content and other information. The computing platform may also be used to automatically update digital audio content on the digital audio players; synchronize digital audio content and playlists between digital audio players; and automatically continue a particular playlist as the user moves from one digital audio player to another.

Signal processing and compression with wavelet packets

Abstract: Wavelet packets are a versatile collection of functions generalizing the compactly supported wavelets of Daubechies. They are used to analyze and manipulate signals such as sound and images. We describe a library of such waveforms and demonstrate a few of their analytic properties. We also describe an algorithm to chose a best basis subset, tailored to fit a specific signal or class of signals. We apply this algorithm to two signal processing tasks: acoustic signal compression, and feature extraction in certain images.

Method and system for mitigating delay in receiving audio stream during production of sound from audio stream

Abstract: A communication component modifies production of an audio waveform at determined modification segments to thereby mitigate the effects of a delay in processing and/or receiving a subsequent audio waveform. The audio waveform and/or data associated with the audio waveform are analyzed to identify the modification segments based on characteristics of the audio waveform and/or data associated therewith. The modification segments show where the production of the audio waveform may be modified without substantially affecting the clarity of the sound or audio. In one embodiment, the invention modifies the sound production at the identified modification segments to extend production time and thereby mitigate the effects of delay in receiving and/or processing a subsequent audio waveform for production.

Method and apparatus for audio-visual speech detection and recognition

Abstract: Techniques for providing speech recognition comprise the steps of processing a video signal associated with an arbitrary content video source, processing an audio signal associated with the video signal, and recognizing at least a portion of the processed audio signal, using at least a portion of the processed video signal, to generate an output signal representative of the audio signal.