We present an optimization of the voltage scaling algorithm in low power audio class G amplifier for headphones application to allow longer playback time. The optimization approach minimizes the voltage difference between the internal audio amplifier power supply and its output signal over a large range of operating conditions. The modeling is based on a behavioral model enabling accurate and r...

A hierarchical system for audio classi cation and retrieval based on audio content analysis is presented in this paper. The system consists of three stages. The rst stage is called the coarse-level audio classi cation and segmentation, where audio recordings are classi ed and segmented into speech, music, several types of environmental sounds, and silence, based on morphological and statistical...

Steganography is the art of message hiding in a cover signal without attracting attention. The requirements of the good steganography algorithm are security, capacity, robustness and imperceptibility, all them are contradictory, therefore, satisfying all together is not easy especially in audio cover signal because human auditory system (HAS) has high sensitivity to audio modification. In this ...

An algorithm for audio key finding that participated in the 2005 Music Information Retrieval Evaluation Exchange (MIREX 2005) is presented. This algorithm takes a sound file that contains polyphonic audio as input and outputs a key estimate for this file. It is designed to operate on short fragments of audio taken from the beginnings of musical works. The algorithm consists of three stages: chr...

By building a wired passive stylus we have added pressure sensitivity to existing capacitive touch screen devices for less than $10 in materials, about 1/10th the cost of existing solutions. The stylus makes use of the built-in audio interface that is available on most smartphones and tablets on the market today. Limitations of the device include the physical constraint of wires, the occupation...

This paper presents a joint speech and audio coding algorithm combining sinusoidal modeling and a perceptually adapted Wavelet Packet Transform (WPT). The input signal is limited to the band of 50-7000 Hz, and sampled at 16 kHz. The sinusoidal modeling uses a Sinusoidal Similarity Measure (SSM) to find stable sinusoidal components. A novel pitch harmonics based encoding is applied to encode the...

The means for providing AGC for the overall receiver are important aspects of the block diagram design for an HF SSB receiver. The receiver is operationally required to have nearly constant audio output as the signal input ranges from the 1-μV region to perhaps 1 V or more and to do so without having loop oscillation or distorting the received signal. A receiver primarily designed to be used by...

Identification and compensation purposes of nonlinear systems are of interest for many audio processing applications. The analysis of systems under test must be done through realistic audio inputs in order to capture different aspects of the nonlinearity. However, the Gaussianity of the tested signal, is a desirable factor because it guarantees easy implementation and good performances for the ...

Although field-collected recordings typically contain multiple simultaneously vocalizing birds of different species, acoustic species classification in this setting has received little study so far. This work formulates the problem of classifying the set of species present in an audio recording using the multi-instance multi-label (MIML) framework for machine learning, and proposes a MIML bag g...

In this paper we evaluate two methods for key estimation from polyphonic audio recordings. Our goal is to compare between a strategy using a cognition-inspired model and several machine learning techniques to find a model for tonality (mode and key note) determination of polyphonic music from audio files. Both approaches have as an input a vector of values related to the intensity of each of th...