Abstract: This disclosure is directed to techniques for controlling the execution speed of a processor that executes audio processing algorithms. In some examples, the execution speed of the processor may be controlled based on one or more delay parameters that are obtained from querying one or more tasks that execute the audio processing algorithms. The delay parameters that are returned by the tasks in response to the queries may, in some examples, be dependent upon one or more algorithm-specific parameters that are used to configure the audio processing algorithms. The techniques of this disclosure may be used to reduce the amount of power consumed by a processor that is configured to execute one or more audio processing algorithms in an audio communication device, which may be particularly useful in audio communication devices where power resources are limited, such as, e.g., a mobile phone.

Abstract: This disclosure is directed to techniques for controlling the execution speed of a processor that executes audio processing algorithms. In some examples, the execution speed of the processor may be controlled based on one or more delay parameters that are obtained from querying one or more tasks that execute the audio processing algorithms. The delay parameters that are returned by the tasks in response to the queries may, in some examples, be dependent upon one or more algorithm-specific parameters that are used to configure the audio processing algorithms. The techniques of this disclosure may be used to reduce the amount of power consumed by a processor that is configured to execute one or more audio processing algorithms in an audio communication device, which may be particularly useful in audio communication devices where power resources are limited, such as, e.g., a mobile phone.

Abstract: A method and system for implementing a low complexity spectrum estimation technique for comfort noise generation are disclosed. Another aspect of the present invention involves segregating filter parameter encoding from an adaptation process for transmission in the form of silence insertion descriptors. A method for implementing a spectrum estimation for comfort noise generation comprises the steps of receiving an input noise signal; approximating a spectrum of the input noise signal using an algorithm over a period of time; detecting an absence of speech signals; and generating comfort noise based on the approximating step when the absence of speech signals is detected; wherein the spectrum of the input noise signal is substantially constant over the period of time.

Abstract: A method and system for determining filter gain and automatic gain control for fixed point low delay algorithms in real time systems are disclosed. An inventive aspect of the present invention involves computing filter gain using an approximation calculation by filtering a signal similar in spectrum to an input to be filtered and then fine-tuning it based at least in part on a short term moving mean square calculation in a low delay, low MIPS state of an algorithm. A method for determining a filter gain comprises the steps of: receiving an input to be filtered wherein the input has a spectrum; filtering a signal substantially similar in spectrum to the input to be filtered; computing the filter gain based on the filtering step; and fine tuning the filter gain.

Abstract: A method and system for implementing a simple Gaussian white noise generator for real time speech synthesis applications. According to an embodiment of the present invention, a method for generating a Gaussian random noise signal comprises the steps of: generating a first predetermined number of outputs from a first random number generator having a first period; generating a second predetermined number of outputs from a second random number generator having a second period different from the first period; calculating a first average from a first combination of inputs from the first random number generator and the second random number generator; calculating a second average from a second combination of inputs from the first random number generator and the second random number generator; and generating a Gaussian output based on the first average and the second average.

Abstract: A method and system for utilizing information content in speech and a transition hangover between speech and noise to generate comfort noise on the decoder side. This adaptation to noise may be accomplished using various algorithms of estimating the spectrum of color noise. According to an embodiment of the present invention, an adaptation algorithm may be implemented that adapts with time, rather than a block based algorithm to prevent the repeated generation of artifacts present in the block that are being adapting to. The method and system of the present invention generates comfort noise in the absence of silent insertion descriptions containing spectrum information thereby saving bandwidth and generating colored comfort noise that reflects the spectrum of the actual noise.

Abstract: The present invention is directed to a voice tone discriminator for distinguishing between call progress tones and voice. The voice tone discriminator is useful in various applications involving the ability to automatically charge a telephone user based on the exact time the user starts speaking. According to another aspect of the present invention, a prediction algorithm may be implemented for distinguishing voice and tone based on the fact that tones are more accurately modeled with a linear filter than voice signals. Thus, a low order filter or predictor may accurately model redundancies in tones but not in voice. A normalized error between an original and a predicted signal may be used to distinguish voice from tones. Voice may be detected when the error is above a preset threshold for a time greater than a preset fixed duration.