Abstract: A method of providing a quality measure for an output voice signal generated to reproduce an input voice signal, the method comprising: partitioning the input and output signals into frames; for each frame of the input signal, determining a disturbance relative to each of a plurality of frames of the output signal; determining a subset of the determined disturbances comprising one disturbance for each input frame such that a sum of the disturbances in the subset set is a minimum; and using the set of disturbances to provide the measure of quality.

Abstract: A method is provided for discarding an audio message if the audio message meets a predefined discarding condition, which may factor in at least the audio message's total length, presence of spoken word(s) in the audio message, presence of tone(s) in the audio message and the presence of click(s) in the audio message. An audio message may be discarded if no spoken words are detected in it and the audio message's total length is shorter than a predefined minimal message length, or it contains a tone and the audio message's total length minus the tone's length is shorter than the predefined minimal message length, or it contains a click sound and the audio message's total length minus the click's length is shorter than the predefined minimal message length. An audio message may be first stored in a memory buffer and then moved to a legitimate messages pool memory or to a spurious messages pool memory.

Abstract: A method of determining if an echo canceller comprised in a communication channel that is used to transmit at least one tonal signal and characterized by a model echo path of the channel, is acceptably adapted to cancel echoes in the channel, the method comprising: determining a performance measure how well the canceller cancels echoes of at least one test signal characterized by at least one frequency different from a frequency of the at least one tonal signal; and determining if the canceller is acceptably adapted responsive to the measure.

Abstract: Signal-type dependent real-time fax Relay.

Abstract: Disclosed is a method and circuit for echo suppression or cancellation. According to some embodiments of the present invention, there is provided a circuit including a Noise-Enhanced-Receiving-Direction unit and Narrow-Band Remover unit or units.

Abstract: As part of a system and method for transmitting a signaling tone over a packet switched data (or other communication) network, an audio encoder may have a speech encoding unit and a tone distorter. The tone distorter may distort one or more components of a signaling tone within an audio signal and the speech encoding unit may encode speech and the distorted signaling tone within the audio signal. A control signal may be sent to a tone generator to reproduce the distorted tone.

Abstract: A system, method and apparatus for communication is provided which includes maintaining a primary and a secondary network media devices at substantially similar encryption state, wherein the secondary network media device is a redundant network media device. Similar encryption state may be maintained by copying reception and transmission switchover parameters from the primary network media device to the redundant network media device, at least once per 2X packets, and preferably every 213 packets that are either transmitted by, or received at, the primary network media device. The redundant network media device may receive packets by utilizing copied reception switchover parameters and transmit packets by estimating transmission switchover parameters based on copied transmission switchover parameters. The reception and transmission switchover parameters may be associated with Secure Real-time Transport Protocol or with PacketCable protocol.

Abstract: A method of determining noise in an audio stream, the method comprising: acquiring a plurality of consecutive time frames of the audio stream each comprising samples of the audio stream; generating a discrete frequency spectrum for each frame responsive to the frame samples; partitioning the frequency spectrum of each frame into a plurality of same frequency bands; determining an audio energy for each frequency band in each frame; and determining an estimate of noise energy for each frequency band in a temporally last time frame responsive to a relatively small number of smallest values for the audio energy in the frequency band of the plurality of time frames.

Abstract: Gateway, method, and apparatus for communicating fax data over the Internet.

Abstract: A method for using a waveform segment in place of a missing portion of an audio waveform generated in response to a packet stream encoding portions of the audio waveform, the method comprising: phase matching a trailing portion of the waveform segment with a trailing portion of the audio waveform that follows the missing portion; and adding the phase matched waveform segment to the audio waveform.

Abstract: Disclosed is an echo suppresser or cancellation circuit including a speech signal extrapolation unit. The speech extrapolation unit may provide extrapolated signal segment approximations to an echo segment replacement unit. The echo segment replacement unit may replace a segment of a first speech signal suspected of being corrupted with an echo component of a second signal using the extrapolated signal segment approximated to represent the corrupted signal segment.

Abstract: A communication system comprising: at least one first communication device configured to communicate in half duplex mode using a first encoding-decoding format; at least one second communication device configured to communicate in half duplex mode using a second encoding-decoding format; a third communication device configured to communicate in half duplex mode using the first format; a fourth communication device configured to communicate in half duplex mode using the second format; wherein the third and fourth communication devices are configured to communicate with each other in half duplex mode using a third encoding decoding format.

Abstract: A method of providing a quality measure for an output voice signal generated to reproduce an input voice signal, the method comprising: partitioning the input and output signals into frames; for each frame of the input signal, determining a disturbance relative to each of a plurality of frames of the output signal; determining a subset of the determined disturbances comprising one disturbance for each input frame such that a sum of the disturbances in the subset set is a minimum; and using the set of disturbances to provide the measure of quality.

Abstract: In order to enable V.34 fax relay communications over IP (“FoIP”) without increasing a gateway complexity, the gateway relays all types of fax control signals in demodulated form and transfers fax image type signals either as demodulated or as PCM encoded signal, based on a predetermined condition. The PCM data type is added to FoIP protocol to allow transferring PCM encoded fax image signals without exiting from FoIP mode of operation until the completion of a fax call. During a FoIP call, the communicating gateway determines whether the input fax signal is a ‘fax control signal’ or a ‘fax image’ type signal. If the gateway determines that the input signal is a fax control signal or supported fax image signal, it handles it in a traditional fax relay manner. However, if the gateway determines that the input fax image type signal cannot be demodulated, it outputs the fax signal to the IP network as PCM encoded signal and without performing demodulation.

Abstract: A voice encoder which utilizes future data, such as the lookahead data typically available for linear predictive coding (LPC), to partially encode a future packet and to send the partial encoding as part of the current packet. A decoder utilizes the partial encoding of the previous packet to decode the current packet if the latter did not arrive properly.

Abstract: Disclosed is an echo suppresser or cancellation circuit including a speech signal extrapolation unit. The speech extrapolation unit may provide extrapolated signal segment approximations to an echo segment replacement unit. The echo segment replacement unit may replace a segment of a first speech signal suspected of being corrupted with an echo component of a second signal using the extrapolated signal segment approximated to represent the corrupted signal segment.

Abstract: A method is provided for discarding an audio message if the audio message meets a predefined discarding condition, which may factor in at least the audio message's total length, presence of spoken word(s) in the audio message, presence of tone(s) in the audio message and the presence of click(s) in the audio message. An audio message may be discarded if no spoken words are detected in it and the audio message's total length is shorter than a predefined minimal message length, or it contains a tone and the audio message's total length minus the tone's length is shorter than the predefined minimal message length, or it contains a click sound and the audio message's total length minus the click's length is shorter than the predefined minimal message length. An audio message may be first stored in a memory buffer and then moved to a legitimate messages pool memory or to a spurious messages pool memory.

Abstract: A method apparatus and system are provided for detecting pulses in a received signal wherein the spacing between the pulses may alternate in an expected manner. Generally, the method exploits intrinsic characteristics in the ensemble pulses, by performing correlation between pulses in a data stream representative of the received signal. Pulses may be related to an ensemble of pulses if their correlation result complies with a predefined criteria and the spacing between the correlated pulses is substantially the expected spacing. The correlation may be performed between two successive pulses, or it may be performed between non-successive pulses. The pulses may be alternating “start” and “stop” pulses of telephonic dial (rotary) pulses, and the expected spacing between the pulses may alternate between two values, “break” period and “make” period. Pulses may be correlated if their energy exceeds a predefined threshold value.

Abstract: A system, method and apparatus for communication is provided which includes maintaining a primary and a secondary network media devices at substantially similar encryption state, wherein the secondary network media device is a redundant network media device. Similar encryption state may be maintained by copying reception and transmission switchover parameters from the primary network media device to the redundant network media device, at least once per 2X packets, and preferably every 213 packets that are either transmitted by, or received at, the primary network media device. The redundant network media device may receive packets by utilizing copied reception switchover parameters and transmit packets by estimating transmission switchover parameters based on copied transmission switchover parameters. The reception and transmission switchover parameters may be associated with Secure Real-time Transport Protocol or with PacketCable protocol.

Abstract: A fax transmission method is provided for transmitting fax related data over packet switched network. The may include using a first streaming protocol to encapsulate a fax data set, and further encapsulating the fax packet using a second streaming protocol. The method may also include receiving a packet and de-encapsulating it by using the second streaming protocol to obtain a fax packet, and further de-encapsulating the fax packet using a second streaming protocol, to obtain a fax data set. An apparatus is also provided for transmitting fax related data over packet switched network, which utilizes the fax transmission method. The apparatus may be a network gateway, an Internet Aware mobile phone, Internet Aware fax or Internet Aware modem.