Abstract: An apparatus for transcoding an audio signal between a CELP-based coder and a hybrid coder includes a source bitstream unwrapper configured to receive a source bitstream, extract one or more CELP compression parameters from the source bitstream, and construct an audio signal vector from the source bitstream while maintaining the one or more extracted CELP compression parameters. The apparatus also includes a frame interpolator coupled to the source bitstream unwrapper and a compression parameter converter coupled to frame interpolator. The compression parameter converter is configured to calculate output compression parameters from at least one of the interpolated compression parameters or the one or more extracted CELP compression parameters. Additionally, the apparatus includes a destination bitstream wrapper coupled to the compression parameter converter and a mapping parameter tuner coupled to the frame interpolator.

Abstract: A method for transcoding a CELP based compressed voice bitstream from source codec to destination codec. The method includes processing a source codec input CELP bitstream to unpack at least one or more CELP parameters from the input CELP bitstream and interpolating one or more of the plurality of unpacked CELP parameters from a source codec format to a destination codec format if a difference of one or more of a plurality of destination codec parameters including a frame size, a subframe size, and/or sampling rate of the destination codec format and one or more of a plurality of source codec parameters including a frame size, a subframe size, or sampling rate of the source codec format exist. The method includes encoding the one or more CELP parameters for the destination codec and processing a destination CELP bitstream by at least packing the one or more CELP parameters for the destination codec.

Abstract: A method of removing a motion vector from a group of motion vectors used in an encoding process includes providing a list of motion vectors, selecting an initial motion vector from the list of motion vectors, and providing an intermediate motion vector using a motion vector refinement process. The motion vector refinement process uses, in part, the initial motion vector. The method also includes forming a region defined by one or more parameters associated with the initial motion vector and one or more parameters associated with the intermediate motion vector, selecting an additional motion vector from the list of motion vectors, determining that the additional motion vector points into the region, and modifying a state of the additional motion vector.

Abstract: A conferencing system is provided that utilizes both time domain signal mixing and direct signal fast transcoding. An exemplary embodiment of the present invention utilizes both time domain signal mixing and direct signal fast transcoding to process a bit-stream from a same channel during a conference.

Abstract: A method for providing a multimedia service to a multimedia terminal includes establishing an audio link between the multimedia terminal and a server over an audio channel, and detecting one or more media capabilities of the multimedia terminal. The method also includes providing an application logic for the multimedia service, establishing a visual link between the multimedia terminal and the server over a video channel, providing an audio stream for the multimedia service over the audio link, and providing a visual stream for the multimedia service over the video link. The method further includes combining the video link and the audio link, and adjusting a transmission time of one or more packets in the visual stream to synchronize the visual stream with the audio stream.

Abstract: A method and apparatus for frame classification and rate determination in voice transcoders. The apparatus includes a classifier input parameter preparation module that unpacks the bitstream from the source codec and selects the codec parameters to be used for classification, parameter buffers that store previous input and output parameters of previous frames, and a frame classification and rate decision module that uses the source codec parameters from the current frame and zero or more frames to determine the frame class, rate, and classification feature parameters for the destination codec. The classifier input parameter preparation module separates the bitstream code and unquantizes the sub-codes into the codec parameters. The frame classification and rate decision module comprises M sub-classifiers and a final decision module.

Abstract: A variable-rate voice transcoder that transcodes a bitstream representing frames of data encoded according to a first compression standard to a bitstream representing frames of data according to a second compression standard; the second compression standard defines a variable-rate voice codec. The method includes unquantizing a bitstream into a first set of parameters compatible with the first compression standard. The first set of parameters in addition to external control commands are then used to determine a frame class and a rate for the second compression standard. Next, the first set of parameters are transformed into a second set of parameters compatible with the second compression standard according to the frame-classification and rate determination decision. Lastly, the second set of parameters is packed into a bitstream compatible with the second compression standard.

Abstract: A method and apparatus for a voice transcoder that converts a bitstream representing frames of data encoded according to a first voice compression standard to a bitstream representing frames of data according to a second voice compression standard using perceptual weighting that uses tuned weighting factors, such that the bitstream of a second voice compression standard to produce a higher quality decoded voice signal than a comparable tandem transcoding solution.

Abstract: A multimedia multi-service platform for providing one or more multimedia value added services in one or more telecommunications networks includes one or more application servers configured to operate in part according to a service program. The platform also includes one or more media servers configured to access, handle, process, and deliver media. The platform further includes one or more logic controllers and one or more management modules.

Abstract: A Field Programmable Gate Arrays (FPGA) design uses a Coordinate Rotation DIgital Computer (CORDIC) algorithm that can convert a Givens rotation of a vector to a set of shift-add operations. The CORDIC algorithm can be easily implemented in hardware architecture, therefore in FPGA. Since the computation of the inverse of the data correlation matrix involves a series of Givens rotations, the utility of the CORDIC algorithm allows a causal Constrained Energy Minimization (CEM) to perform real-time processing in FPGA. An FPGA implementation of the causal CEM is described and its detailed architecture is also described.

Abstract: An apparatus and method for mapping CELP parameters between a source codec and a destination codec. The apparatus includes an LSP mapping module, an adaptive codebook mapping module coupled to the LSP mapping module, and a fixed codebook mapping module coupled to the LSP mapping module and the adaptive codebook mapping module. The LSP mapping module includes an LP overflow module and an LSP parameter modification module. The adaptive codebook mapping module includes a first pitch gain codebook. The fixed codebook mapping module includes a first target processing module, a pulse search module, a fixed codebook gain estimation module, a pulse position searching module.

Abstract: The present invention relates to converting media bitstreams across different networks in a media gateway without any algorithmic delay, and reduces the computation load within the transmission in the situation where the bandwidth of the outgoing network varies dynamically. A first embodiment of the present invention provides an apparatus and a method for a Reduced-Algorithmic-Delay Media Stream Unit Conversion module which is a light weight Simple Pass-Through operation. A second embodiment of the present invention provides an apparatus and a method for a Reduced-Algorithmic-Delay Video Rate Conversion. An alternative embodiment provides an apparatus and a method for a Smart Pass-Through Operation which involves switching between the Simple Pass-Through and the Rate Converter. The methods and apparatuses provided by the first and second embodiment can be used as a stand alone system, or as part of the module of the alternative embodiment.

Abstract: A method for transcoding a CELP based compressed voice bitstream from source codec to destination codec. The method includes processing a source codec input CELP bitstream to unpack at least one or more CELP parameters from the input CELP bitstream and interpolating one or more of the plurality of unpacked CELP parameters from a source codec format to a destination codec format if a difference of one or more of a plurality of destination codec parameters including a frame size, a subframe size, and/or sampling rate of the destination codec format and one or more of a plurality of source codec parameters including a frame size, a subframe size, or sampling rate of the source codec format exist. The method includes encoding the one or more CELP parameters for the destination codec and processing a destination CELP bitstream by at least packing the one or more CELP parameters for the destination codec.

Abstract: A conferencing system is provided that utilizes both time domain signal mixing and direct signal fast transcoding. An exemplary embodiment of the present invention utilizes both time domain signal mixing and direct signal fast transcoding to process a bit-stream from a same channel during a conference.

Abstract: An apparatus for transcoding an audio signal between a CELP-based coder and a hybrid coder includes a source bitstream unwrapper configured to receive a source bitstream, extract one or more CELP compression parameters from the source bitstream, and construct an audio signal vector from the source bitstream while maintaining the one or more extracted CELP compression parameters. The apparatus also includes a frame interpolator coupled to the source bitstream unwrapper and a compression parameter converter coupled to frame interpolator. The compression parameter converter is configured to calculate output compression parameters from at least one of the interpolated compression parameters or the one or more extracted CELP compression parameters. Additionally, the apparatus includes a destination bitstream wrapper coupled to the compression parameter converter and a mapping parameter tuner coupled to the frame interpolator.

Abstract: An apparatus for use in video mixing of multiple video sources compressed in one or more video codecs includes a bitstream unpacker configured to receive and unpack each of the multiple video sources to provide intermediate video parameters including transform-domain coefficients, frame header information, macroblock header information, and motion vector data. The apparatus also includes an intermediate coefficient buffer coupled to the bitstream unpacker and a decision module coupled to the bitstream unpacker. The apparatus further includes a transform-domain coefficient downscaling module coupled to the intermediate coefficient buffer, a motion vector refinement module coupled to the bitstream unpacker, and a bitstream packer coupled to the decision module, the transform-domain coefficient downscaling module, and the motion vector refinement module.

Abstract: A method of removing a motion vector from a group of motion vectors used in an encoding process includes providing a list of motion vectors, selecting an initial motion vector from the list of motion vectors, and providing an intermediate motion vector using a motion vector refinement process. The motion vector refinement process uses, in part, the initial motion vector. The method also includes forming a region defined by one or more parameters associated with the initial motion vector and one or more parameters associated with the intermediate motion vector, selecting an additional motion vector from the list of motion vectors, determining that the additional motion vector points into the region, and modifying a state of the additional motion vector.

Abstract: A method and apparatus for a voice transcoder that converts a bitstream representing frames of data encoded according to a first voice compression standard to a bitstream representing frames of data according to a second voice compression standard using perceptual weighting that uses tuned weighting factors, such that the bitstream of a second voice compression standard to produce a higher quality decoded voice signal than a comparable tandem transcoding solution.

Abstract: An apparatus and method for encoding and decoding a voice signal. The apparatus includes an encoder configured to generate an output bitstream signal from an input voice signal. The output bitstream signal is associated with at least a first standard of a first plurality of CELP voice compression standards. Additionally, the apparatus includes a decoder configured to generate an output voice signal from an input bitstream signal. The input bitstream signal is associated with at least a first standard of a second plurality of CELP voice compression standards. The CELP encoder includes a plurality of codec-specific encoder modules. Additionally, the CELP encoder includes a plurality of generic encoder modules. The CELP decoder includes a plurality of codec-specific decoder modules. Additionally, the CELP decoder includes a plurality of generic decoder modules.

Abstract: An apparatus for processing CELP-based frames includes a first module for extracting a CELP parameter from a source codec, a second module coupled to the first module adapted to interpolate between a CELP parameter of the source codec and a destination codec, the CELP parameter being selected from a group consisting of a frame size, a subframe size, and a sampling rate, a third module coupled to the second module adapted to map the CELP parameter from the source codec to a CELP parameter of the destination codec, a fourth module coupled to the third module adapted to construct a destination output CELP frame based upon the CELP parameter from the destination codec, and a controller coupled the first, second, third and fourth modules, adapted to oversee an operation of the modules, adapted to receive instructions from an external application, and adapted to provide status information to the external application.