Abstract:
An Internet Set-Top Box (ISTB) and a method of providing wideband IP telephony services using the ISTB are provided, which are capable of implementing wideband voice communication services using a wideband voice codec, controlling a Real-Time Transport Protocol (RTP) packet payload to process a variety of wideband speech frame payloads, and providing high-quality wideband IP telephony services by controlling a jitter buffer to maintain conference call synchronization.
Abstract:
An encoding apparatus and a decoding apparatus for reducing the quantization error of a G.711 codec and improving sound quality are provided. The encoding apparatus includes a G.711 encoder which generates a G.711 bitstream by encoding an input audio signal; an enhancement-layer encoder which chooses one of a static bit allocation method and a dynamic bit allocation method that can produce less quantization error based on the input audio signal and the G.711 bitstream, and outputs an enhancement-layer bitstream including encoded additional mantissa information obtained by using the chosen bit allocation method; and a multiplexer which multiplexes the G.711 bitstream and the enhancement-layer bitstream. Therefore, it is possible to reduce the quantization error of a G.711 codec and improve sound quality.
Abstract:
Provided are a method and an apparatus for encoding and decoding an audio signal. A method for encoding an audio signal includes receiving a transformed audio signal, dividing the transformed audio signal into a plurality of subbands, performing a first sinusoidal pulse coding operation on the subbands, determining a performance region of a second sinusoidal pulse coding operation among the subbands on the basis of coding information of the first sinusoidal pulse coding operation, and performing the second sinusoidal pulse coding operation on the determined performance region, wherein the first sinusoidal pulse coding operation is performed variably according to the coding information. Accordingly, it is possible to further improve the quality of a synthesized signal by considering the sinusoidal pulse coding of a lower layer when encoding or decoding an audio signal in an upper layer by a layered sinusoidal pulse coding scheme.
Abstract:
An encoding apparatus and a decoding apparatus for reducing the quantization error of a G.711 codec and improving sound quality are provided. The encoding apparatus includes a G.711 encoder which generates a G.711 bitstream by encoding an input audio signal; an enhancement-layer encoder which chooses one of a static bit allocation method and a dynamic bit allocation method that can produce less quantization error based on the input audio signal and the G.711 bitstream, and outputs an enhancement-layer bitstream including encoded additional mantissa information obtained by using the chosen bit allocation method; and a multiplexer which multiplexes the G.711 bitstream and the enhancement-layer bitstream. Therefore, it is possible to reduce the quantization error of a G.711 codec and improve sound quality.
Abstract:
The transmission delay of a voice frame can be reduced by performing internal collision resolution and frame aggregation according to the presence or absence of a voice frame awaiting transmission in a MAC layer, thereby reducing an end-to-end voice transmission delay time for a VoIP service.
Abstract:
Disclosed is a method and apparatus for realizing an effective service adaptation in consideration of delay factors possibly generated in combining (or compositing) already existing Web services in constituting a composite Web service. A failure or delay in executing a Web service is predicted in consideration of features (or factors) of QoS of Web services constituting a composite Web service, and a substitute Web service is executed or a speculative execution is performed to thus stably and quickly constitute a composite Web service.
Abstract:
A signal processing technology achieved in a signal processing module, which is physically separate from a control module for controlling overall operations of a signal processing apparatus, is provided. Input of new data to a system memory is recognized. Upon the recognition of the input of the new data, the new data is read from the system memory. The new data read from the system memory is written to a local memory. Data sharing between software and hardware is effectively achieved in a system for performing a wideband codec processing using a dedicated hardware.
Abstract:
A codec platform apparatus which can perform encoding or decoding regardless of a sampling frequency supported by a codec platform is provided. The codec platform apparatus includes an analog-to-digital converter (ADC) converting an analog input signal into a digital signal by sampling the analog input signal at a codec platform sampling frequency; a sampling frequency converter converting the digital signal provided by the ADC into a digital signal having a codec sampling frequency; and an encoder generating a bit stream by compressing the digital signal provided by the sampling frequency converter. Since there is no need to adopt a new codec platform even when an existing codec platform does not support the sampling frequency of a new codec, there is no need to implant the new codec. Therefore, it is possible to improve user satisfaction.
Abstract:
Provided are a method and an apparatus for decoding an audio signal. A method for decoding an audio signal encoded by a layered sinusoidal pulse coding scheme using one or more sinusoidal pulses includes decoding the encoded audio signal, setting a smoothing frequency band of the decoded audio signal according to a layer structure of the layered sinusoidal pulse coding scheme, dividing the smoothing frequency band into one or more subbands, and smoothing the decoded audio signal on a subband-by-subband basis. Accordingly, a decoding operation time can be reduced and the quality of a synthesized signal can be improved by variably setting a frequency band to be smoothed, when decoding an audio signal encoded by a layered sinusoidal pulse coding scheme using one or more sinusoidal pulses.
Abstract:
A service goal interpreting apparatus for goal-driven semantic service discovery is provided. The service goal interpreting apparatus includes a goal interpretation unit that interprets a goal of at least one service or application provided on the Web, and a goal registration unit that registers the goal interpreted by the goal interpretation unit in a service registry.