Abstract: A video encoding/decoding apparatus includes an encoding unit which processes video data to be transmitted in unit of slice, a multiplexer/demultiplexer which multiplexes the video data from the encoding unit and de-multiplexes video data received through a communication channel, a decoding unit which processes video data from the multiplexer/demultiplexer in unit of slice. The video information delay is reduced less than or equal to the audio information delay such that there is no need for additional memory to delay the audio information so as to synchronize with the video information.

Abstract: An apparatus and method for synchronizing the transmission of uplink signals and reception of downlink signals by a terminal in a mobile communication system is disclosed, the apparatus and method allowing a terminal to adaptively compensate for deflection generated in synchronization of a transmission channel and a fine adjustment to be made for controlling channel synchronization. A new switching point between uplink time slots and downlink time slots is determined based on a detected present switching point and a recognized uplink and downlink time slot construction, with the new switching point utilized to perform switching between a receiver and transmitter with a variable time interval. A delay may be inserted in a transmitted uplink signal to compensate for errors in the switching function.

Abstract: An apparatus and method for synchronizing the transmission of uplink signals and reception of downlink signals by a terminal in a mobile communication system is disclosed, the apparatus and method allowing the terminal itself to adaptively compensate for deflection generated in synchronization of the transmission channel and to recover a synchronization error of the transmission channel without re-setting communications with the base station. A feedback path is formed between a transmitting unit, a receiving unit and a processing unit to facilitate frequently checking the synchronization between uplink and downlink timeslots by generating a reference signal input to the transmitting unit and comparing a signal received from the receiving unit. The channel synchronization apparatus and method may be adapted for a terminal using a software-based modem or a hardware-based modem.

Abstract: A video data resending apparatus and method is disclosed. The present invention is capable of performing a selective resending process with respect to a local bit error of a previously sent video data packet, using a CONTRAXPAND™ buffer. The present invention has the effect of overcoming a time delay and overcoming sending suspension due to the resending of the video data. Also, the present invention can accurately block a distortion propagation to the adjacent video due to the local bit error.

Abstract: An apparatus and method for synchronizing the transmission of uplink signals and reception of downlink signals by a terminal in a mobile communication system is disclosed, the apparatus and method allowing the terminal itself to adaptively compensate for deflection generated in synchronization of the transmission channel and to recover a synchronization error of the transmission channel without re-setting communications with the base station. A feedback path is formed between a transmitting unit, a receiving unit and a processing unit to facilitate frequently checking the synchronization between uplink and downlink timeslots by generating a reference signal input to the transmitting unit and comparing a signal received from the receiving unit. The channel synchronization apparatus and method may be adapted for a terminal using a software-based modem or a hardware-based modem.

Abstract: An apparatus and method for synchronizing the transmission of uplink signals and reception of downlink signals by a terminal in a mobile communication system is disclosed, the apparatus and method allowing a terminal to adaptively compensate for deflection generated in synchronization of a transmission channel and a fine adjustment to be made for controlling channel synchronization. A new switching point between uplink time slots and downlink time slots is determined based on a detected present switching point and a recognized uplink and downlink time slot construction, with the new switching point utilized to perform switching between a receiver and transmitter with a variable time interval. A delay may be inserted in a transmitted uplink signal to compensate for errors in the switching function.

Abstract: A video encoding/decoding apparatus includes an encoding unit which processes video data to be transmitted in unit of slice, a multiplexer/demultiplexer which multiplexes the video data from the encoding unit and de-multiplexes video data received through a communication channel, a decoding unit which processes video data from the multiplexer/demultiplexer in unit of slice. The video information delay is reduced less than or equal to the audio information delay such that there is no need for additional memory to delay the audio information so as to synchronize with the video information.

Abstract: A method of buffering video data in a video compression system, in which a video bit stream, compressed on the basis of an international standard, is transmitted adaptively to a state of a transmission channel under a digital communication environment where a transmission speed is very low and a bit error generation rate is very high. The video data buffering method comprises the step of performing a discrete orthogonal transform operation with respect to input video data in the unit of blocks and storing the resultant coefficients in the unit of discrete orthogonal transform components.

Abstract: Video rate control and buffering based on a rate estimator and scene change features has been investigated for constant bit rate channels. A scene change-based, predictive technique has been applied so that the buffer occupancy may be controlled effectively in advance of encountering a dramatic variation in the video rate. The current occupancy and the future occupancy, has been used to control the quantization step size to provide substantial improvements in the video rate control. A non-linear rate estimator based on the RBF network which has better performance in terms of the buffer occupancy is also provided.

Abstract: Fuzzy rule-based control is applied to video rate control in the present invention. A basic fuzzy logic controlling apparatus using the occupancy as a fuzzy control variable is provided. Other fuzzy logic controlling apparatus is also provided: the video quality-controlled, the scene change based and the quality-monitored. The occupancy-based controlling apparatus is adopted to form a backbone scheme. The accumulative quality measure and the scene change features are then introduced to improve the video quality. The quality-monitored FRC(FRC-QM), which is controlled by both the quality factor and the scene change-based factor, is superior to the other schemes in respect of both the occupancy and the quality.

Abstract: Fuzzy rule-based control is applied to video rate control in the present invention. A basic fuzzy logic controlling apparatus using the occupancy as a fuzzy control variable is provided. Other fuzzy logic controlling apparatus is also provided: the video quality-controlled, the scene change based and the quality-monitored. The occupancy-based controlling apparatus is adopted to form a backbone scheme. The accumulative quality measure and the scene change features are then introduced to improve the video quality. The quality-monitored FRC (FRC-QM), which is controlled by both the quality factor and the scene change-based factor, is superior to the other schemes in respect of both the occupancy and the quality.