Abstract: Provided are methods and apparatuses for coding a motion vector by a multimedia image codec. The method including: calculating and storing difference vectors which represent differences between adjacent motion vectors of image data; selecting a central axis of the stored difference vectors based on trend information of the difference vectors; transforming the difference vectors based on the central axis of the difference vectors; and performing bit coding using the axis-transformed difference vectors.

Abstract: A method and apparatus for estimating the contour of a user object in a moving picture during video communications so that a personal background image is not provided during video communications. Information about center coordinates as well as a size of a face of the user object is extracted from a moving picture frame. Edges are extracted from the moving picture frame, and a boundary of a head of the user object is estimated using a semicircle. The boundaries of left and right shoulders and left and right arms of the user object are estimated using second-order function graphs that overlap a largest portion of the edges. An entire contour of the user object is estimated according to the boundaries of the head, the left and right shoulders, and the left and right arms of the user object.

Abstract: A method and apparatus for decoding video data that is encoded by bit rate control to keep a bandwidth of a bit stream in a predetermined range are provided. The encoded video data is decoded, picture quality estimation information is estimated, the estimation including information about a bit stream size of a decoded video frame, the number of fragmented macro blocks included in the video frame, and the number of skip-mode macro blocks included in the video frame, the picture quality of the video data is determined based on a correlation between picture quality estimation information and SNR, and the video data is output by applying a picture quality improving algorithm to the video data, if the determined picture quality is lower than a predetermined level.

Abstract: A ring-shaped wireless input device for providing an indication of a scroll direction includes a housing having a ring shape, a wheel rotatably installed on the housing, a first sensor unit, that has first and second sections alternatively disposed along a circumference of the wheel and rotated along with the wheel, and a wireless communication unit which is fixedly disposed in the housing, and includes a second sensor unit arranged with the first sensor unit, the communication unit sending a scroll signal indicating an arranged state of the first sensor with regard to the second sensor to the host device.

Abstract: An apparatus for reproduction of an image frame in an image receiving system is disclosed. The apparatus includes a demultiplexer for restoring a received signal to a decodable bitstream and generating start information of each image frame of the bitstream, and an image decoder for decoding the bitstream restored by the demultiplexer, thereby generating a reproducible I frame or P frame, which is an image frame; an image reproduction time uniformity processing module for buffering each image frame output from the image decoder, and then outputting the buffered I frame or P frame while delaying the I frame or P frame based on the start information of each image frame provided by the demultiplexer according to a preset delay time. The present delay time has been preset to be greater than a processing time period required for decoding of an I frame and to be less than a time interval between image frames in the image bitstream.

Abstract: A method of performing an intra prediction coding with respect to a plurality of blocks included in an image frame is provided. The method of performing an intra prediction coding includes confirming whether a neighboring pixel that is referred to in an intra prediction of a block exists in the current frame, if the neighboring pixel referred to in the intra prediction exists, reading the color difference signal value of the pixel referred to in the intra prediction from the current image frame, if at least one neighboring pixel referred to in the intra prediction does not exist, reading the color difference signal value of at least one pixel from the previous image frame and performing the intra prediction with reference to the read color difference signal value of the pixel.

Abstract: Disclosed is an H.264 decoder equipped with multiple operation units, and a method for decoding compressed image data using same. The decoder comprises a plurality of operation units that successively perform a Variable Length Decoding (VLD) operation, an Inverse Transform & DeQuantization (ITDQ) operation, and an intra PREDiction & inter PREDiction (PRED) operation with respect to a macroblock for which each operation unit is to perform a decoding operation, on receiving information on a macroblock, for which each operation unit is to carry out the decoding operation, with reference to a synchronization information storage unit.

Abstract: A method and apparatus for error concealment in decoding of a moving picture. The method includes the steps of determining an erroneous macro block in a present frame when the moving picture is decoded, finding a first macro block having a highest similarity to the erroneous macro block and a second macro block having a next highest similarity to the erroneous block in a previous frame by comparing adjacent pixels of respective blocks in the previous frame with adjacent pixels of the erroneous block in the present frame; and replacing the erroneous block by using an average between the found macro blocks having the highest similarity and the second highest similarity to thereby conceal the erroneous macro block. The apparatus includes a parser, an entropy decoder, an inverse quantizer, an inverse converter, and a concealment unit that uses motion compensation from a previous frame to correct a macro block in a current frame.

Abstract: A method and apparatus for matching compressed video data under a wireless fading environment are disclosed. The apparatus includes an encoder for encoding and outputting the video data as a compressed bit stream, a channel error measurement unit for measuring Signal-to-Noise Ratio (SNR) or Carrier-to-Noise Ratio (CNR) of a wireless channel, and an encoder optimization module for determining if the current fading is slow fading or fast fading. A control signal is output to reduce a frame transmission ratio or to change the quality of the vide data if it is determined that the current fading is slow fading. Another control signal is output to adjust the size of a data output buffer of the wireless channel if it is determined that the current fading is fast fading.

Abstract: Disclosed is a method for interpolating chrominance signals in a video encoder and a decoder. The method includes the steps of accessing a memory unit to load an integer pixel value with regard to a plurality of motion compensation blocks, searching for a location of a motion vector s to perform sub-pixel interpolation of chrominance signals regarding the blocks and performing ¼ sub-pixel interpolation by row-based and column-based shifting when the motion vector indicates a ¼ location pixel with regard to the blocks. Also disclosed is an apparatus for performing the interpolating method described and a computer program product which when loaded into a computer system performs the interpolating method described.

Abstract: A deblocking filtering method for image data and a deblocking filter. According to the deblocking filtering method for image data and the deblocking filter, when computation of Boundary Strength (BS) values for each boundary based on one of horizontal and vertical directions from input image data is completed, it is possible to estimate BS values for each boundary based on a direction different from the currently selected direction by using the computed BS values. Further, deblocking filtering is performed based on corresponding directions according to the estimated values, so that the deblocking filtering can be completely performed with only a BS value of boundaries based on a selected one direction. Consequently, a BS value computation process necessarily required in a deblocking filtering process can be considerably reduced, and thus time required in the operation process of a deblocking filter can also be considerably reduced.

Abstract: A system and method for performing a handover of a mobile station (MS) by considering Quality of Service (QoS) in a broadband mobile communication system. The method can include the steps of: receiving information about one or more neighbor base stations and reception strengths for the neighbor base stations from a Serving Radio Access System (RAS) currently communicating with the MS; extracting a value of a specific field from the received information about the neighbor base stations; combining the extracted value of the specific field with the reception strengths to thereby obtain combined values, and selecting a maximum value among the combined values; and transmitting a handover (handoff) request message to a base station corresponding to the selected maximum value. The system includes an MS that analyzes information about neighbor stations received in a Mobile Neighbor Base-station Advertisement (MOB_NBR_ADV) message to select a target RAS.

Abstract: A Frame Rate Conversion (FRC) method using motion interpolation is disclosed. The FRC method includes checking the position of a motion vector intersecting an interpolated frame for each block of the interpolated frame, performing motion interpolation by acquiring a motion vector of each vertex of each block using motion vectors adjacent to each vertex, and performing motion interpolation on pixels of each block using the motion vector of each vertex.

Abstract: The present invention relates to a method and to an apparatus for encoding and decoding images by adaptively using an interpolation filter in consideration of the characteristics of input images. The apparatus of the present invention comprises a prediction block-generating unit including a selector for adaptively selecting an interpolation filter for generating a prediction block in consideration of the context information of an input image block, a filter bank in which groups of interpolation filters are stored in correspondence with the context information, and a specific interpolation filter which is selected from the filter bank in accordance with the control of the selector, and which interpolates a reference image block associated with the input image block.

Abstract: An image intra prediction method and image intra prediction apparatus and a decoding apparatus and a decoding method using the image intra prediction method are provided. The image intra prediction method includes: backing up boundary pixel values adjacent to a block that is to be decoded; correcting the boundary pixel values adjacent to the block that is to be decoded based on correlations between the boundary pixels and pixels adjacent to the boundary pixels; predicting a block that is to be decoded according to an intra mode, from among a plurality of intra modes, based on the corrected boundary pixel values; and restoring the boundary pixel values from the backed-up values.

Abstract: Provided are an image processing apparatus and an image processing method. The image processing method includes: obtaining a reference block a having a first resolution and a differential block having the first resolution; transforming a resolution of a prediction block having the first resolution and a resolution of the differential block having the first resolution in order to generate a prediction block having a second resolution and a differential block having the second resolution, the prediction block having the first resolution and the differential block having the first resolution being generated based on a pixel value of the reference block having the first resolution; and synthesizing the generated prediction block having the second resolution and the generated differential block having the second resolution in order to generate a target block having the second resolution.

Abstract: A method and apparatus for accessing a memory for processing moving pictures, which loads data from a frame buffer of an external memory, and uses a motion prediction technique. The method includes the steps of: loading, from the frame buffer, pixels of a relevant block of 8×8 size and extra pixel data necessary for an inter prediction while performing the inter prediction of a block of an 8×8 size following division of a macroblock, storing the pixels of the relevant block size of 8×8 and the extra pixel data in an internal cache memory. The stored pixels of the relevant block size of 8×8 and the stored extra pixel data are used; and then the stored pixels of the relevant block size of 8×8 and the stored extra pixel data stored in the cache memory are re-used during an inter prediction of the relevant block size of 8×8 and sub-blocks.

Abstract: A moving picture encoding/decoding apparatus and method for processing a moving picture, which is divided in units of slices are provided. The encoding method includes: dividing a moving picture in units of slices when the moving picture is received; determining an encoding order of moving pictures divided in units of slices; and generating a bitstream by encoding moving pictures, which are divided in units of slices, according to a corresponding order when the encoding order had been determined.

Abstract: A retransmission apparatus using an IP multicasting method for a DMB service including a plurality (n) of radio frequency (RF) receivers, each for receiving a DMB RF signal of a corresponding channel, a plurality (n) of DMB decoders, each for outputting a transport stream (TS) by decoding the DMB RF signal received from a corresponding RF receiver, a plurality (n) of slicers, each for processing the TS input from a corresponding DMB decoder; a plurality (n) of network interfacers, each for IP packetizing the TS sliced by a corresponding slicer; a network switch for receiving the IP packets from the plurality (n) of network interfacers, transferring the received IP packets to a multicasting processing unit, and receiving multicasting data from the multicasting processing unit, and the multicasting processing unit for receiving the IP packets from the network switch, creating a single piece of multicasting data by assigning multicasting addresses to the received IP packets, and outputting the created multicasti

Abstract: Disclosed is a method for depacketization of multimedia packet data, the method comprising: a context-aware step of parsing and recording a start code, which can identify each frame, in a first portion of a payload of a real-time transport protocol (RTP) packet; and a step of performing depacketization according to each packet by using the start code.