Abstract: A method and apparatus of improving the compression efficiency of a motion vector by efficiently predicting a motion vector in an enhancement layer from a motion vector in a base layer in a video coding method using a multi-layer are provided.

Abstract: Disclosed are a method and an apparatus for realizing signal to noise ratio (SNR) scalability in a video stream server in order to transmit a video stream in a variable network environment. An apparatus for adapting a bitrate of a coded scalable bit-stream based on multi-layers to a variable network environment, comprising a bit-stream parsing unit to parse an input bit-stream, a pre-decoding condition determining unit to determine a target transmission bitrate according to the variable network environment, a pre-decoding unit to skip at least one frame among the frames included in the parsed bit-stream according to the determined target transmission bitrate, and a bit-stream transmission unit to transmit to a client device the bit-stream that has been restructured due to frame skipping.

Abstract: A method and apparatus for efficiently predecoding a hybrid bitstream generated by a plurality of coding schemes are provided. The method includes obtaining a first bit-rate for a boundary between the lower layer bitstream and the upper layer bitstream and a second bit-rate for a boundary between motion information and texture information of the upper layer bitstream from the input hybrid bitstream, determining the target bit-rate according to variable network circumstances, and when the target bit-rate is between the first and second bit-rates, skipping the motion information of the upper layer bitstream and truncating all bits of the texture information of the upper layer bitstream from the tail, except bits corresponding to the difference between the target bit-rate and the first bit-rate.

Abstract: An MPEG video decoding method and an MPEG video decoder are provided. The method includes determining whether to perform motion compensation on motion-vector-decoded data or not depending on a value of a decoded motion vector, determining whether to perform inverse discrete cosine transformation (IDCT) on motion-compensated data or not depending on values of decoded DCT coefficients, and generating a decoded image based on the results of the two determinations.

Abstract: A compiler allocates an unroll_group_number conferred based on a sequence in which a loop body is replicated by loop unrolling to each loop body during loop unrolling based on the optimized number of loop unrolling. The allocated unroll_group_number is added to each instruction included in each loop body. A priority of an instruction is adjusted based on the allocated unroll_group_number during instruction scheduling.

Abstract: An MPEG video decoding method and an MPEG video decoder are provided. The method includes determining whether to perform motion compensation on motion-vector-decoded data or not depending on a value of a decoded motion vector, determining whether to perform inverse discrete cosine transformation (IDCT) on motion-compensated data or not depending on values of decoded DCT coefficients, and generating a decoded image based on the results of the two determinations.

Abstract: Context-based adaptive arithmetic coding and decoding methods and apparatuses with improved coding efficiency and video coding and decoding methods and apparatuses using the same are provided. The method for performing context-based adaptive arithmetic coding on a given slice in an enhancement layer frame of a video signal having a multi-layered structure includes steps of resetting a context model for the given slice to a context model for a base layer slice at the same temporal position as the given slice, arithmetically coding a data symbol of the given slice using the reset context model, and updating the context model based on the value of the arithmetically coded data symbol.

Abstract: An efficient device for air purification occurring in the presence of activated carbon or its equivalent by decomposing adsorbed impurities, such as volatile organic compounds, on the carbon surface by radiofrequency energy in the microwave range. The device contains an activated carbon bed, or its equivalent, for adsorption of impurities and is regenerated in-place by with radiofrequency energy in the microwave range by usage of one or more slot antennas. An oxygen-free sweep gas removes the impurities. The device is housed in a microwave cavity designed to reflect the microwaves leaving the slot antennas into a center section containing the activated carbon bed.

Abstract: A garbage collection unit and a garbage collection method in an embedded environment are provided. In the method, a memory is divided into a young generation area including first and second areas and an old generation area including a predetermined number of blocks, the young generation area is divided into two areas, the garbage collection is performed alternately in the first and second areas of the young generation area, and the garbage collection in the old generation area is performed gradually in units of individual frames including a predetermined number of blocks. Accordingly, time delay due to garbage collection can be minimized, thereby guaranteeing a real-time operation.

Abstract: A color space scalable video coding and decoding method and an apparatus for the same are disclosed that can adjust color components or color depth according to the performance of a decoder side. The color space scalable video coding method includes generating transform coefficients by removing the temporal redundancy and spatial redundancy of input video frames, quantizing the transform coefficients, generating a bit stream by entropy coding the quantized transform coefficients, and generating a color space scalable bit stream that includes the bit stream and position information of luminance data in the bit stream.

Abstract: Deblocking filter used in a video encoder/decoder based on a multilayer. In deciding a deblocking filter strength when performing a deblocking filtering with respect to a boundary between a current block coded by an intra-BL mode and its neighboring block, it is determined whether the current block or the neighboring block has coefficients. The filter strength is decided as a first filter strength if it is determined that the current block or the neighboring block has the coefficients, and the filter strength is decided as a second filter strength if it is determined that the current block or the neighboring block does not have the coefficients. The first filter strength is greater than the second filter strength.

Abstract: A method and apparatus for encoding and decoding a video signal according to directional intra-residual prediction. The video encoding method of the present invention includes calculating first residual data by performing directional intra-prediction on a first block of a base layer with reference to a second block of the base layer, calculating second residual data by performing directional intra-prediction on a third block of an enhancement layer that corresponds to the first block of the base layer with reference to a fourth block of the enhancement layer that corresponds to the second block of the base layer, and encoding the third block according to the directional intra-residual prediction by obtaining third residual data that is a difference between the first residual data and the second residual data.

Abstract: A method and apparatus for encoding and decoding a video signal by extending an application of directional intra-prediction. When performing a directional intra-prediction during video data encoding, a second block in a frame is searched in order to predict information of a first block included in the video data from the second block existing in the same frame as the first block, a residual between information included in the searched second block and the information included in the first block is calculated, and the calculated residual is encoded. The second block exists in a position adjacent to the first block, and the first block refers to the second block in a third direction existing between a first direction and a second direction that are adjacent to each other for use in the directional intra-prediction.

Abstract: A dequantization method and an apparatus in which restored values for original values are obtained by dequantizing quantization level values generated when the original values are quantized. The dequantization method includes updating a histogram by accumulating histogram counts for the quantization level values, estimating a distribution function of the original values based on the histogram, and obtaining the restored values for the quantization level values from the distribution function.

Abstract: A method and apparatus effectively encode multiple layers using interlayer information in a multi-layered video codec. The method includes reading information concerning the low layer picture, calculating weighting factors using the information concerning the low layer picture, calculating a weighted sum of reference pictures for the current picture using the weighting factors and generating a predicted picture for the current picture, and encoding a difference between the current picture and the predicted picture.

Abstract: A method for reducing the amount of computations required for multilayer-based progressive fine granular scalability (PFGS) algorithm and a video coding method and apparatus employing the same method are provided. The video coding method supporting fine granular scalability (FGS) includes obtaining a predicted image for a current frame using a motion vector estimated at predetermined accuracy, quantizing a residual between the current frame and the predicted image, inversely quantizing the quantized residual, and generating a reconstructed image for the current frame, performing motion compensation on an FGS layer reference frame and a base layer reference frame using the estimated motion vector, calculating a residual between the motion-compensated FGS layer reference frame and the motion-compensated base layer reference frame, subtracting the reconstructed image for the current frame and the calculated residual from the current frame, and encoding the result of subtraction.

Abstract: Context-based adaptive arithmetic coding and decoding methods and apparatuses with improved coding efficiency and video coding and decoding methods and apparatuses using the same are provided. The method for performing context-based adaptive arithmetic coding on a given slice in an enhancement layer frame of a video signal having a multi-layered structure includes steps of resetting a context model for the given slice to a context model for a base layer slice at the same temporal position as the given slice, arithmetically coding a data symbol of the given slice using the reset context model, and updating the context model based on the value of the arithmetically coded data symbol.

Abstract: Entropy coding and decoding methods are provided which improve an overall coding efficiency by selectively applying context-based adaptive coding methods having different characteristics. An entropy coding method includes performing context-based adaptive variable length coding on a data symbol; performing context-based adaptive arithmetic coding on the data symbol; receiving information regarding a reference block where the coding efficiency of the context-based adaptive arithmetic coding is higher than that of the context-based adaptive variable length coding; and forming a slice which includes the reference block, and performing the context-based adaptive arithmetic coding on the blocks coded after the reference block.

Abstract: A method and apparatus for encoding and decoding macroblocks in an intra-base layer prediction mode by selectively applying intra-coding are provided. The method includes the steps of calculating a difference between an input frame and a base layer frame calculated from the input frame and obtaining residual signals, converting the residual signals using an intra-coding method, and generating an enhancement layer frame including the converted residual signals.

Abstract: Context-based adaptive arithmetic coding and decoding methods and apparatuses with improved coding efficiency using the same are provided. The context-based adaptive arithmetic coding method includes resetting a context model for the given slice to a context model for a slice coded temporally before the given slice, arithmetically encoding a data symbol of the given slice using the reset context model, and updating the context model using a value of the data symbol. The context-based adaptive arithmetic decoding method includes resetting a context model for the given slice to a context model coded temporally before the given slice, arithmetically decoding a bitstream corresponding to the given slice using the reset context model to generate a data symbol of the given slice, and updating the context model using a value of the data symbol.