摘要:
A method of assigning a priority for controlling a bit rate of a bitstream having a plurality of quality layers is provided. The method includes composing first quality layers for a reference picture, composing second quality layers for a current picture that is encoded with reference to the reference picture, and assigning a priority each of the first and second quality layers, wherein a low priority is assigned to a quality layer having a small influence on a video quality reduction of the current picture when the quality layer is truncated.
摘要:
Provided is a method of and apparatus for video encoding and decoding based on motion estimation. The method includes generating a motion vector by searching a reference picture using pixels of a current block, generating a prediction motion vector that is a prediction value of the motion vector by searching the reference picture using previously encoded pixels located adjacent to the current block, and encoding the current block based on the motion vector and the prediction motion vector. By accurately predicting the motion vector of the current block, the number of bits required for encoding the motion vector can be reduced, thereby improving the compression rate of video data.
摘要:
A method and apparatus for encoding a skip macroblock by dividing the skip macroblock into smaller skip sub blocks and using predictive motion vectors predicted from motion vectors of blocks adjacent to the skip sub blocks, and a method and apparatus for decoding the skip macroblock is provided. Accordingly, by adding predetermined binary information indicating whether the skip macroblock is divided to the skip macroblock that generally transmits only prediction mode information, division of the skip macroblock can be adaptively applied, or all skip macroblocks can be divided into sub-blocks to be processed, so that pixel values in the skip macroblock can be predicted by using motion vectors of spatially adjacent blocks. Therefore, prediction efficiency increases.
摘要:
A method of encoding flags, a method of decoding flags and an apparatus thereof, in which flag encoding and decoding can be efficiently performed by using spatial correlation between various flags included a plurality of blocks are provided. The method includes collecting flag values respectively allocated to groups of the plurality of blocks according to spatial correlation of blocks to create a flag bit-string, dividing the flag bit-string into a plurality of divided bit-strings using a group size, setting a pattern bit indicating whether all bits included in the divided bit-strings are 0 or not, and performing entropy coding on the divided bit-strings according to the set pattern bit.
摘要:
A method and apparatus for performing a motion prediction using an inverse motion transformation are provided. The method includes generating a second motion vector by inverse-transforming a first motion vector of a second block in a lower layer, the second block corresponding to a first block in a current layer; predicting a motion vector of the first block using the second motion vector; and encoding the first block using the predicted motion vector. The apparatus includes a motion vector inverse-transforming unit that generates a second motion vector by inverse-transforming a first motion vector of a second block in a lower layer corresponding to a first block in a current layer; a predicting unit that predicts a motion vector of the first block using the second motion vector; and an inter-prediction encoding unit that encodes the first block using the predicted motion vector.
摘要:
A video encoding/decoding method and apparatus in a temporal direct mode in a hierarchical structure. The video encoding method in the temporal direct mode in the hierarchical structure includes calculating a temporal position of a forward reference frame or a backward reference frame of a high-pass frame; searching for frames that exist at the temporal position and have motion vector information; if there is a plurality of frames searched for, selecting as a co-located frame a frame, among the plurality of frames, having a motion vector of which an interval is closest to a difference in interval between the forward reference frame and the backward reference frame of the high-pass frame, and extracting the motion vector of the selected frame; and encoding information on the selected frame so that the high-pass frame can use the extracted motion vector.
摘要:
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.
摘要:
A method and apparatus are provided for improving the compression efficiency of motion vectors of an unsynchronized picture by efficiently predicting the motion vectors using motion vectors of a lower layer. The method compresses motion vectors of an unsynchronized picture belonging to a current layer in a video encoder based on a multilayer having at least the current layer and a lower layer of the current layer. The method includes selecting a base picture for the unsynchronized picture, generating a predicted motion vector of the current layer from a motion vector of the base picture, subtracting the predicted motion vector from a motion vector of the unsynchronized picture, and encoding the result of subtraction.
摘要:
Video coding and decoding methods using interlayer filtering and a video encoder and decoder using the same are provided. Multi-layer video coding employing a plurality of video coding algorithms can improve video coding efficiency by using interlayer filtering. The video coding method includes encoding video frames using a first video coding scheme, performing interlayer filtering on the frames encoded by the first video coding scheme, encoding the video frames using a second video coding scheme by referring to the frames subjected to the interlayer filtering, and generating a bitstream containing the frames encoded by the first and second video coding schemes.
摘要:
A method and apparatus for encoding a skip macroblock by dividing the skip macroblock into smaller skip sub blocks and using predictive motion vectors predicted from motion vectors of blocks adjacent to the skip sub blocks, and a method and apparatus for decoding the skip macroblock is provided. Accordingly, by adding predetermined binary information indicating whether the skip macroblock is divided to the skip macroblock that generally transmits only prediction mode information, division of the skip macroblock can be adaptively applied, or all skip macroblocks can be divided into sub-blocks to be processed, so that pixel values in the skip macroblock can be predicted by using motion vectors of spatially adjacent blocks. Therefore, prediction efficiency increases.