Abstract:
Provided is a video decoding apparatus including an encoding information obtainer configured to obtain, from a bitstream, reference layer size information, reference layer offset information, current layer size information, and current layer offset information, a scale ratio determiner configured to determine a scale ratio indicating a difference between a size of a reference area and a size of an expanded reference area, according to the size of the reference area which is determined from the reference layer size information and the reference layer offset information and the size of the expanded reference area which is determined from the current layer size information and the current layer offset information, and an up-sampling unit configured to determine the expanded reference area by up-sampling the reference area according to the reference layer offset information, the current layer offset information, and the scale ratio.
Abstract:
A probably update method used in context-based adaptive binary arithmetic coding (CABAC) is disclosed. The probably update method for binary arithmetic decoding obtains an autocorrelation value of each bin by using values of received bins, determines at least one scaling factor used to update a probability of a binary value based on the autocorrelation value, and updates a probability used in context-based adaptive binary arithmetic decoding by using the determined at least one scaling factor.
Abstract:
Disclosed are a video encoding method and apparatus and a video decoding method and apparatus. The method of encoding video includes: producing a first predicted coding unit of a current coding unit, which is to be encoded; determining whether the current coding unit comprises a portion located outside a boundary of a current picture; and producing a second predicted coding unit is produced by changing a value of pixels of the first predicted coding unit by using the pixels of the first predicted coding unit and neighboring pixels of the pixels when the current coding unit does not include a portion located outside a boundary of the current picture. Accordingly, a residual block that is the difference between the current encoding unit and the second predicted encoding unit, can be encoded, thereby improving video prediction efficiency.
Abstract:
A video encoding method including determining a phase shift between pixels of an enhancement layer image and a reference layer image, according to a scaling factor between the enhancement layer image and the reference layer image and a color format of the enhancement layer; selecting at least one filter coefficient set corresponding to the phase shift, from filter coefficient data including filter coefficient sets; generating an up-sampled reference layer image by extending a resolution of the reference layer image according to the scaling factor by performing interpolation filtering on the reference layer image by using the filter coefficient set; obtaining a prediction error between the up-sampled reference layer image and the enhancement layer image; generating an enhancement layer bitstream including the prediction error and a scalable codec; and generating a base layer bitstream by encoding the base layer images.
Abstract:
Provided are a method and apparatus for encoding a video signal and a method and apparatus for decoding a video signal. The method of encoding the video signal includes: determining an optimum scaling bit depth of the video signal in consideration of a maximum bit number of an intermediate value obtained during transformation of the video signal and a maximum bit precision of the video signal; scaling the video signal according to a local shift value corresponding to a difference between the determined optimum scaling bit depth and an original bit depth of the video signal; and transforming the scaled video signal.
Abstract:
A video encoding method and apparatus, and a video decoding method and apparatus for generating a reconstructed image having a minimized error between an original image and the reconstructed image. The video decoding method accompanied by a sample adaptive offset (SAO) adjustment, the method includes: obtaining 5 slice SAO parameters with respect to a current slice from a slice header of a received bitstream; obtaining luma SAO use information for a luma component of the current slice and chroma SAO use information for chroma components thereof from among the slice SAO parameters; determining whether to perform a SAO operation on the luma component of 10 the current slice based on the obtained luma SAO use information; and equally determining whether to perform the SAO adjustment on a first chroma component and a second chroma component of the current slice based on the obtained chroma SAO use information.
Abstract:
A video encoding method and apparatus, and a video decoding method and apparatus for generating a reconstructed image having a minimized error between an original image and the reconstructed image. The video decoding method accompanied by a sample adaptive offset (SAO) adjustment, the method includes: obtaining 5 slice SAO parameters with respect to a current slice from a slice header of a received bitstream; obtaining luma SAO use information for a luma component of the current slice and chroma SAO use information for chroma components thereof from among the slice SAO parameters; determining whether to perform a SAO operation on the luma component of 10 the current slice based on the obtained luma SAO use information; and equally determining whether to perform the SAO adjustment on a first chroma component and a second chroma component of the current slice based on the obtained chroma SAO use information.
Abstract:
Provided are a method and apparatus for interpolating an image. The method includes: selecting a first filter, from among a plurality of different filters, for interpolating between pixel values of integer pixel units, according to an interpolation location; and generating at least one pixel value of at least one fractional pixel unit by interpolating between the pixel values of the integer pixel units by using the selected first filter.
Abstract:
A method and apparatus for encoding and decoding a video are provided. The method of encoding the video includes: determining whether a unidirectional motion estimation mode and a bidirectional motion estimation mode are to be used based on a size of a current prediction unit to be encoded, performing the motion estimation and the motion compensation on the current prediction unit according to the determining of whether the unidirectional motion estimation mode and the bidirectional motion estimation mode are to be used, determining an optimum motion estimation mode of the current prediction unit based on an encoding cost of the current prediction unit obtained through the performing of the motion estimation and the motion compensation, and encoding information indicating the determined optimum motion estimation mode based on the size of the current prediction unit.
Abstract:
A video encoding method and apparatus and video decoding method and apparatus generate a restored image having a minimum error with respect to an original image based on offset merge information indicating whether offset parameters of a current block and at least one neighboring block from among blocks of video are identical.