Abstract: Techniques, apparatus and systems for image decoding are described. A method performed by an image decoding apparatus includes generating motion compensation information and a quantized result of an error image that represents a difference between a current image to be decoded and a prediction image obtained by performing inter prediction on the current image from a bitstream of the current image. A reference image of the current image is received from an external memory unit based on the generated motion compensation information. The method includes restoring the current image based on the received reference image of the current image and the generated quantized result of the error image representing the difference between the current image and the prediction image. Receiving the reference image of the current image is performed while restoring a previous image, and restoring the current image is performed while receiving a reference image of a subsequent image.

Abstract: Techniques, apparatus and systems are described for performing variable length decoding. In one aspect, a variable length decoding apparatus includes a first computation unit to determine whether a symbol corresponding to an input data is included in an upper group or a lower group of a variable length code tree. Responsive to the determination, when the symbol corresponding to the input data is included in the lower group, the first computation unit detects look-up table information corresponding to a subgroup that includes the symbol corresponding to the input data within the lower group that includes multiple subgroups. The variable length decoding apparatus includes a second computation unit to detect the symbol corresponding to the input data by searching a look-up table corresponding to the look-up table information when the look-up table information is received from the first computation unit.

Abstract: Techniques, apparatus and computer readable storage media are described for encoding images in a video. In one aspect, a method performed by an encoding device to encode a video is described. The method includes sequentially performing a motion estimation operation and an encoding operation, which includes determining an operation mode of the motion estimation operation based on a quantity of calculations for the encoding operation. Sequentially performing a motion estimation operation and an encoding operation include performing the motion estimation operation with respect to an image of the video based on the determined operation mode. Additionally, sequentially performing a motion estimation operation and an encoding operation includes performing the encoding operation based on a result of the motion estimation operation.

Abstract: Techniques, apparatus and systems are described for performing variable length decoding. In one aspect, a variable length decoding apparatus includes a first computation unit to determine whether a symbol corresponding to an input data is included in an upper group or a lower group of a variable length code tree. Responsive to the determination, when the symbol corresponding to the input data is included in the lower group, the first computation unit detects look-up table information corresponding to a subgroup that includes the symbol corresponding to the input data within the lower group that includes multiple subgroups. The variable length decoding apparatus includes a second computation unit to detect the symbol corresponding to the input data by searching a look-up table corresponding to the look-up table information when the look-up table information is received from the first computation unit.

Abstract: Provided are a method and apparatus for sharing a memory of a multi-codec. For each of a plurality of codecs, the method and apparatus cluster a variable length code tree into a plurality of groups whereby a level difference between symbols in each group of the plurality of groups is less than a predetermined value, wherein the variable length code tree corresponds to at least one of variable length code tables for each of the plurality of codecs, refer to maximum levels of the symbols in each group of the plurality of groups, and determine a storage capacity of an internal memory shared between the variable length code tables for the plurality of codecs.

Abstract: Techniques, apparatus and systems for image decoding are described. A method performed by an image decoding apparatus includes generating motion compensation information and a quantized result of an error image that represents a difference between a current image to be decoded and a prediction image obtained by performing inter prediction on the current image from a bitstream of the current image. A reference image of the current image is received from an external memory unit based on the generated motion compensation information. The method includes restoring the current image based on the received reference image of the current image and the generated quantized result of the error image representing the difference between the current image and the prediction image. Receiving the reference image of the current image is performed while restoring a previous image, and restoring the current image is performed while receiving a reference image of a subsequent image.