Provided are an encoding device using predictive coding in a screen and a method thereof, and a decoding device and a method thereof. The encoding device is capable of generating a prediction block of a current block according to one of methods for generating a plurality of predetermined prediction blocks, and outputting at least one of encoding information and differential blocks as bitstream by entropy encoding according to whether differential blocks are encoded or not.

A method of encoding an image in a merge mode, the method including determining motion information of a current prediction unit, and generating a prediction block using the motion information; generating a residual block using an original block and the prediction block, transforming the residual block to generating a transformed block, quantizing the transformed block using a quantization parameter to generate a quantized block, and scanning the quantized block to entropy-code the quantized block; and encoding the motion information using effective spatial and temporal merge candidates of the current prediction unit. In addition, a motion vector of the temporal merge candidate is a motion vector of a temporal merge candidate within a temporal merge candidate picture, and the quantization parameter is encoded using an average of two effective quantization parameters among a left quantization parameter, an upper quantization parameter and a previous quantization parameter of a current coding unit, also when the quantized block is larger than a predetermined size, the quantized block is divided into a plurality of subblocks to be scanned, and a scan pattern for scanning the plurality of subblocks is the same as a scan pattern for scanning quantized coefficients within each subblock. Further, a scanning scheme for scanning the quantized coefficients is determined according to an intra-prediction mode and a size of a transform unit.

A method of encoding an image in a merge mode, the method including determining motion information of a current prediction unit, and generating a prediction block using the motion information; generating a residual block using an original block and the prediction block, transforming the residual block to generating a transformed block, quantizing the transformed block using a quantization parameter to generate a quantized block, and scanning the quantized block to entropy-code the quantized block; and encoding the motion information using effective spatial and temporal merge candidates of the current prediction unit. In addition, a motion vector of the temporal merge candidate is a motion vector of a temporal merge candidate within a temporal merge candidate picture, and the quantization parameter is encoded using an average of two effective quantization parameters among a left quantization parameter, an upper quantization parameter and a previous quantization parameter of a current coding unit, also when the quantized block is larger than a predetermined size, the quantized block is divided into a plurality of subblocks to be scanned, and a scan pattern for scanning the plurality of subblocks is the same as a scan pattern for scanning quantized coefficients within each subblock. Further, a scanning scheme for scanning the quantized coefficients is determined according to an intra-prediction mode and a size of a transform unit.

A video coding device may encode a video signal using intra-block copy prediction. A first picture prediction unit of a first picture may be identified. A second picture may be coded and identified. The second picture may be temporally related to the first picture, and the second picture may include second picture prediction units. A second picture prediction unit that is collocated with the first picture prediction unit may be identified. Prediction information for the first picture prediction unit may be generated. The prediction information may be based on a block vector of the second picture prediction unit that is collocated with the first picture prediction unit.

A video coding device may encode a video signal using intra-block copy prediction. A first picture prediction unit of a first picture may be identified. A second picture may be coded and identified. The second picture may be temporally related to the first picture, and the second picture may include second picture prediction units. A second picture prediction unit that is collocated with the first picture prediction unit may be identified. Prediction information for the first picture prediction unit may be generated. The prediction information may be based on a block vector of the second picture prediction unit that is collocated with the first picture prediction unit.

A picture prediction method includes receiving a bitstream, parsing the bitstream to obtain a prediction mode of a current block, when the prediction mode of the current block is a combined intra and inter prediction mode, selecting an execution manner of a triangular prediction unit mode according to a preset policy, determining motion information of the current block according to the execution manner of the triangular prediction unit mode, performing a motion compensation process based on the motion information, to obtain an inter prediction sample, obtaining an intra prediction sample according to the prediction mode of the current block, and combining the inter prediction sample and the intra prediction sample to obtain a prediction picture of the current block.

The present disclosure provides a video data processing method. The method includes receiving a bitstream; decoding an index associated with a coding unit based on the bitstream, the index indicating a selection mode among at least four selection modes; determining four samples based on the index; determining two parameters based on the four samples; determining predicted samples of the coding unit based on the two parameters; and decoding the coding unit based on the predicted samples.

Methods and apparatus for image or video decoding in a video decoding system are disclosed. Input data associated with a current block coded with palette mode is received to parse a palette predictor run. A position of reused colors in a palette predictor table is computed according to the palette predictor run. A size of the palette predictor table is determined and compared with the position computed according to the palette predictor run to obtain a comparison result. The decoder applies palette decoding to the current block according to the comparison result. If the comparison result indicates the position computed according to the palette predictor run is not within the palette predictor table, the position is changed to a new position to indicate a corresponding reused color for the current block or a decoding process of palette predictor reuse flags is terminated.

An index, indicating a vector representing a spatial relationship between a block to be encoded and at least one block spatially at the periphery of the block to be encoded, is encoded in a case where an coding mode to encode the block to be encoded is a first coding mode, and an index, indicating a vector representing a spatial relationship between the block to be encoded and at least one block spatially at the periphery of the block to be encoded, and a vector correlated with a block within an image that is different from the image to be encoded, is encoded in a case where the coding mode to encode the block to be encoded is a second coding mode.

An index, indicating a vector representing a spatial relationship between a block to be encoded and at least one block spatially at the periphery of the block to be encoded, is encoded in a case where an coding mode to encode the block to be encoded is a first coding mode, and an index, indicating a vector representing a spatial relationship between the block to be encoded and at least one block spatially at the periphery of the block to be encoded, and a vector correlated with a block within an image that is different from the image to be encoded, is encoded in a case where the coding mode to encode the block to be encoded is a second coding mode.