摘要:
The method includes the following units: a coefficient number detecting unit (109) for detecting the number of coefficients which has a value other than 0 for each block according to the generated coefficient, a coefficient number storing unit (110) for storing the number of coefficients detected, a coefficient number coding unit (111) for selecting a table for variable length coding based on the numbers of coefficients in the coded blocks located on the periphery of a current block to be coded with reference to the selected table for variable length coding so as to perform variable length coding for the number of coefficients.
摘要:
In the coding method of the present invention, by adding an identification signal for indicating that there is no need to reorder coded pictures in the case where no picture coded by referring to a single or two pictures in the backward direction in display order is included in the sequence data, a restriction on pictures not to refer to any picture except the pictures that are positioned in the temporally forward direction is imposed and pictures are coded in the same order as the display order. Also, in the decoding method, only pictures that are positioned in the temporally forward direction are referred to according to the above-mentioned identification signal and these coded pictures are decoded in the same order as the display order.
摘要:
A variable length coding method is provided for coding coefficients in each block which are obtained by performing frequency transformation on picture data of a moving picture per block having a predetermined size, and includes: a coefficient scanning step of scanning the coefficients in the block in a predetermined order; and a coding step of coding the coefficients scanned in the coefficient scanning step into variable length codes in a predetermined order by switching a plurality of tables to be used for coding. Here, a direction of switching between the tables may be one-directional. Also, the coding may be non-arithmetic coding.
摘要:
A variable length coding method is provided for coding coefficients in each block which are obtained by performing frequency transformation on picture data of a moving picture per block having a predetermined size, and includes: a coefficient scanning step of scanning the coefficients in the block in a predetermined order; and a coding step of coding the coefficients scanned in the coefficient scanning step into variable length codes in a predetermined order by switching a plurality of tables to be used for coding. Here, a direction of switching between the tables may be one-directional. Also, the coding may be non-arithmetic coding.
摘要:
In a picture coding method for generating a coded signal corresponding to each picture by coding a plurality of coded signals, a switching picture which is capable of switching a plurality of coded signals and subsequent pictures of the switching picture can refer to only a group of pictures of the same time in the coded signals. More specifically, the case where picture numbers of an adjacent picture of an S picture and the S picture are not continuous is not considered as an error.
摘要:
When a block (MB22) of which motion vector is referred to in the direct mode contains a plurality of motion vectors, 2 motion vectors MV23 and MV24, which are used for inter picture prediction of a current picture (P23) to be coded, are determined by scaling a value obtained from averaging the plurality of motion vectors or selecting one of the plurality of the motion vectors.
摘要:
A motion vector coding unit 117 executes processing including a neighboring block specification step (S100) of specifying a neighboring block which is located in the neighborhood of a current block; a judgment step (Steps S102, S104) of judging whether or not the neighboring block has been coded using a motion vector of another block; a prediction step (S106, S108) of deriving a predictive motion vector of the current block using a motion vector calculated from the motion vector of the other block as a motion vector of the neighboring block; and a coding step (S110) of coding the motion vector of the current block using the predictive motion vector.
摘要:
A motion vector coding method and apparatus that improves efficiency of coding motion vectors when a current block is coded using a plurality of motion vectors. The apparatus includes a motion vector coding unit that codes a motion vector inputted from a motion vector detecting unit. A motion vector for each current block is coded based on a difference between the motion vector and a predicted vector obtained from motion vectors for previously coded neighboring blocks. The predicted vector is generated by one of the following processes: (A) the motion vectors which refer to the same picture are selected from among the motion vectors for the neighboring blocks so as to generate the predicted vector; (B) the motion vectors for the respective neighboring blocks are ordered in the predetermined order, and the motion vectors of the same order rank are selected from the ordered motion vectors so as to generate the predicted vector; and (C) the predicted vector for the second motion vector of the current block shall be the first motion vector, and if the second motion vector and the first motion vector refer to different pictures, the first motion vector is scaled according to the temporal distance between the pictures so as to generate the predicted vector.
摘要:
A moving picture coding apparatus includes a motion estimation unit (101) for performing motion estimation by fixing the one of two reference pictures as a reference picture indicated by an inputted default reference picture number DefRefNo and a variable length coding unit (107) for performing variable length coding on coded residual data ERes, a prediction type PredType, a reference picture number RefNo2 and motion vectors MV1, MV2 on a block-by-block basis, and outputting them as coded moving picture data Str.
摘要:
According to a picture coding method of the present invention, a coded picture identified by a picture number is stored, as a reference picture, into a storage unit; commands indicating correspondence between picture numbers and reference indices for designating reference pictures and coefficients used for generation of predictive images are generated; a reference picture being used when motion compensation is performed on a current block in a current picture to be coded is designated by a reference index; a predictive image is generated by performing linear prediction on a block being obtained by motion estimation within the designated reference picture, by use of a coefficient corresponding to the reference index; a coded image signal including a coded signal obtained by coding a prediction error being a difference between the current block in the current picture to be coded and the predictive image, the commands, the reference index and the coefficient is outputted. At that time, information indicating the maximum reference index value is coded and included into the coded image signal, and the commands indicating correspondence between at least one picture number and a plurality of reference indices are generated.