Abstract:
A moving image coding apparatus is a moving image coding apparatus which codes a moving image, and includes a storage unit in which a plurality of reference pictures is stored; and a coding unit which codes a plurality of coding target pictures. The coding unit codes as a B picture a specific coding target picture among the plurality of coding target pictures by using a first reference picture list and a second reference picture list. The first reference picture list includes only one long-term reference picture ahead of the specific coding target picture among the plurality of reference pictures in a display order. The second reference picture list includes only one short-term reference picture ahead of the specific coding target picture among the plurality of reference pictures in the display order.
Abstract:
A video coding apparatus is a video coding apparatus which codes a coding target video based on a coding standard, and includes: a dividing unit which divides an image included in the coding target video into a plurality of control blocks; and a prediction image generating unit which divides each of the control blocks into a plurality of prediction blocks, and generates, for each of the prediction blocks, a prediction image using one of inter prediction and intra prediction, wherein the coding standard allows each of the control blocks to be divided into the prediction blocks such that the prediction blocks have different sizes, and the prediction image generating unit divides each of the control blocks into the prediction blocks such that the prediction blocks all have an identical size, rather than dividing each of the control blocks into the prediction blocks such that the prediction blocks have different sizes.
Abstract:
An image encoding apparatus which encodes an input image includes: an intra prediction unit which performs intra prediction on a per-sub-block basis. The intra prediction unit includes: a size determining unit which determines whether the size of a current sub-block is less than or equal to a predetermined size; a candidate determining unit which determines m intra prediction modes (where m is a natural number) as candidate prediction modes when the size of the current sub-block is determined to be less than or equal to the predetermined size, the m intra prediction modes being less than M intra prediction modes predefined independently of the block size (where M is a natural number greater than or equal to 2); and a prediction unit which selects one of the candidate prediction modes and performs intra prediction on the current sub-block using the selected intra prediction mode.
Abstract:
An image encoding method includes: selecting, for each processing block, one of intra prediction modes specified by a coding standard, and performing intra prediction according to the intra prediction mode, wherein the intra prediction modes include a lower-left reference mode in which a processing block located at lower left of a current processing block is referred to, the processing blocks include a first processing block and a second processing block located at upper right of the first processing block, the second processing block being equal in size to the first processing block, the coding standard defines that information on the second processing block is written into a bitstream after information on the first processing block, and in the intra prediction, (i) selection of the lower-left reference mode is prohibited and intra prediction is performed on the second processing block, and, (ii) intra prediction is performed on the first processing block.
Abstract:
In an exemplary embodiment, in order to avoid enlargement of a circuit scale to perform coding processing in real time, a block size of a PU (evaluation PU (Prediction Unit)) used to evaluate a merge mode is restricted and the number of evaluation target merge candidates is restricted. In the case where the evaluation PU has the block size in which a CU (Cording Unit) is divided, at least one merge candidate common to a merge candidate list of a PU (inclusion PU) having the block size including the evaluation PU and a merge candidate list of each of a plurality of evaluation PUs is selected as the evaluation target merge candidate from the merge candidate lists of the evaluation PUs. In performing cost evaluation processing for the evaluation PU, cost evaluation processing is simultaneously performed on the inclusion PU using a calculated prediction residual.
Abstract:
An image encoding method includes: selecting, for each processing block, one of intra prediction modes specified by a coding standard, and performing intra prediction according to the intra prediction mode, wherein the intra prediction modes include a lower-left reference mode in which a processing block located at lower left of a current processing block is referred to, the processing blocks include a first processing block and a second processing block located at upper right of the first processing block, the second processing block being equal in size to the first processing block, the coding standard defines that information on the second processing block is written into a bitstream after information on the first processing block, and in the intra prediction, (i) selection of the lower-left reference mode is prohibited and intra prediction is performed on the second processing block, and, (ii) intra prediction is performed on the first processing block.
Abstract:
A video coding apparatus is a video coding apparatus which codes a coding target video based on a coding standard, and includes: a dividing unit which divides an image included in the coding target video into a plurality of control blocks; and a prediction image generating unit which divides each of the control blocks into a plurality of prediction blocks, and generates, for each of the prediction blocks, a prediction image using one of inter prediction and intra prediction, wherein the coding standard allows each of the control blocks to be divided into the prediction blocks such that the prediction blocks have different sizes, and the prediction image generating unit divides each of the control blocks into the prediction blocks such that the prediction blocks all have an identical size, rather than dividing each of the control blocks into the prediction blocks such that the prediction blocks have different sizes.
Abstract:
An intra prediction unit is a device for performing intra predictions compliant with a specified picture coding standard, and comprises n prediction processing units that perform a parallel processing of the intra predictions, where n is an integer larger than one. Each of m prediction modes excluding at least, one prediction mode among a plurality of prediction modes defined in the specified picture coding standard is allocated to one of the n prediction processing units, where m is an integer larger than one. Each of the n prediction processing units performs an evaluation processing for the allocated one or more prediction modes to evaluate which prediction mode is to be selected among the m prediction modes.
Abstract:
Provided is an image coding method which obtains a picture, and codes the obtained picture. The image coding method generates a processing block, performs a first intra prediction that selects one intra prediction mode from a first set of candidates based on a component of a first signal contained in the processing block, performs a second intra prediction that selects one intra prediction mode from a second set of candidates based on a component of a second signal contained in the processing block. The first set of candidates includes a plurality of intra prediction modes, and the second set of candidates includes an intra prediction mode, having no dependency between the second intra prediction and the first intra prediction, of the plurality of intra prediction modes. The first intra prediction and the second intra prediction are performed in parallel.
Abstract:
A video coding apparatus including a dividing part that outputs the coding target picture divided for each coding unit (basic CU); a prediction processor that generates a prediction image by performing one of intra prediction and inter-screen prediction; a difference calculator that generates a difference image by calculating a difference between the generated prediction image and an image corresponding to the prediction image in the coding target picture; a residual coder that generates a residual coefficient by performing transform processing and quantization processing on the generated difference image; an integration unit that integrates a plurality of basic CUs included in an N×N-pixel region into one new CU, and a code string generator that generates a code string corresponding to the post-integration new CU by performing variable-length coding and arithmetic coding on coding information and the residual coefficient.