Encoding device, decoding device and program for triangle merge protection on boundary between two blocks

1. An encoding device that performs encoding on each of blocks obtained by dividing an image, the encoding device comprising:

a merge predictor circuitry configured to generate area prediction images of a plurality of divided areas obtained by dividing an encoding-target block and merge areas at boundaries of a plurality of the generated area prediction images through weighted averaging to generate a prediction block of the encoding-target block;

a transformer/quantizer circuitry configured to perform a transform process and a quantization process on a prediction residual that represents a difference between the encoding-target block and the prediction block;

an inverse quantizer/inverse transformer circuitry configured to restore the prediction residual by performing an inverse quantization process and an inverse transform process on transform coefficients obtained by the transformer/quantizer;

a combiner circuitry configured to combine the restored prediction residual and the prediction block to reconstruct the encoding-target block;

a deblocking filter circuitry configured to perform a filter process on a block boundary between two blocks including the reconstructed encoding-target block and an adjacent block adjacent to the encoding-target block; and

a filter controller circuitry configured to control the deblocking filter based on a position of a merged area merged by the merge predictor through the weighted averaging, wherein

the deblocking filter is configured to perform the filter process in units of two sub-blocks across the block boundary, and

the filter controller is configured to control the deblocking filter such that the filter process is performed on a sub-block boundary in response to the sub-block boundary between the two sub-blocks being adjacent to the merged area.

2. The encoding device according to claim 1 , wherein

when the sub-block boundary is not adjacent to the merged area, the filter controller is configured to control whether or not the filter process is performed on the sub-block boundary based on at least one of whether or not a non-zero transform coefficient exists in each of the two sub-blocks or information regarding motion vectors of the two sub-blocks.

3. A decoding device that performs decoding on each of blocks obtained by dividing an image, the decoding device comprising:

an entropy decoder circuitry configured to output transform coefficients corresponding to a decoding-target block by decoding an encoded stream;

an inverse quantizer/inverse transformer circuitry configured to restore a prediction residual by performing an inverse quantization process and an inverse transform process on the transform coefficients outputted by the entropy decoder;

a merge predictor circuitry configured to generate area prediction images of a plurality of divided areas obtained by dividing the decoding-target block and merge areas at boundaries of a plurality of the generated area prediction images through weighted averaging to generate a prediction block of the decoding-target block;

a combiner circuitry configured to combine the restored prediction residual and the prediction block to reconstruct the decoding-target block;

a deblocking filter circuitry configured to perform a filter process on a block boundary between two blocks including the reconstructed decoding-target block and an adjacent block adjacent to the decoding-target block; and

a filter controller circuitry configured to control the deblocking filter based on a position of a merged area merged by the merge predictor through the weighted averaging, wherein

the deblocking filter is configured to perform the filter process in units of two sub-blocks across the block boundary, and

the filter controller is configured to control the deblocking filter such that the filter process is performed on a sub-block boundary in response to the sub-block boundary between the two sub-blocks being adjacent to the merged area.

4. The decoding device according to claim 3 , wherein

when the sub-block boundary is not adjacent to the merged area, the filter controller is configured to control whether or not the filter process is performed on the sub-block boundary based on at least one of whether or not a non-zero transform coefficient exists in each of the two sub-blocks or information regarding motion vectors of the two sub-blocks.

5. A non-transitory computer readable storage medium storing a program causing a computer to function as the encoding device according to claim 1 .

6. A non-transitory computer readable storage medium storing a program causing a computer to function as the decoding device according to claim 3 .