Image processing apparatus and image processing method
The present disclosure relates to an image processing apparatus and an image processing method that are capable of improving coding efficiency at the time when a prediction using a correlation within a screen is performed. A predicted vector generation section sets, at a time of encoding of a current motion vector of a current block for a prediction using a correlation within a screen, a candidate block to not available and generates a predicted vector of the current motion vector by using a reference motion vector, the reference motion vector being referred to when the predicted vector of the current motion vector is generated. A difference vector generation section generates a difference vector between the current motion vector and the predicted vector generated by the predicted vector generation section. The present disclosure can be applied to, for example, an encoding apparatus.
1. An image processing apparatus, comprising:
a predicted vector generation section configured to
exclude, at a time of encoding of a current motion vector of a current block for a prediction using a correlation within an image, in a case where a type of a reference picture of the current block and a type of a reference picture of a candidate block corresponding to a candidate of a reference motion vector are different from each other, the candidate block from candidates of the reference motion vector,
generate, in a case where a type of the reference picture of the current block and the type of the reference picture of the candidate block are each Short-Term Reference Picture (STRP), a predicted vector of the current motion vector by performing scaling on the reference motion vector,
generate, in a case where the type of the reference picture of the current block and the type of the reference picture of the candidate block are each Intra Block Copy (Intra BC), the predicted vector of the current motion vector by setting the reference motion vector to the predicted vector without scaling, and
generate, in a case where the type of the reference picture of the current block and the type of the reference picture of the candidate block are each Long-Term Reference Picture (LTRP), the predicted vector of the current motion vector by setting the reference motion vector to the predicted vector without scaling, the reference motion vector being referred to when the predicted vector of the current motion vector is generated;
a list creation section configured to register a picture of the current block in a predetermined position of a list of candidates of the reference picture of the current block, and rearrange order of the candidates of the reference picture in the list; and
a motion vector encoding section configured to encode the current motion vector using the predicted vector and the list,
wherein the predicted vector generation section, the motion vector encoding section, and the list creation section are each implemented via at least one processor.
2. The image processing apparatus according to claim 1 , further comprising:
a setting section configured to set the type of the reference picture of the current block to a long-term reference picture,
wherein the setting section is implemented via at least one processor.
3. The image processing apparatus according to claim 1 , wherein
the predicted vector generation section is further configured to determine that the type of the reference picture of the current block and the type of the reference picture of the candidate block are different from each other in a case where a picture of the candidate block and the reference picture of the candidate block are different from each other.
4. The image processing apparatus according to claim 1 , wherein the predetermined position is a head of the list of candidates.
5. The image processing apparatus according to claim 1 , wherein
the list creation section is further configured to rearrange the order of the candidates of the reference picture in the list, before registering the picture of the current block.
6. The image processing apparatus according to claim 1 , wherein
the list creation section is further configured to rearrange the order of the candidates of the reference picture other than the picture of the current block in the list, after registering the picture of the current block.
7. An image processing method for an image processing apparatus, the image processing method comprising:
excluding, at a time of encoding of a current motion vector of a current block for a prediction using a correlation within an image, in a case where a type of a reference picture of the current block and a type of a reference picture of a candidate block corresponding to a candidate of a reference motion vector are different from each other, the candidate block from candidates of the reference motion vector,
generating, in a case where a type of the reference picture of the current block and the type of the reference picture of the candidate block are each Short-Term Reference Picture (STRP), a predicted vector of the current motion vector by performing scaling on the reference motion vector;
generating, in a case where the type of the reference picture of the current block and the type of the reference picture of the candidate block are each Intra Block Copy (Intra BC), the predicted vector of the current motion vector by setting the reference motion vector to the predicted vector without scaling;
generating, in a case where the type of the reference picture of the current block and the type of the reference picture of the candidate block are each Long-Term Reference Picture (LTRP), the predicted vector of the current motion vector by setting the reference motion vector to the predicted vector without scaling, the reference motion vector being referred to when the predicted vector of the current motion vector is generated;
registering a picture of the current block in a predetermined position of a list of candidates of the reference picture of the current block;
rearranging order of the candidates of the reference picture in the list; and
encoding the current motion vector using the predicted vector and the list.
8. The image processing apparatus according to claim 1 , wherein in the case where the type of the reference picture of the current block and the type of the reference picture of the candidate block are identical with each other, the type of the reference picture of the current block and the type of the reference picture of the candidate block are both a short-term reference picture.
9. The image processing apparatus according to claim 1 , wherein the scaling of the reference motion vector is based on a difference in Picture Order Count (POC) between the reference picture of the current block and the reference picture of the candidate block.
10. The image processing apparatus according to claim 4 , wherein the list creation section is further configured to rearrange the order of the candidates of the reference picture in the list from the head of the list of candidates.