Video image encoding and decoding method, apparatus, and device

A video image encoding method, comprising:

• determining a size of an affine motion compensation image sub-block in an affine image block based on a motion vector difference of the affine image block, a motion vector precision of the affine image block, a distance between control points in the affine image block, and a size of the affine image block, so that a length of the affine image block in a horizontal direction is an integer multiple of a length of the affine motion compensation image sub-block in the horizontal direction, and a length of the affine image block in a vertical direction is an integer multiple of a length of the affine motion compensation image sub-block in the vertical direction;
• and the control points each have a motion vector for determining the motion vector difference;
• and
• performing encoding processing on the affine image block based on the size of the affine motion compensation image sub-block.

A video image decoding apparatus, comprising:

• an image sub-block size determining module, configured to determine a size of an affine motion compensation image sub-block in an affine image block based on the motion vector difference of the affine image block, the motion vector precision of the affine image block, a distance between control points in the affine image block, and a size of the affine image block, so that a length of the affine image block in a horizontal direction is an integer multiple of a length of the affine motion compensation image sub-block in the horizontal direction, and a length of the affine image block in a vertical direction is an integer multiple of a length of the affine motion compensation image sub-block in the vertical direction;
• and the control points each has a motion vector for determining the motion vector difference;
• and
• a decoding module, configured to perform decoding processing on the affine image block based on the size of the affine motion compensation image sub-block.

A video image encoding apparatus, comprising:

• an image sub-block size determining module, configured to determine a size of an affine motion compensation image sub-block in an affine image block based on a motion vector difference, a motion vector precision of the affine image block, a distance between control points of the affine image block in the affine image block, and a size of the affine image block, so that a length of the affine image block in a horizontal direction is an integer multiple of a length of the affine motion compensation image sub-block in the horizontal direction, and a length of the affine image block in a vertical direction is an integer multiple of a length of the affine motion compensation image sub-block in the vertical direction;
• and the control points each have a motion vector for determining the motion vector difference;
• and
• an encoding module, configured to perform encoding processing on the affine image block based on the size of the affine motion compensation image sub-block.

A non-transitory computer-readable medium for storing bit string of a video, comprising:

• a bit string stored in the non-transitory computer-readable medium, the bit string comprising an encoded sequence of frames of a video, wherein the sequence of frames is encoded into the bit string based on a plurality of operations comprising:
• determining a size of an affine motion compensation image sub-block in an affine image block based on a motion vector difference of the affine image block, a motion vector precision of the affine image block, a distance between control points in the affine image block, and a size of the affine image block, so that a length of the affine image block in a horizontal direction is an integer multiple of a length of the affine motion compensation image sub-block in the horizontal direction, and a length of the affine image block in a vertical direction is an integer multiple of a length of the affine motion compensation image sub-block in the vertical direction;
• and the control points each have a motion vector for determining the motion vector difference;
• and
• performing encoding processing on the affine image block based on the size of the affine motion compensation image sub-block.