Motion field-based reference frame rendering for motion compensated prediction in video coding

An apparatus, comprising:

• a processor;
• and
• a non-transitory storage medium that includes instructions executable by the processor to carry out a method comprising:
• determining a first frame to be predicted, the first frame being in a video sequence;
• determining a first reference frame from the video sequence for forward inter prediction of the first frame;
• determining a second reference frame from the video sequence for backward inter prediction of the first frame;
• determining a respective motion field for blocks of the first frame using at least one of hte first reference frame or the second reference frame;
• determining parameters forming an affine homographic model using the motion field;
• rendering a current block of a reconstructed reference frame at a co-located position within a motion field-based reference frame by applying the affine homographic model to the current block;
• and
• performing a prediction process for the first frame using the motion field-based reference frame.

An apparatus, comprising:

• a processor;
• and
• a non-transitory storage medium that includes instructions executable by the processor to carry out a method comprising:
• determining a first frame from a video sequence;
• determining a first reference frame from the video sequence for forward inter prediction of the first frame;
• determining a second reference frame from the video sequence for backward inter prediction of the first frame;
• determining a motion field for at least some of the block of the first frame using at least one of the first reference frame or the second reference frame;
• generating at least one affine homographic model using the motion field;
• rendering a current block of a reconstructed reference frame at a co-located position within a motion field-based reference frame by applying the affine homographic model to the current block;
• and
• performing a prediction process for the first frame using the motion field-based reference frame.