Reference picture prediction for video coding

A method comprising:

• accepting a current picture for decoding:
• determining blocks of a difference picture from the accepted current picture and motion compensated predicted picture blocks;
• transforming and quantizing the blocks of a difference picture to determine quantized transform coefficients being for inclusion in a coded bitstream;
• predicting one or more predicted reference pictures using one or more previously decoded pictures stored in a multi-picture store and the quantized transform coefficients;
• determining the motion compensated predicted picture blocks and motion vectors therefor from the quantized transform coefficients and at least one of the predicted reference pictures, the determined motion vectors being for inclusion in the coded bitstream,
• wherein determining a motion compensated predicted picture block includes searching through the predicted reference pictures to determine a selected predicted reference picture for the block.

An apparatus comprising:

• an input module configured to accept a coded bitstream and to generate quantized transform coefficients and motion vectors from the coded bitstream,
• an inverse quantizer/inverse transformer configured to accept the quantized coefficients and generate a decoded difference picture;
• a summer configured to determine a decoded picture from a motion compensated predicted picture and the decoded difference picture;
• a multi-picture store for storing previously decoded pictures;
• a reference picture predictor coupled to the multi-picture store and configured to determine one or more predicted reference pictures using one or more previously decoded pictures;
• and
• a motion compensated predictor configured to determine the motion compensated prediction picture from one or a plurality of the one or more predicted reference pictures, and the motion vectors.

An apparatus comprising:

• one or more processors;
• a storage subsystem including a multi-picture store configured to store a plurality of pictures, the storage subsystem is further configured with a set of instructions that when executed by one or more of the processors cause the apparatus to:
• accept a current picture for decoding;
• determine blocks of a difference picture from the accepted current picture and motion compensated predicted picture blocks;
• transform and quantize the blocks of a difference picture to determine quantized transform coefficients being for inclusion in a coded bitstream;
• predict one or more predicted reference pictures using one or more previously decoded pictures stored in a multi-picture store and the quantized transform coefficients;
• and
• determine the motion compensated predicted picture blocks and motion vectors therefor from the quantized transform coefficients and at least one of the predicted reference pictures, the determined motion vectors being for inclusion in the coded bitstream,
• wherein determining a motion compensated predicted picture block includes searching through the predicted reference pictures to determine a selected predicted reference picture for the block, and
• wherein the predicting one or more predicted reference pictures includes optical flow analyzing that uses a current decoded picture and that may use one or more previously decoded pictures to predict motion in a set of one or more parts of a current decoded picture, combined with affine motion analyzing and image warping for determining at least a portion of at least one predicted reference picture,
• wherein affine motion parameters determined by the affine motion analysis are not transmitted to a decoder or stored for later decoding.

An apparatus comprising:

• one or more processors;
• a storage subsystem including a multi-picture store configured to store a plurality of decoded pictures, the storage subsystem is further configured with a set of instructions that when executed by one or more of the processors cause the apparatus to:
• accept a coded bitstream and to generate quantized transform coefficients and motion vectors from the coded bitstream,
• accept the quantized coefficients and generate a decoded difference picture by a process that includes inverse quantizing and inverse transforming;
• determine a decoded picture from a motion compensated predicted picture and the decoded difference picture;
• predict one or more predicted reference pictures using one or more previously decoded pictures stored in the multi-picture store;
• determine the motion compensated prediction picture from one or a plurality of the one or more predicted reference pictures, and the motion vectors,
• wherein the predicting one or more predicted reference pictures includes optical flow analyzing that uses a current decoded picture and that may use one or more previously decoded pictures to predict motion in a set of one or more parts of a current decoded picture, combined with affine motion analyzing and image warping for determining at least a portion of at least one predicted reference picture.