Ultra light models and decision fusion for fast video coding

A method for encoding a current block of video using intra-prediction, comprising:

• obtaining pre-calculated features, wherein the pre-calculated features comprise at least three of:
• a non-linear function of a quantization parameter;
• respective errors between the current block and respective prediction blocks, wherein each prediction block corresponds to an available intra-prediction mode;
• a mean of the current block;
• a variance of the current block;
• or
• a sum-of-absolute values of a convolution block, the convolution block obtained from the current block;
• obtaining, using a machine-learning (ML) model, an ML intra-prediction mode, wherein the ML model receives the pre-calculated features as inputs;
• selecting an encoding intra-prediction mode using at least the ML intra-prediction mode, wherein selecting the encoding intra-prediction mode using at least the ML intra-prediction mode comprises:
• obtaining a most-probable intra-prediction mode from amongst available intra-prediction modes for encoding the current block;
• and
• using a decision matrix to select the encoding intra-prediction mode, wherein the encoding intra-prediction mode is one of the ML intra-prediction mode or the most-probable intra-prediction mode;
• encoding, in a compressed bitstream, the encoding intra-prediction mode;
• and
• encoding the current block using the encoding intra-prediction mode.

An apparatus for encoding a current block of video using intra-prediction, wherein the apparatus:

• obtains, using a machine-learning (ML) model, ML intra-prediction modes;
• obtains most-probable intra-prediction modes from amongst available intra-prediction modes for encoding the current block;
• selects, as an encoding intra-prediction mode, one of the ML intra-prediction modes or one of the most-probable intra-prediction modes, wherein the selecting is based on relative reliabilities of the ML intra-prediction mode and the most-probable intra-prediction mode, wherein the relative reliabilities are values of a decision matrix generated during training of the ML model;
• encodes, in a compressed bitstream, the encoding intra-prediction mode;
• and
• encodes the current block using the encoding intra-prediction mode.