Abstract: An apparatus for coding a block of a frame using intra-prediction includes a memory and a processor. The processor is configured to execute instructions stored in the memory to obtain an intra-prediction mode for coding the block of the frame; select a transform type for coding a transform block of a residual block, which results from predicting the block using the intra-prediction mode; and code the transform block using the transform type. To select the transform type includes to, in a case where the intra-prediction mode is a SMOOTH_PRED, select a ADST_ADST transform type; in a case where the intra-prediction mode is a SMOOTH_H_PRED, select a DCT_ADST transform type; and in a case where the intra-prediction mode is a SMOOTH_V_PRED, select a ADST_DCT transform type.

Abstract: A method for encoding a block of a video stream includes generating, using pixel values of the block, block features for the block; for each candidate encoding mode of candidate encoding modes, generating, using the block features and the each candidate encoding mode as inputs to a machine-learning module, a respective encoding cost; selecting, based on the respective encoding costs, a predetermined number of the candidate encoding modes; selecting, based on the respective encoding costs of the at least some encoding modes, a best mode for encoding the block; and encoding, in a compressed bitstream, the block using the best mode.

Abstract: Guided restoration is used to restore video data degraded from a video frame. The video frame is divided into restoration units (RUs) which each correspond to one or more blocks of the video frame. Restoration schemes are selected for each RU. The restoration schemes may indicate to use one of a plurality of neural networks trained for the guided restoration. Alternatively, the restoration schemes may indicate to use a neural network and a filter-based restoration tool. The video frame is then restored by processing each RU according to the respective selected restoration scheme. During encoding, the restored video frame is encoded to an output bitstream, and the use of the selected restoration schemes may be signaled within the output bitstream. During decoding, the restored video frame is output to an output video stream.

Abstract: A hybrid apparatus for coding a video stream includes a first encoder. The first encoder includes a neural network having at least one hidden layer, and the neural network receives source data from the video stream at a first hidden layer of the at least one hidden layer, receives side information correlated with the source data at the first hidden layer, and generates guided information using the source data and the side information. The first encoder outputs the guided information and the side information for a decoder to reconstruct the source data.

Abstract: Video coding may include generating, by a processor, a decoded frame by decoding a current frame from an encoded bitstream and outputting a reconstructed frame based on the decoded frame. Decoding includes identifying a current encoded block from the current frame, identifying a prediction coding model for the current block, wherein the prediction coding model is a machine learning prediction coding model from a plurality of machine learning prediction coding models, identifying reference values for decoding the current block based on the prediction coding model, obtaining prediction values based on the prediction coding model and the reference values, generating a decoded block corresponding to the current encoded block based on the prediction values, and including the decoded block in the decoded frame.

Abstract: Coding a block of a video frame using an intra-prediction mode is disclosed. A method includes selecting first neighboring pixels, generating second pixels for use along a second edge that is opposite the first edge of the block, and generating a prediction block that includes predicted pixels. The first neighboring pixels are peripheral to the block along a first edge of the block. The second pixels are generated using third neighboring pixels that are peripheral to a third edge of the block. The third edge is different from the first edge and the second edge. Generating the prediction block includes interpolating, using a first interpolation, the first neighboring pixels and the second pixels to obtain the predicted pixels.

Abstract: Systems and methods are disclosed for encoding and decoding video. For example, methods may include accessing an encoded bitstream; decoding loop restoration parameters in the encoded bitstream; after reconstruction of an image at a second resolution based on data of the encoded bitstream, upscaling the reconstructed image to obtain an upscaled reconstructed image at a first resolution, wherein the second resolution is less than the first resolution in at least one dimension; and applying loop restoration filtering to the upscaled reconstructed image using the loop restoration parameters to obtain a loop restored image at the first resolution.

Abstract: Systems and methods are disclosed for encoding and decoding video. For example, methods may include accessing an encoded bitstream; decoding loop restoration parameters in the encoded bitstream; after reconstruction of an image at a second resolution based on data of the encoded bitstream, upscaling the reconstructed image to obtain an upscaled reconstructed image at a first resolution, wherein the second resolution is less than the first resolution in at least one dimension; and applying loop restoration filtering to the upscaled reconstructed image using the loop restoration parameters to obtain a loop restored image at the first resolution.

Abstract: Improved transforms are used to encode and decode large video and image blocks. During encoding, a prediction residual block having a large size (e.g., larger than 32x32) is generated. The pixel values of the prediction residual block are transformed to produce transform coefficients. After determining that the transform coefficients exceed a threshold cardinality representative of a maximum transform block size (e.g., 32x32), a number of the transform coefficients are discarded such that a remaining number of transform coefficients does not exceed the threshold cardinality. A transform block is then generated using the remaining number. During decoding, after determining that the transform coefficients exceed the threshold cardinality, a number of new coefficients are added to the transform coefficients such that a total number of transform coefficients exceeds the threshold cardinality. The transform coefficients are then inverse transformed into a prediction residual block having a large size.

Abstract: Coding a block of a video frame using an intra-prediction mode is disclosed. A method includes selecting first neighboring pixels, generating second pixels for use along a second edge that is opposite the first edge of the block, and generating a prediction block that includes predicted pixels. The first neighboring pixels are peripheral to the block along a first edge of the block. The second pixels are generated using third neighboring pixels that are peripheral to a third edge of the block. The third edge is different from the first edge and the second edge. Generating the prediction block includes interpolating, using a first interpolation, the first neighboring pixels and the second pixels to obtain the predicted pixels.