Patent classifications
H04N19/80
Method for image processing and apparatus for implementing the same
A method of method of processing an image includes: determining estimates of parameters of an auto-regressive, AR, parametric model of noise contained in the image, according to which a current noise pixel is computed as a combination of a linear combination of P previous noise pixels in a causal neighborhood of the current noise pixel weighted by respective AR model linear combination parameters (φ.sub.1, . . . , φ.sub.P) with a generated noise sample corresponding to an additive Gaussian noise of AR model variance parameter (σ), generating a noise template of noise pixels based on the estimated AR model parameters, wherein the noise template is of a predetermined pixel size smaller than the pixel size of the image, determining an estimate (σ.sub.P) of a variance of the noise template, and based on a comparison of the estimated variance (σ.sub.P) with a predetermined threshold (T.sub.σ), correcting the AR model variance parameter (σ).
Method for region-wise scalability with adaptive resolution change
Systems and methods for coding and decoding are provided. A method includes receiving a coded video stream including a picture partitioned into a plurality of sub-pictures, and further including adaptive resolution change (ARC) information that is signaled directly within a header of a sub-picture from among the plurality of sub-pictures, or that is signaled directly within a parameter set without any of the ARC information within the parameter set being referenced in any header or other parameter set, or that is provided within the parameter set and referenced in the header; and adaptively changing resolution of the sub-picture based on the ARC information.
Sample adaptive offset (SAO) parameter signaling
A method for sample adaptive offset (SAO) filtering and SAO parameter signaling in a video encoder is provided that includes determining SAO parameters for largest coding units (LCUs) of a reconstructed picture, wherein the SAO parameters include an indicator of an SAO filter type and a plurality of SAO offsets, applying SAO filtering to the reconstructed picture according to the SAO parameters, and entropy encoding LCU specific SAO information for each LCU of the reconstructed picture in an encoded video bit stream, wherein the entropy encoded LCU specific SAO information for the LCUs is interleaved with entropy encoded data for the LCUs in the encoded video bit stream. Determining SAO parameters may include determining the LCU specific SAO information to be entropy encoded for each LCU according to an SAO prediction protocol.
Sample adaptive offset (SAO) parameter signaling
A method for sample adaptive offset (SAO) filtering and SAO parameter signaling in a video encoder is provided that includes determining SAO parameters for largest coding units (LCUs) of a reconstructed picture, wherein the SAO parameters include an indicator of an SAO filter type and a plurality of SAO offsets, applying SAO filtering to the reconstructed picture according to the SAO parameters, and entropy encoding LCU specific SAO information for each LCU of the reconstructed picture in an encoded video bit stream, wherein the entropy encoded LCU specific SAO information for the LCUs is interleaved with entropy encoded data for the LCUs in the encoded video bit stream. Determining SAO parameters may include determining the LCU specific SAO information to be entropy encoded for each LCU according to an SAO prediction protocol.
CHROMA PROCESSING FOR VIDEO ENCODING AND DECODING
Encoding or decoding picture information can involve determining a first scaling factor varying with a first granularity to scale a chroma prediction residual associated with chroma information included in the picture information; determining a second scaling factor varying with a second granularity finer than the first granularity; scaling the chroma prediction residual based on a combination of the first scaling factor and the second scaling factor to provide a scaled chroma prediction residual with the second granularity; and encoding or decoding at least a portion of the picture information based on the scaled chroma prediction residual.
FILTER SHAPE SWITCHING
Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry. The processing circuitry reconstructs a first sample in a video of a coded video bitstream based on a non-linear mapping based filter with a first filter shape configuration of a plurality of filter shape configurations. The plurality of filter shape configurations including at least two filter shape configurations that are based on a same geometric shape. The processing circuitry determines a switch from the first filter shape configuration to a second filter shape configuration. The processing circuitry reconstructs a second sample in the video based on the non-linear mapping based filter with the second filter shape configuration.
FILTER SHAPE SWITCHING
Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry. The processing circuitry reconstructs a first sample in a video of a coded video bitstream based on a non-linear mapping based filter with a first filter shape configuration of a plurality of filter shape configurations. The plurality of filter shape configurations including at least two filter shape configurations that are based on a same geometric shape. The processing circuitry determines a switch from the first filter shape configuration to a second filter shape configuration. The processing circuitry reconstructs a second sample in the video based on the non-linear mapping based filter with the second filter shape configuration.
Directed interpolation and data post-processing
An encoding device evaluates a plurality of processing and/or post-processing algorithms and/or methods to be applied to a video stream, and signals a selected method, algorithm, class or category of methods/algorithms either in an encoded bitstream or as side information related to the encoded bitstream. A decoding device or post-processor utilizes the signaled algorithm or selects an algorithm/method based on the signaled method or algorithm. The selection is based, for example, on availability of the algorithm/method at the decoder/post-processor and/or cost of implementation. The video stream may comprise, for example, downsampled multiplexed stereoscopic images and the selected algorithm may include any of upconversion and/or error correction techniques that contribute to a restoration of the downsampled images.
Directed interpolation and data post-processing
An encoding device evaluates a plurality of processing and/or post-processing algorithms and/or methods to be applied to a video stream, and signals a selected method, algorithm, class or category of methods/algorithms either in an encoded bitstream or as side information related to the encoded bitstream. A decoding device or post-processor utilizes the signaled algorithm or selects an algorithm/method based on the signaled method or algorithm. The selection is based, for example, on availability of the algorithm/method at the decoder/post-processor and/or cost of implementation. The video stream may comprise, for example, downsampled multiplexed stereoscopic images and the selected algorithm may include any of upconversion and/or error correction techniques that contribute to a restoration of the downsampled images.
Video intra prediction using hybrid recursive filters
An example method of decoding video data includes obtaining, from a coded video bitstream and for a current block of the video data, an indication of an intra-prediction mode that identifies an initial predictive block; filtering, in parallel, samples in a current line of a plurality of lines of the initial predictive block based on filtered values of samples in a preceding line of the plurality of lines and unfiltered values of samples in the current line to generate filtered values for samples for the current line; and reconstructing, using intra prediction, values of samples of the current block based on the filtered values of the samples of the current initial predictive block and residual data for the current block that represents a difference between the filtered values of the samples of the current initial predictive block and the values of samples of the current block.