Innovations in scalable compression and decompression of point cloud data are described. For example, after an encoder uses a transform such as a region-adaptive hierarchical transform (“RAHT”) on attributes of occupied points in point cloud data, the encoder separates transform coefficients into partitions. The partitions can be associated with different regions of a point cloud frame (spatial location scalability), different spatial resolutions of point cloud data (spatial resolution scalability), different reconstruction quality levels (SNR scalability), different point cloud frames organized in temporal layers (temporal resolution scalability), or different combinations of the preceding types of partitions. For decoding, a decoder can select all of the partitions or a subset of the partitions. The decoder decodes encoded data for the selected partitions, applying an inverse transform such as an inverse RAHT to transform coefficients for attributes of occupied points in point cloud data.

The present technology relates to a reproduction device, a reproduction method, and a recording medium capable of displaying graphics with a broader dynamic range of luminance and appropriate brightness. The reproduction device reads a Tone_map stream and a graphics stream of an extended graphics from a recording device, wherein the recording device records the Tone_map stream including HDR information indicating a luminance feature of the extended graphics which are first graphics with a first luminance range different from and broader than a second luminance range, and a luminance conversion definition information used in luminance conversion from the extended graphics to standard graphics. The standard graphics are graphics with the second luminance range. The reproduction device converts the extended graphics into the standard graphics based on the luminance conversion definition information of the extended graphics included in the Tone map stream.

The present technology relates to a reproduction device, a reproduction method, and a recording medium capable of displaying graphics with a broader dynamic range of luminance and appropriate brightness. The reproduction device reads a Tone_map stream and a graphics stream of an extended graphics from a recording device, wherein the recording device records the Tone_map stream including HDR information indicating a luminance feature of the extended graphics which are first graphics with a first luminance range different from and broader than a second luminance range, and a luminance conversion definition information used in luminance conversion from the extended graphics to standard graphics. The standard graphics are graphics with the second luminance range. The reproduction device converts the extended graphics into the standard graphics based on the luminance conversion definition information of the extended graphics included in the Tone map stream.

A method of encoding a digital video data applies adaptive pre-processing to data representing high dynamic range (HDR) and/or wide color gamut (WCG) image data prior to encoding and complementary post-processing to the data after decoding in order to allow at least partial reproduction of the HDR and/or WCG data. The example methods apply one or more color space conversions, and a perceptual transfer functions to the data prior to quantization. The example methods apply inverse perceptual transfer functions and inverse color space conversions after decoding to recover the HDR and/or WCG data. The transfer functions are adaptive so that different transfer functions may be applied to video data sets including different groups of frames, frames or processing windows in a single frame. Information on the data set and information on the applied transfer function is passed as metadata from the encoder to the decoder.

A method of encoding a digital video data applies adaptive pre-processing to data representing high dynamic range (HDR) and/or wide color gamut (WCG) image data prior to encoding and complementary post-processing to the data after decoding in order to allow at least partial reproduction of the HDR and/or WCG data. The example methods apply one or more color space conversions, and a perceptual transfer functions to the data prior to quantization. The example methods apply inverse perceptual transfer functions and inverse color space conversions after decoding to recover the HDR and/or WCG data. The transfer functions are adaptive so that different transfer functions may be applied to video data sets including different groups of frames, frames or processing windows in a single frame. Information on the data set and information on the applied transfer function is passed as metadata from the encoder to the decoder.

There is provided a method of encoding a video signal, the method comprising: receiving an input frame; processing the input frame to generate at least one set of residuals data, the residuals data enabling a decoder to reconstruct the input frame from a reference reconstructed frame; and, applying a run-length coding operation to the set of residuals data, wherein the run-length coding operation comprises generating a run-length encoded bytestream comprising a set of symbols representing non-zero data values of the residuals data set and counts of consecutive zero values of the residuals data set. In certain embodiments the method comprises apply a Huffman coding operation to the set of symbols. A method of decoding is also provided as well as apparatuses and a computer readable medium.

There is provided a method of encoding a video signal, the method comprising: receiving an input frame; processing the input frame to generate at least one set of residuals data, the residuals data enabling a decoder to reconstruct the input frame from a reference reconstructed frame; and, applying a run-length coding operation to the set of residuals data, wherein the run-length coding operation comprises generating a run-length encoded bytestream comprising a set of symbols representing non-zero data values of the residuals data set and counts of consecutive zero values of the residuals data set. In certain embodiments the method comprises apply a Huffman coding operation to the set of symbols. A method of decoding is also provided as well as apparatuses and a computer readable medium.

A disclosed configuration includes a system (or a computer implemented method or a non-transitory computer readable medium) for automatically preprocessing higher dynamic range image data into lower dynamic range image data through a data adaptive tuning process. By automatically preprocessing the higher dynamic range image data into the lower dynamic range image data through the data adaptive tuning process, an existing encoding process for encoding the standard dynamic range image data can be applied to the lower dynamic range image data while preserving metadata sufficient to recover image fidelity even in the high dynamic range. In one aspect, the system (or a computer implemented method or a non-transitory computer readable medium) provides for backwards compatibility between high dynamic range video services and existing standard dynamic range services. In one aspect, regrading is applied in a domain that is perceptually more uniform than the domain it is initially presented.

A disclosed configuration includes a system (or a computer implemented method or a non-transitory computer readable medium) for automatically preprocessing higher dynamic range image data into lower dynamic range image data through a data adaptive tuning process. By automatically preprocessing the higher dynamic range image data into the lower dynamic range image data through the data adaptive tuning process, an existing encoding process for encoding the standard dynamic range image data can be applied to the lower dynamic range image data while preserving metadata sufficient to recover image fidelity even in the high dynamic range. In one aspect, the system (or a computer implemented method or a non-transitory computer readable medium) provides for backwards compatibility between high dynamic range video services and existing standard dynamic range services. In one aspect, regrading is applied in a domain that is perceptually more uniform than the domain it is initially presented.

For each image in a set of images, a representation of the image at a first level of quality is derived using a first representation of the image at a second, higher level of quality and is output for processing by a decoder. Configuration data is output for processing by the decoder to enable the decoder to detect whether or not the first representation of a given image in the set of images is to be reconstructed using residual data for the given image, the residual data: (i) being useable to reconstruct the first representation using a second representation of the image at the second level of quality, the second representation being based on the representation of the image at the first level of quality, and (ii) being derived based on the first representation and the second representation.