Methods and systems for performing in-loop luma mapping with chroma scaling are described. One of the methods includes receiving a chrome block and a luma block associated with a picture. The method also includes determining luma scaling information associated with the luma block. The method also includes determining a luma scaling factor of the luma block based on the luma scaling information. The method also includes determining the chroma scaling factor based on a value of the luma scaling factor. The method also includes processing residuals of the chroma block using the chroma scaling factor.

There is provided a method for processing an input signal (700). The input signal (700) is processed at least by converting the input signal (700) from a first colour space to a second colour space, to produce a first processed signal. The processed signal is encoded by a first encoding module (703) to generate a first encoded signal (710). A decoded signal is generated by decoding the first encoded signal (710). The decoded signal is processed at least by converting the decoded signal from the second colour space to the first colour space to produce a second processed signal. The second processed signal and the input signal (700) are processed by a second encoding module (707) to generate a second encoded signal (720).

There is provided a method for processing an input signal (700). The input signal (700) is processed at least by converting the input signal (700) from a first colour space to a second colour space, to produce a first processed signal. The processed signal is encoded by a first encoding module (703) to generate a first encoded signal (710). A decoded signal is generated by decoding the first encoded signal (710). The decoded signal is processed at least by converting the decoded signal from the second colour space to the first colour space to produce a second processed signal. The second processed signal and the input signal (700) are processed by a second encoding module (707) to generate a second encoded signal (720).

Methods and apparatuses for video encoding, comprising: receiving a video sequence; encoding the video sequence by using control flags for luma mapping with chroma scaling (LMCS) at a sequence level, a picture level, or a slice level, wherein the sequence level, the picture level, and the slice level are levels ranking from high to low; signaling a first control flag indicating whether the LMCS is enabled at a first level; and in response to the first control flag indicating the LMCS is enabled at the first level, signaling a second control flag indicating whether LMCS is enabled at a second level, wherein: the LMCS is enabled at the second level when a value of the second control flag equals to 1; the LMCS is disabled at the second level when the value of the second control flag equals to 0; and the second level is a lower level than the first level.

Methods and apparatuses for video encoding, comprising: receiving a video sequence; encoding the video sequence by using control flags for luma mapping with chroma scaling (LMCS) at a sequence level, a picture level, or a slice level, wherein the sequence level, the picture level, and the slice level are levels ranking from high to low; signaling a first control flag indicating whether the LMCS is enabled at a first level; and in response to the first control flag indicating the LMCS is enabled at the first level, signaling a second control flag indicating whether LMCS is enabled at a second level, wherein: the LMCS is enabled at the second level when a value of the second control flag equals to 1; the LMCS is disabled at the second level when the value of the second control flag equals to 0; and the second level is a lower level than the first level.

In one embodiment, one or more computing systems may determine a first display content to be displayed on a display. The first display content may be associated with one or more frames. The one or more computing systems may determine an optimization operation for the first display content based on one or more first parameters associated with the display or one or more second parameters associated with the one or more frames. The one or more computing systems may adjust the one or more frames based on the optimization operation. The adjusted one or more frames may have at least one optimized attribute comparing to the one or more frames before being adjusted. The one or more computing systems may output the adjusted one or more frames to the display to represent the first display content.

In a depth image compressing section of an image processing device, a depth image operation section generates a depth image by operation using photographed stereo images. A difference image obtaining section generates a difference image between an actually measured depth image and the computed depth image. In a depth image decompressing section of a content processing device, a depth image operation section generates a depth image by operation using the transmitted stereo images. A difference image adding section restores a depth image by adding the computed depth image to the transmitted difference image.

A method for transforming high dynamic range (HDR) video data into standard dynamic range (SDR) video data and encoding the SDR video data so that the HDR video data may be recovered at the decoder includes generating a tone map describing a transformation applied to the HDR video data to generate the SDR video data. The generated tone map describes the transformation as the multiplication of each HDR pixel in the HDR video data by a scalar to generate the SDR video data. The tone map is then modeled as a reshaping transfer function and the HDR video data is processed by the reshaping transfer function to generate the SDR video data. The reshaping transfer function is then inverted and described in a self-referential metadata structure. The SDR video data is then encoded including the metadata structure defining the inverse reshaping transfer function.

A method for transforming high dynamic range (HDR) video data into standard dynamic range (SDR) video data and encoding the SDR video data so that the HDR video data may be recovered at the decoder includes generating a tone map describing a transformation applied to the HDR video data to generate the SDR video data. The generated tone map describes the transformation as the multiplication of each HDR pixel in the HDR video data by a scalar to generate the SDR video data. The tone map is then modeled as a reshaping transfer function and the HDR video data is processed by the reshaping transfer function to generate the SDR video data. The reshaping transfer function is then inverted and described in a self-referential metadata structure. The SDR video data is then encoded including the metadata structure defining the inverse reshaping transfer function.

Aspects of the disclosure provide methods and apparatuses for video data processing. In some examples, an apparatus for video data processing includes processing circuitry. The processing circuitry determines a first syntax element for coding control in a first scope of coded video data in a bitstream. The first syntax element is associated with a coding tool for processing transform coefficients with a dynamic range that is extended from a predetermined dynamic range. The dynamic range is associated with an extended precision. Then, in response to the first syntax element being a first value indicative of disabling of the coding tool in the first scope, the processing circuitry decodes the first scope of coded video data in the bitstream that includes one or more second scopes of coded video data without invoking the coding tool.