US-12627805-B2 - Coding framework for image-related parameters

US12627805B2US 12627805 B2US12627805 B2US 12627805B2US-12627805-B2

Abstract

A system and a method are disclosed for processing data. The method includes receiving, by a decoding circuit, a first input bitstream including a first set of coefficients associated with a first group of pixels of a display device, the first set of coefficients having a first format that is different from a second format associated with an output data of the decoding circuit, a first portion indicating that one or more of the coefficients in the first set have absolute values that are greater than zero, and a second portion indicating that a plurality of consecutive coefficients in the first set have absolute values that are less than or equal to a first value, and changing image data for displaying an image on the display device, based on the first input bitstream.

Inventors

Harshad Kadu

Assignees

SAMSUNG DISPLAY CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20240410

Claims (20)

1 . A method for processing data, the method comprising: receiving, by a decoding circuit, a first input bitstream comprising: a first set of coefficients associated with a first group of pixels of a display device, the first set of coefficients having a first format that is different from a second format associated with an output data of the decoding circuit; a first portion indicating that one or more of the coefficients in the first set have absolute values that are greater than zero; and a second portion indicating that each of a plurality of consecutive coefficients in the first set has an absolute value that is less than or equal to a first value, a single bit of the second portion indicating that each of the plurality of the consecutive coefficients in the first set has the absolute value that is less than or equal to the first value; and changing image data for displaying an image on the display device, based on the first input bitstream.
2 . The method of claim 1 , wherein: the plurality of consecutive coefficients comprises all the coefficients in the first set; the second portion comprises a no-large coefficients (NLC) flag; and the first set corresponds to a chroma channel associated with the first group of pixels.
3 . The method of claim 1 , wherein: the plurality of consecutive coefficients comprises all the coefficients in the first set following a first coefficient of the first set; the second portion comprises a no-more-large coefficients (NMLC) flag; and the first set corresponds to a luma channel associated with the first group of pixels.
4 . The method of claim 1 , wherein the first value is one.
5 . The method of claim 1 , wherein the first portion comprises at least one of an indicator indicating a last significant-coefficient location, a significance map, or a skip flag.
6 . The method of claim 5 , wherein: the first portion comprises the indicator indicating the last significant-coefficient location; and the indicator is encoded in accordance with a Huffman codebook.
7 . The method of claim 5 , wherein the first portion comprises the significance map, and the significance map comprises bits representing each coefficient in the first set, from a first coefficient to a last significant coefficient, except for bits representing the first coefficient or the last significant coefficient.
8 . The method of claim 5 , wherein: the first portion comprises the significance map; and the significance map comprises one or more significant bits and one or more last-bit indicator bits, one of the one or more last-bit indicator bits indicating that an adjacent significant bit is a last significant bit.
9 . The method of claim 5 , wherein: the first set corresponds to a chroma channel associated with the first group of pixels; the first portion comprises the skip flag in a first state; and the skip flag is configured to indicate, in a second state, that all of the coefficients in the first set are equal to zero.
10 . The method of claim 1 , further comprising generating the first input bitstream based on: a first combined bitstream comprising the first portion associated with the first set of coefficients associated with the first group of pixels and comprising a first portion associated with a second set of coefficients associated with a second group of pixels; and a second combined bitstream comprising the second portion associated with the first set of coefficients associated with the first group of pixels and comprising a second portion associated with the second set of coefficients associated with the second group of pixels.
11 . The method of claim 10 , wherein the generating the first input bitstream based on the first combined bitstream and the second combined bitstream comprises performing a decompression operation on the first combined bitstream or the second combined bitstream.
12 . The method of claim 11 , wherein the decompression operation comprises an inverse binary arithmetic coding (BAC) operation or an inverse run-length coding (RLC) operation.
13 . The method of claim 1 , wherein the first input bitstream comprises a third portion comprising indicator bits indicating absolute values of one or more of the coefficients in the first set interleaved with indicator bits indicating signs of the one or more of the coefficients in the first set.
14 . The method of claim 13 , wherein the absolute values are encoded in accordance with an Exponential-Golomb codebook.
15 . The method of claim 13 , wherein: the first set corresponds to a luma channel associated with the first group of pixels; a first coefficient in the first set is represented by an encoded form of its actual absolute value; and at least one of the coefficients in the first set, following the first coefficient of the first set, has an absolute that is represented by an encoded form of a value that is equal to an absolute value of the at least one of the coefficients minus one.
16 . The method of claim 1 , wherein: the first set corresponds to a luma channel associated with the first group of pixels, and the method further comprises decoding the first set based on assuming that an absolute value of a first coefficient of the luma channel is significant.
17 . A system for data processing, the system comprising: a processing circuit; and a memory storing instructions, which, when executed by the processing circuit, cause the processing circuit to perform: receiving, at a decoder, a first input bitstream comprising: a first set of coefficients associated with a first group of pixels of a display device, the first set of coefficients having a first format that is different from a second format associated with an output data of the decoder; a first portion indicating that one or more of the coefficients in the first set have absolute values that are greater than zero; and a second portion indicating that each of a plurality of consecutive coefficients in the first set has an absolute value that is less than or equal to a first value, a single bit of the second portion indicating that each of the plurality of the consecutive coefficients in the first set has the absolute value that is less than or equal to the first value; and changing image data for displaying an image on the display device, based on the first input bitstream.
18 . The system of claim 17 , wherein the plurality of consecutive coefficients comprises one of: all the coefficients in the first set; or all the coefficients in the first set following a first coefficient of the first set.
19 . A system for data processing, the system comprising: a processing circuit; and a memory storing instructions, which, when executed by the processing circuit, cause the processing circuit to perform: receiving, at an encoder, input data comprising a first set of coefficients associated with a first group of pixels of a display, the first set of coefficients having a first format; generating a first output bitstream, representing the first set of coefficients in a second format that is different from the first format, the first output bitstream comprising: a first portion indicating that one or more of the coefficients in the first set have absolute values that are greater than zero; and a second portion indicating that each of a plurality of consecutive coefficients in the first set has an absolute value that is less than or equal to a first value, a single bit of the second portion indicating that each of the plurality of the consecutive coefficients in the first set has the absolute value that is less than or equal to the first value; and changing image data, for displaying an image on the display, based on the first output bitstream.
20 . The system of claim 19 , wherein the plurality of consecutive coefficients comprises one of: all the coefficients in the first set; or all the coefficients in the first set following a first coefficient of the first set.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims the priority benefit under 35 U.S.C. § 119 (e) of U.S. Provisional Application No. 63/549,321, filed on Feb. 2, 2024, the disclosure of which is incorporated by reference in its entirety as if fully set forth herein. TECHNICAL FIELD The disclosure generally relates to displays. More particularly, the subject matter disclosed herein relates to improvements to processing compensation parameters for improving the quality of an image displayed on a display device. SUMMARY Compensation parameters for improving the quality of an image to be displayed on a display device may include parameters for a mura compensation algorithm (MCA). Compensation parameters may allow for a reduction in mura defects in a display of a display device. As used herein, “mura” refers to a non-uniform brightness and/or non-uniform chromaticity of pixels on a display, which may result from the manufacturing process. Mura defects may manifest themselves (e.g., may be observed) when an image of uniform brightness is displayed on the display. For example, mura defects may be detected when an image of uniform brightness is displayed but the pixels show different brightnesses. During the manufacturing process, mura-related defects may be captured in an image. An MCA may use parameters derived from the captured image to compensate for mura. MCA parameters may be mapped to an image (e.g., an MCA-parameter image), the MCA parameters may be compressed and stored in the display device. Compressing MCA parameters may be significantly different from compressing natural-image data. For example, MCA parameters may include data that is not typical natural image data. MCA parameters may include three values corresponding to each pixel in the image. However, instead of allowing a natural image to be displayed, the MCA parameters provide information for how to adjust luma (e.g., grayscale) components and/or chroma (e.g., color) components of an image to be displayed on a display device, such that the quality of a displayed picture may be improved. As such, MCA parameters may exhibit characteristics that are different from characteristics of natural-image data. For example, MCA parameters may be relatively random, when compared to natural-image data, and may change more quickly (e.g., more dramatically) from one pixel to the next. Additionally, noise-like high frequency components of an MCA-parameter image may be important for compensating mura. Codecs (e.g., image and/or video compression codecs) for use with natural image data may not be suitable (e.g., may not be ideal or optimal) for compressing MCA parameters. As used herein, a “codec” refers to a device or program configured to compress and/or decompress image-related data. Although MCA parameters may be stored like a natural image, compressing MCA parameters with a natural-image codec may result in unsatisfactory performance. To overcome these issues, systems and methods are described herein for improved codecs for compressing MCA parameters. Although the present disclosure refers to codecs for compressing MCA parameters, aspects of some embodiments of the present disclosure may be useful for improving codecs for processing natural image data. In some embodiments, a method comprises converting input data from a first format to a second format by encoding portions of the input data with a no-more-large-coefficients flag or with a no-large-coefficients flag. Aspects of some embodiments of the present disclosure improve on previous methods by allowing MCA-parameter images to be compressed and reconstructed more accurately than with previous methods, while using the same number of bits. A more accurately reconstructed MCA-parameter image, in turn, may allow for improved picture quality as observed on a display device. Aspects of some embodiments of the present disclosure allow for parallel encoding and/or decoding based on separating out different components of binary data and encoding the different components in separate bitstreams. According to some embodiments of the present disclosure, there is provided a method for processing data including receiving, by a decoding circuit, a first input bitstream including a first set of coefficients associated with a first group of pixels of a display device, the first set of coefficients having a first format that is different from a second format associated with an output data of the decoding circuit, a first portion indicating that one or more of the coefficients in the first set have absolute values that are greater than zero, and a second portion indicating that a plurality of consecutive coefficients in the first set have absolute values that are less than or equal to a first value, and changing image data for displaying an image on the display device, based on the first input bitstream. The plurality of consecutive coefficients may include all the coefficients in the first set, the second portio