公开(公告)号：US20240422345A1

公开(公告)日：2024-12-19

申请号：US18687768

申请日：2022-08-05

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Peng YIN ,  Fangjun PU ,  Taoran LU ,  Arjun ARORA ,  Guan-Ming SU ,  Tao CHEN ,  Sean Thomas MCCARTHY ,  Walter J. HUSAK

IPC: H04N19/517 ,  H04N19/117 ,  H04N19/82

Abstract: An input image represented in an input domain is received from an input video signal. Forward reshaping is performed on the input image to generate a forward reshaped image represented in a reshaped image domain. Non-reshaping encoding operations are performed to encode the reshaped image into an encoded video signal. At least one of the non-reshaping encoding operations is implemented with an ML model that has been previously trained with training images in one or more training datasets in a preceding training stage. A recipient device of the encoded video signal is caused to generate a reconstructed image from the forward reshaped image.

公开(公告)号：US20240007682A1

公开(公告)日：2024-01-04

申请号：US18252357

申请日：2021-11-10

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Janos HORVATH ,  Harshad KADU ,  Guan-Ming SU

IPC: H04N19/98 ,  H04N19/105 ,  H04N19/186

CPC classification number: H04N19/98 ,  H04N19/105 ,  H04N19/186

Abstract: An input image of a first bit depth in an input domain is received. Forward reshaping operations are performed on the input image to generate a forward reshaped image of a second bit depth in a reshaping domain. An image container containing image data derived from the forward reshaped image is encoded into an output video signal of the second bit depth.

公开(公告)号：US20230368344A1

公开(公告)日：2023-11-16

申请号：US18248309

申请日：2021-10-14

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Guan-Ming SU

IPC: G06T5/00 ,  H04N19/186 ,  G06V10/56 ,  G06V10/60

CPC classification number: G06T5/007 ,  H04N19/186 ,  G06V10/56 ,  G06V10/60 ,  G06T2207/10024 ,  G06T2207/20208

Abstract: Using a standard-based RGB to YCbCr color transform a new RGB to YCC 3×3 transformation matrix and a 3×1 offset vector are derived under a set of coding-efficiency constraints. The new RGB to YCC 3×3 transform comprises a luminance scaling factor and a 2×2 chroma sub-matrix that preserves the energy of the standard-based RGB to YCbCr transform while maintaining or improving coding efficiency. It also adds support for an authorization or watermarking mechanism in streaming video applications. Examples of using the new color transform using image reshaping are also provided.

公开(公告)号：US20230164366A1

公开(公告)日：2023-05-25

申请号：US17920391

申请日：2021-04-21

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Guan-Ming SU ,  Harshad KADU

IPC: H04N19/98 ,  G06T5/00 ,  H04N19/186 ,  H04N23/741

CPC classification number: H04N19/98 ,  G06T5/007 ,  H04N19/186 ,  H04N23/741 ,  G06T2207/20208

Abstract: A method, for generating (a) a forward reshaping function for compressing an input high-dynamic range (HDR) image into a reshaped standard-dynamic-range (SDR) image and (b) a backward reshaping function for decompressing the reshaped SDR image into a reconstructed HDR image, includes (i) optimizing the forward reshaping function to minimize a deviation between the reshaped SDR image and an input SDR image corresponding to the input HDR image, (ii) optimizing the backward reshaping function to minimize a deviation between the reconstructed HDR image and the input HDR image, and (iii) until a termination condition is met, applying a correction to the input SDR image and reiterating, based on the input SDR image as corrected, the steps of optimizing the forward and backward reshaping functions.

公开(公告)号：US20210195221A1

公开(公告)日：2021-06-24

申请号：US17054495

申请日：2019-05-09

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Qing SONG ,  Harshad KADU ,  Guan-Ming SU

IPC: H04N19/186 ,  H04N19/23 ,  H04N19/105 ,  H04N19/159 ,  H04N19/44

Abstract: 3D mapping statistics are generated for a first image of a first dynamic range and a second image of a second dynamic range different from the first dynamic range. Multivariate multiple regression (MMR) coefficients are generated by solving an optimization problem formulated using an MMR matrix built with the 3D mapping statistics without a letterbox constraint, and used to generate chroma mappings for predicting chroma codeword values of the second image. It is determined whether a letterbox exists in the images. If so, it is determined whether the chroma mappings accurately predict chroma codeword values in the second image. A reconstructed image generated by a recipient device by backward reshaping one of the images is rendered by a display device operating in conjunction with the recipient device.

公开(公告)号：US20210150812A1

公开(公告)日：2021-05-20

申请号：US17045941

申请日：2019-04-08

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Guan-Ming SU ,  Qing SONG

IPC: G06T17/20 ,  G06T3/40 ,  G06T9/00 ,  G06K9/62 ,  G06N3/04

Abstract: Methods and systems for mapping images from a first dynamic range to a second dynamic range using a set of reference color-graded images and neural networks are described. Given a first and a second image representing the same scene but at a different dynamic range, a neural network (NN) model is selected from a variety of NN models to determine an output image which approximates the second image based on the first image and the second image. The parameters of the selected NN model are derived according to an optimizing criterion, the first image and the second image, wherein the parameters include node weights and/or node biases for nodes in the layers of the selected NN model. Example HDR to SDR mappings using global-mapping and local-mapping representations are provided.

公开(公告)号：US20210150680A1

公开(公告)日：2021-05-20

申请号：US16623326

申请日：2018-06-13

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Neeraj J. GADGIL ,  Guan-Ming SU ,  Tao CHEN ,  Yoon Yung LEE

IPC: G06T5/00 ,  G06T5/40 ,  H04N19/186 ,  H04N19/98

Abstract: A standard dynamic range (SDR) image is received. Composer metadata is generated for mapping the SDR image to an enhanced dynamic range (EDR) image. The composer metadata specifies a backward reshaping mapping that is generated from SDR-EDR image pairs in a training database. The SDR-EDR image pairs comprise SDR images that do not include the SDR image and EDR images that corresponds to the SDR images. The SDR image and the composer metadata are encoded in an output SDR video signal. An EDR display operating with a receiver of the output SDR video signal is caused to render an EDR display image. The EDR display image is derived from a composed EDR image composed from the SDR image based on the composer metadata.

公开(公告)号：US20190320191A1

公开(公告)日：2019-10-17

申请号：US16303028

申请日：2017-05-17

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Qing SONG ,  Guan-Ming SU ,  Qian CHEN ,  Tao CHEN

IPC: H04N19/30 ,  H04N19/124 ,  H04N19/85 ,  H04N19/98 ,  H04N19/136 ,  H04N19/186

Abstract: Methods and systems for adaptive chroma reshaping are discussed. Given an input image, a luma-reshaped image is first generated based on its luma component. For each chroma component of the input image, the range of the pixel values in the luma reshaped image is divided into bins, and for each bin a maximal scale factor is generated based on the chroma pixel values in the input image corresponding to the pixels of the luma reshaped image in the bin. A forward reshaping function is generated based on a reference reshaped function and the maximal scale factors, and reshaped chroma pixel values for the chroma component are generated based on the forward reshaping function and the corresponding pixel values in the luma reshaped image. Implementations options using look-up tables for mobile platforms with limited computational resources are also described.

公开(公告)号：US20180278930A1

公开(公告)日：2018-09-27

申请号：US15988937

申请日：2018-05-24

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Guan-Ming SU ,  Sheng QU ,  Hubert KOEPFER ,  Yufei YUAN ,  Samir HULYALKAR

IPC: H04N19/105 ,  H04N19/192 ,  H04N19/147 ,  H04N19/30 ,  H04N19/98 ,  G06F17/18 ,  H04N19/16

CPC classification number: H04N19/105 ,  G06F17/18 ,  H04N19/147 ,  H04N19/16 ,  H04N19/192 ,  H04N19/30 ,  H04N19/98 ,  H05K999/99

Abstract: Inter-color image prediction is based on multi-channel multiple regression (MMR) models. Image prediction is applied to the efficient coding of images and video signals of high dynamic range. MMR models may include first order parameters, second order parameters, and cross-pixel parameters. MMR models using extension parameters incorporating neighbor pixel relations are also presented. Using minimum means-square error criteria, closed form solutions for the prediction parameters are presented for a variety of MMR models.

公开(公告)号：US20180115777A1

公开(公告)日：2018-04-26

申请号：US15795093

申请日：2017-10-26

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Sankaranarayanan PIRAMANAYAGAM ,  Qing SONG ,  Guan-Ming SU

IPC: H04N19/186 ,  H04N19/182 ,  H04N19/587

CPC classification number: H04N19/186 ,  G06T5/007 ,  G06T7/00 ,  G06T9/00 ,  G06T2207/20208 ,  G09G5/005 ,  G09G2320/0673 ,  G09G2320/0693 ,  G09G2340/02 ,  G09G2370/04 ,  H04N19/182 ,  H04N19/587 ,  H04N19/68 ,  H04N19/98

Abstract: Methods for screen-adaptive decoding of video with high dynamic range (HDR) are described. The methods combine the traditional compositing and display management steps into one screen-adaptive compositing step. Given decoded standard dynamic range (SDR) input data, metadata related to the prediction of output HDR data in a reference dynamic range, and the dynamic range of a target display, new output luma and chroma prediction functions are generated that map directly the input SDR data to output HDR data in the target dynamic range, thus eliminating the display management step.