公开(公告)号：US11323728B2

公开(公告)日：2022-05-03

申请号：US17212701

申请日：2021-03-25

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Robin Atkins ,  Peng Yin ,  Taoran Lu ,  Fangjun Pu ,  Sean Thomas McCarthy ,  Walter J. Husak ,  Tao Chen ,  Guan-Ming Su

IPC: H04N19/31 ,  H04N19/187

Abstract: Methods and systems for frame rate scalability are described. Support is provided for input and output video sequences with variable frame rate and variable shutter angle across scenes, or for input video sequences with fixed input frame rate and input shutter angle, but allowing a decoder to generate a video output at a different output frame rate and shutter angle than the corresponding input values. Techniques allowing a decoder to decode more computationally-efficiently a specific backward compatible target frame rate and shutter angle among those allowed are also presented.

公开(公告)号：US11277646B2

公开(公告)日：2022-03-15

申请号：US17282523

申请日：2019-10-02

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Qing Song ,  Neeraj J. Gadgil ,  Guan-Ming Su ,  Peng Yin ,  Arun Raj

IPC: H04N19/86 ,  H04N19/182 ,  H04N19/189 ,  H04N19/117

Abstract: Methods and systems for reducing banding artifacts when displaying high-dynamic-range images reconstructed from coded reshaped images are described. Given an input image in a high dynamic range (HDR) which is mapped to a second image in a second dynamic range, banding artifacts in a reconstructed HDR image generated using the second image are reduced by a) in darks and mid-tone regions of the input image, adding noise to the input image before being mapped to the second image, and b) in highlights regions of the input image, modifying an input backward reshaping function, wherein the modified backward reshaping function will be used by a decoder to map a decoded version of the second image to the reconstructed HDR image. An example noise generation technique using simulated film-grain noise is provided.

公开(公告)号：US11146803B2

公开(公告)日：2021-10-12

申请号：US14772051

申请日：2014-02-14

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Guan-Ming Su ,  Samir N. Hulyalkar ,  Tao Chen

IPC: H04N19/33 ,  H04N19/124 ,  H04N19/157 ,  H04N19/44 ,  H04N19/593 ,  H04N19/70 ,  G06T3/40

Abstract: An encoder receives an input enhanced dynamic range (EDR) image to be stored or transmitted using multiple coding formats in a layered representation. A layer decomposer generates a lower dynamic range (LDR) image from the EDR image. One or more base layer (BL) encoders encode the LDR image to generate a main coded BL stream and one or more secondary coded BL streams, where each secondary BL stream is coded in a different coding format than the main coded BL stream. A single enhancement layer (EL) coded stream and related metadata are generated using the main coded BL stream, the LDR image, and the input EDR image. An output coded stream includes the coded EL stream, the metadata, and either the main coded BL stream or one of the secondary coded BL streams. Computation-scalable decoding and display management processes for EDR images are also described.

公开(公告)号：US10701375B2

公开(公告)日：2020-06-30

申请号：US16087241

申请日：2017-03-22

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Guan-Ming Su ,  Jon Scott Miller ,  Walter J. Husak ,  Yee Jin Lee ,  Harshad Kadu

IPC: H04N19/186 ,  H04N19/176 ,  G06T5/00 ,  H04N19/80 ,  H04N19/154 ,  H04N19/117 ,  H04N19/102 ,  H04N19/187 ,  H04N19/44 ,  H04N1/60 ,  H04N19/85 ,  H04N1/64

Abstract: A tone-mapping function that maps input images of a high dynamic range into reference tone-mapped images of a relatively narrow dynamic range is generated. A luma forward reshaping function is derived, based on first bit depths and second bit depths, for forward reshaping luma codewords of the input images into forward reshaped luma codewords of forward reshaped images approximating the reference tone-mapped images. A chroma forward reshaping mapping is derived for predicting chroma codewords of the forward reshaped images. Backward reshaping metadata that is to be used by recipient devices to generate a luma backward reshaping function and a chroma backward reshaping mapping is transmitted with the forward reshaped images to the recipient devices. Techniques for the joint derivation of forward luma and chroma reshaping functions are also presented.

公开(公告)号：US10440401B2

公开(公告)日：2019-10-08

申请号：US15481015

申请日：2017-04-06

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Guan-Ming Su ,  Qian Chen ,  Tao Chen ,  David Brooks ,  Samir N. Hulyalkar ,  Peng Yin

IPC: H04N7/18 ,  H04N11/02 ,  H04N11/04 ,  H04N19/98 ,  H04N19/50 ,  H04N19/31 ,  H04N19/70 ,  H04N19/33

Abstract: A processor for video coding receives a full-frame rate (FFR) HDR video signal and a corresponding FFR SDR video signal. An encoder generates a scalable bitstream that allows decoders to generate half-frame-rate (HFR) SDR, FFR SDR, HFR HDR, or FFR HDR signals. Given odd and even frames of the input FFR SDR signal, the scalable bitstream combines a base layer of coded even SDR frames with an enhancement layer of coded packed frames, where each packed frame includes a downscaled odd SDR frame, a downscaled even HDR residual frame, and a downscaled odd HDR residual frame. In an alternative implementation, the scalable bitstream combines four signals layers: a base layer of even SDR frames, an enhancement layer of odd SDR frames, a base layer of even HDR residual frames and an enhancement layer of odd HDR residual frames. Corresponding decoder architectures are also presented.

公开(公告)号：US10021390B2

公开(公告)日：2018-07-10

申请号：US15608433

申请日：2017-05-30

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Guan-Ming Su ,  Sheng Qu ,  Hubert Koepfer ,  Yufei Yuan ,  Samir Hulyalkar

IPC: H04N19/15 ,  G06F17/18 ,  H04N19/192 ,  H04N19/98 ,  H04N19/105

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：US09924171B2

公开(公告)日：2018-03-20

申请号：US15280822

申请日：2016-09-29

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Guan-Ming Su ,  Sheng Qu ,  Samir N. Hulyalkar ,  Tao Chen ,  Walter C. Gish ,  Hubert Koepfer

IPC: H04N19/103 ,  H04N19/124 ,  H04N19/98 ,  H04N19/30 ,  H04N19/126

CPC classification number: H04N19/124 ,  H04N19/103 ,  H04N19/126 ,  H04N19/142 ,  H04N19/187 ,  H04N19/30 ,  H04N19/98

Abstract: Techniques use multiple lower bit depth (e.g., 8 bits) codecs to provide higher bit depth (e.g., 12+ bits) high dynamic range images from an upstream device to a downstream device. Multiple layers comprising a base layer and one or more enhancement layers may be used to carry video signals comprising image data compressed by lower bit depth encoders to a downstream device, wherein the base layer cannot be decoded and viewed on its own. Lower bit depth input image data to base layer processing may be generated from higher bit depth high dynamic range input image data via advanced quantization to minimize the volume of image data to be carried by enhancement layer video signals. The image data in the enhancement layer video signals may comprise residual values, quantization parameters, and mapping parameters based in part on a prediction method corresponding to a specific method used in the advanced quantization. Adaptive dynamic range adaptation techniques take into consideration special transition effects, such as fade-in and fade-outs, for improved coding performance.

公开(公告)号：US09866734B2

公开(公告)日：2018-01-09

申请号：US14801633

申请日：2015-07-16

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Seyedalireza Golestaneh ,  Guan-Ming Su

IPC: H04N5/14 ,  G06T7/00 ,  H04N19/30 ,  H04N19/87

CPC classification number: H04N5/147 ,  H04N19/30 ,  H04N19/87

Abstract: A scene change is determined using a first and a second video signal, each representing the same scene or content, but at a different color grade (such as dynamic range). A set of prediction coefficients is generated to generate prediction signals approximating the first signal based on the second signal and a prediction model. A set of prediction error signals is generated based on the prediction signals and the first signal. Then, a scene change is detected based on the characteristics of the prediction error signals. Alternatively, a set of entropy values of the difference signals between the first and second video signals are computed, and a scene change is detected based on the characteristics of the entropy values.

公开(公告)号：US09747673B2

公开(公告)日：2017-08-29

申请号：US14929587

申请日：2015-11-02

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Qing Song ,  Guan-Ming Su ,  Qian Chen

IPC: G06T5/00 ,  G06T5/20 ,  H04N19/30 ,  H04N19/117 ,  H04N19/154 ,  H04N19/182

CPC classification number: G06T5/008 ,  G06T5/002 ,  G06T5/20 ,  G06T2207/10016 ,  G06T2207/20012 ,  G06T2207/20208 ,  H04N19/117 ,  H04N19/154 ,  H04N19/182 ,  H04N19/30

Abstract: A sparse FIR filter can be used to process an image in order to rectify imaging artifacts. In a first example application, the sparse FIR filter is applied as a selective sparse FIR filter that examines a set of selected neighboring pixels of an original pixel in order to identify smooth areas of the image and to selectively apply filtering to only the smooth areas of the image. The parameters of selective filtering are selected based on the characteristics of an inter-layer predictor. In a second example application, the sparse FIR filter is applied as an edge aware selective sparse FIR filter that examines additional neighboring pixels to the set of selected pixels in order to identify edges and carry out selective filtering of smooth areas of the image. Examples for detecting and removing banding artifacts during the coding of high-dynamic range images are provided.

公开(公告)号：US09712834B2

公开(公告)日：2017-07-18

申请号：US14488415

申请日：2014-09-17

Applicant: Dolby Laboratories Licensing Corporation

Inventor： Guan-Ming Su ,  Qian Chen ,  Peng Yin ,  Sheng Qu

IPC: H04N19/33 ,  H04N19/86 ,  H04N19/85

CPC classification number: H04N19/33 ,  H04N19/85 ,  H04N19/86

Abstract: In an embodiment, a control map of false contour filtering is generated for a predicted image. The predicted image is predicted from a low dynamic range image mapped from the wide dynamic range image. Based at least in part on the control map of false contour filtering and the predicted image, one or more filter parameters for a sparse finite-impulse-response (FIR) filter are determined. The sparse FIR filter is applied to filter pixel values in a portion of the predicted image based at least in part on the control map of false contour filtering. The control map of false contour filtering is encoded into a part of a multi-layer video signal that includes the low dynamic range image.