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：US10902601B2

公开(公告)日：2021-01-26

申请号：US16462496

申请日：2018-01-16

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： Neeraj J. Gadgil ,  Yee Jin Lee ,  Qian Chen ,  Guan-Ming Su

IPC: G06T7/11 ,  G06T7/143 ,  G06T7/136 ,  G06T7/174 ,  G06T9/00 ,  G06T5/00 ,  G06T5/40 ,  G06T5/50 ,  G06T3/40 ,  G06T7/50 ,  H04N19/186 ,  H04N19/98 ,  H04N19/87 ,  H04N19/30

Abstract: Given a standard-dynamic range (SDR) video input, techniques for generating and compressing composer metadata describing inverse luma and chroma reshaping functions are described. Given the SDR input, the composer metadata allow a decoder to generate a corresponding output in high-dynamic range. Three techniques are proposed: a static, sequence-based, architecture, a two-stage, scene-based, distributed solution with a centralized post-processing method, and a single-stage distributed solution using overlapped segments. Techniques to reduce the amount of transmitted composer metadata are also described.

公开(公告)号：US20190110054A1

公开(公告)日：2019-04-11

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 ,  H04N19/187 ,  H04N19/102 ,  H04N1/60 ,  H04N19/44

CPC classification number: H04N19/186 ,  G06T5/008 ,  H04N1/6027 ,  H04N1/6058 ,  H04N1/648 ,  H04N19/102 ,  H04N19/117 ,  H04N19/154 ,  H04N19/176 ,  H04N19/187 ,  H04N19/44 ,  H04N19/80 ,  H04N19/85 ,  H04N2201/3256

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.