公开(公告)号：WO2020033573A1

公开(公告)日：2020-02-13

申请号：PCT/US2019/045541

申请日：2019-08-07

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： GADGIL, Neeraj J. ,  SU, Guan-Ming ,  ZHU, Qiang ,  SONG, Qing

IPC: H04N19/117 ,  H04N19/98

Abstract: Methods and systems for reducing banding artifacts when displaying high-dynamic-range images are described. Given an input image in a first dynamic range, and an input backward reshaping function mapping codewords from the first dynamic range to a second dynamic range, wherein the second dynamic range is equal or higher than the first dynamic range, statistical data based on the input image and the input backward reshaping function are generated to estimate the risk of banding artifacts in a target image in the second dynamic range generated by applying the input backward reshaping function to the input image. Separate banding alleviation algorithms are applied in the darks and highlights parts of the first dynamic range to generate a modified backward reshaping function, which when applied to the input image to generate the target image eliminates or reduces banding in the target image.

公开(公告)号：WO2018202744A1

公开(公告)日：2018-11-08

申请号：PCT/EP2018/061280

申请日：2018-05-03

Applicant: KONINKLIJKE PHILIPS N.V.

Inventor： TICHELAAR, Johannes Yzebrand ,  MERTENS, Mark Jozef Willem ,  VAN MOURIK, Johannes Gerardus Rijk

IPC: G06T5/00 ,  H04N19/85 ,  H04N19/98

Abstract: To enable better color and in particular color saturation control for HDR image handling systems which need to do luminance dynamic range conversion, e.g. from a SDR image to an image optimized for rendering on a display of higher display peak brightness and dynamic range, the inventors invented an apparatus (400) for processing a color saturation (C'bL, C'rL) of an input color (Y'L, C'bL, C'rL) of an input image (Im RLDR) to yield an output color (Y'M, Cb'M, Cr'M) of an output image (Im3000nit) corresponding to the input image, which output image is a re-grading of the input image characterized by the fact that its pixel colors have a different normalized luminance position (Y2) compared to the normalized luminance positions of the input colors (Yl), the normalized luminances being defined as the luminance of a pixel divided by the respective maximal codeable luminance of the image's luminance representation, whereby the ratio of the maximum codeable luminance of the input image and the maximum codeable luminance of the output image is at least 4 or larger, or 1/4 th or smaller, the apparatus comprising a luminance processor (401) arranged to apply a display tuned luminance mapping function (F_L_da) to determine an output luminance (Y'M) from the input luminance (Y'L) of the input color, the apparatus further comprising a saturation factor determination unit (402) arranged to calculate a final saturation processing strategy (b; Bcorr) based on an initial saturation processing strategy (F _sat) and based on a secondary luminance value (Y'_H) which is derivable from the output luminance (Y'M) by applying a luminance mapping function (F M2H) which is based on the luminance mapping function (F_L_s2h).

公开(公告)号：WO2018153800A1

公开(公告)日：2018-08-30

申请号：PCT/EP2018/053984

申请日：2018-02-19

Applicant: THOMSON LICENSING

Inventor： ANDRIVON, Pierre ,  FRANCOIS, Edouard ,  OLIVIER, Yannick ,  TOUZE, David

IPC: H04N19/46 ,  H04N19/30 ,  H04N19/186 ,  H04N19/98

Abstract: The present principles relates to a method and device for reconstructing an HDR image by applying a reconstruction process on a SDR image whose the content is similar to the content of the HDR image but the dynamic range of the luminance values of said SDR image is lower than the dynamic range of the luminance values of said HDR image, said reconstruction process requiring parameters obtained from a bitstream. The method is characterized in that the method further comprises determining whether all the required parameters are available from the bitstream and recovering the lost or corrupted parameters from additional data, said reconstruction process further taking into account said recovered parameters.

公开(公告)号：WO2017114016A1

公开(公告)日：2017-07-06

申请号：PCT/CN2016/105926

申请日：2016-11-15

Applicant: 中兴通讯股份有限公司

Inventor： 李明 ,  吴平 ,  吴钊 ,  尚国强

IPC: H04N19/44 ,  H04N19/30 ,  H04N19/98

CPC classification number: H04N19/30 ,  H04N19/44 ,  H04N19/98

Abstract: 本发明提供了一种图像解码和编码方法、解码和编码装置、解码器及编码器，其中，该图像解码方法包括：解析视频码流，从该视频码流的图像和/或分片层数据单元中获取整形参数，并根据获取的整形参数确定恢复图像使用的整形参数；使用上述恢复图像使用的整形参数对恢复图像进行整形处理；其中，该恢复图像是在执行整形处理前，解码视频码流获得的图像；上述图像和/或分片层数据单元包括如下数据单元至少之一：不同于图像参数集PPS的图像和/或分片层参数集，上述恢复图像对应的接入单元AU中包括的参数数据单元，分片头信息，系统层图像参数数据单元。通过本发明，解决了相关技术中存在的视频观看质量差，整形参数的编码开销大的问题。

公开(公告)号：WO2017024042A3

公开(公告)日：2017-03-09

申请号：PCT/US2016045362

申请日：2016-08-03

Applicant: DOLBY LABORATORIES LICENSING CORP

Inventor： ATKINS ROBIN ,  YIN PENG ,  LU TAORAN ,  PUTLARZ JACLYN ANNE

IPC: H04N19/46 ,  H04N19/117 ,  H04N19/186 ,  H04N19/85 ,  H04N19/98

CPC classification number: H04N19/85 ,  G09G2340/06 ,  H04N19/46 ,  H04N19/98

Abstract: In a method to improve backwards compatibility when decoding high-dynamic range images coded in a wide color gamut (WCG) space which may not be compatible with legacy color spaces, hue and/or saturation values of images in an image database are computed for both a legacy color space (say, YCbCr-gamma) and a preferred WCG color space (say, IPT-PQ). Based on a cost function, a reshaped color space is computed so that the distance between the hue values in the legacy color space and rotated hue values in the preferred color space is minimized. HDR images are coded in the reshaped color space. Legacy devices can still decode standard dynamic range images assuming they are coded in the legacy color space, while updated devices can use color reshaping information to decode HDR images in the preferred color space at full dynamic range.

Abstract translation: 在对可能与传统色彩空间不兼容的宽色域（WCG）空间中编码的高动态范围图像进行解码时改善向后兼容性的方法中，计算图像数据库中图像的色调和/或饱和度值 传统色彩空间（比如YCbCr-gamma）和优选的WCG色彩空间（比如说IPT-PQ）。 基于成本函数，计算重塑的颜色空间，使得传统颜色空间中的色调值与优选颜色空间中旋转的色调值之间的距离最小化。 HDR图像在重新变形的色彩空间中编码。 传统设备仍然可以解码标准动态范围图像，假设它们在传统色彩空间中编码，而更新的设备可以使用色彩整形信息在全动态范围内解码首选色彩空间中的HDR图像。

公开(公告)号：WO2017003525A1

公开(公告)日：2017-01-05

申请号：PCT/US2016/020232

申请日：2016-03-01

Applicant: DOLBY LABORATORIES LICENSING CORPORATION

Inventor： SU, Guan-Ming

IPC: H04N19/136 ,  H04N19/98

CPC classification number: H04N19/124 ,  H04N19/136 ,  H04N19/186 ,  H04N19/98

Abstract: Noise levels in pre-reshaped codewords of a pre-reshaped bit depth in pre-reshaped images within a time window of a scene are calculated. Per-bin minimal bit depth values are computed for pre-reshaped codeword bins based on the calculated noise levels in the pre-reshaped codewords. Each per-bin minimal bit depth value corresponds to a minimal bit depth value for a respective pre-reshaped codeword bin. A specific codeword mapping function for a specific pre-reshaped image in the pre-reshaped image is generated based on the pre-reshaped bit depth, the per-bin minimal bit depth values, and a target bit depth smaller than the pre-reshaped bit depth. The specific codeword mapping function is applied to specific pre-reshaped codewords of the specific pre-reshaped image to generate specific target codewords of the target bit depth for a specific output image.

Abstract translation: 计算在场景的时间窗内的预重组图像中的预重新形成的位深度的预重新定标码字中的噪声水平。 基于预重新定标码字中计算出的噪声电平，为预重新形成的码字箱计算每位最小位深度值。 每个每个最小位深度值对应于相应的预重新形成的码字仓的最小位深度值。 基于预重新形成的比特深度，每个最小比特深度值和比预分解比特的目标比特深度生成用于预重新映像的特定预重新映像的特定码字映射功能 深度。 特定码字映射函数被应用于特定预重新映象图像的特定预重新映射码字，以产生特定输出图像的目标比特深度的特定目标码字。

公开(公告)号：WO2016197033A1

公开(公告)日：2016-12-08

申请号：PCT/US2016/035875

申请日：2016-06-03

Applicant: APPLE INC.

Inventor： HENDRY, Ian C. ,  GREENEBAUM, Kenneth I. ,  DACQUAY, Eric L.

IPC: H04N5/202 ,  H04N5/57 ,  H04N19/46 ,  H04N19/98 ,  G09G5/02 ,  H04N1/60

CPC classification number: G09G5/10 ,  G06F3/04847 ,  G06T1/20 ,  G06T11/001 ,  G06T2200/24 ,  G09G5/02 ,  G09G2320/0626 ,  G09G2320/066 ,  G09G2340/06 ,  G09G2354/00 ,  G09G2360/144 ,  H04N1/6061 ,  H04N1/6088 ,  H04N5/202 ,  H04N5/58 ,  H04N19/46 ,  H04N19/98

Abstract: Methods and apparatus for rendering and displaying high dynamic range (HDR) digital image content. An HDR rendering and display system may support the rendering and display of standard dynamic range (SDR) and HDR content to both HDR-enabled and standard displays. The HDR rendering and display system renders digital image content into the HDR space and maps the rendered HDR content into the display space of HDR or standard displays using display processing techniques that may preserve at least some of the HDR content even for standard displays. The HDR rendering and display system may take into account various information including but not limited to display characteristics such as size, control inputs, current image characteristics such as image brightness, and environmental information such as viewer position and ambient lighting levels to dynamically adapt the rendering and display of the digital image content according to ambient viewing conditions at the target display.

Abstract translation: 用于渲染和显示高动态范围（HDR）数字图像内容的方法和装置。 HDR渲染和显示系统可以支持标准动态范围（SDR）和HDR内容的渲染和显示，以支持HDR和标准显示。 HDR渲染和显示系统将数字图像内容呈现到HDR空间中，并且使用显示处理技术将所渲染的HDR内容映射到HDR或标准显示器的显示空间中，即使对于标准显示也可以保留HDR内容中的至少一些。 HDR渲染和显示系统可以考虑各种信息，包括但不限于诸如尺寸，控制输入，诸如图像亮度的当前图像特性等显示特性，以及诸如观看者位置和环境照明水平的环境信息，以动态地适应渲染 以及根据目标显示器上的环境观看条件显示数字图像内容。

公开(公告)号：WO2016055178A1

公开(公告)日：2016-04-14

申请号：PCT/EP2015/066294

申请日：2015-07-16

Applicant: KONINKLIJKE PHILIPS N.V.

Inventor： STESSEN, Jeroen Hubert Christoffel Jacobus

IPC: H04N1/60 ,  H04N9/68 ,  G06T5/00 ,  H04N19/98

CPC classification number: H04N19/186 ,  G06T5/009 ,  G06T2207/20208 ,  H04N1/6027 ,  H04N9/68 ,  H04N19/85 ,  H04N19/98

Abstract: Because we needed a new color saturation processing in tune with dynamic range transformations necessary for handling the recently introduced high dynamic range image encoding, we describe a color saturation modification apparatus (101) arranged to determine linear color differences (R-Y,G-Y,B-Y) on the basis of an input color (R,G,B) and a luminance (Y) of the input color, and to do a multiplication of the linear color differences (R-Y,G-Y,B-Y) with a gain (g), characterized in that the apparatus is arranged to determine the gain as a function of a difference value (V_in-Y) being defined as the value of the highest one of the linear color differences (R-Y,G-Y,B-Y).

Abstract translation: 因为我们需要一个新的色彩饱和度处理，以适应处理最近引入的高动态范围图像编码所需的动态范围变换，所以我们描述了一种色彩饱和度修正装置（101），用于确定线性色差（RY，GY，BY） 输入颜色的输入颜色（R，G，B）和亮度（Y）的基础，并且将线性色差（RY，GY，BY）与增益（g）进行乘法，其特征在于 该装置被设置为根据作为线性色差（RY，GY，BY）中最高的一个的值被定义为差值（V_in-Y）的函数来确定增益。

公开(公告)号：WO2015193117A1

公开(公告)日：2015-12-23

申请号：PCT/EP2015/062477

申请日：2015-06-04

Applicant: THOMSON LICENSING

Inventor： ANDRIVON, Pierre ,  LASSERRE, Sebastien ,  FRANCOIS, Edouard

IPC: G06T5/00 ,  H04N19/44 ,  H04N19/98 ,  H04N19/127 ,  H04N19/186

CPC classification number: H04N19/127 ,  H04N19/186 ,  H04N19/44 ,  H04N19/98

Abstract: The present disclosure generally relates to a method and device for decoding an HDR picture from a bitstream representing a LDR picture and an illumination picture. The method comprising: - obtaining a decoded version of the HDR picture by multiplying the sample values of a decoded version of the LDR picture by the sample values of the decoded version of the illumination picture; and - obtaining a color value expressed in an output color space for each sample value of the decoded version of the HDR picture, the method is characterized in that it further comprises: - obtaining a color value expressed in the output color space for each sample value of a decoded version of the LDR picture just before multiplying said color values by the sample values of the decoded version of the illumination picture.

Abstract translation: 本公开一般涉及用于从表示LDR图像和照明图像的比特流中解码HDR图像的方法和装置。 该方法包括：通过将LDR图像的解码版本的采样值乘以照明图像的解码版本的采样值，获得HDR图像的解码版本; 以及 - 获得针对HDR图像的解码版本的每个样本值在输出颜色空间中表示的颜色值，其特征在于，还包括： - 获得在每个样本值的输出颜色空间中表示的颜色值 在将所述颜色值乘以照明图像的解码版本的采样值之前的LDR图像的解码版本。

公开(公告)号：WO2022076125A1

公开(公告)日：2022-04-14

申请号：PCT/US2021/049697

申请日：2021-09-09

Applicant: QUALCOMM INCORPORATED

Inventor： LI, Min ,  IKIZYAN, Ike ,  KOTTILINGAL, Sudeep Ravi ,  ANDANDAN, Gopikrishnaiah

IPC: H04N19/136 ,  H04N19/98 ,  G06F3/14 ,  G09G5/00 ,  G09G5/10 ,  G06T5/00 ,  G06T5/40 ,  H04N1/407 ,  G06T5/50 ,  H04N19/154

Abstract: The present disclosure relates to methods and devices for video or frame processing including an apparatus, e.g., a video or frame processor. In some aspects, the apparatus may receive a video stream including a plurality of frames, each of the plurality of frames including luminance information. The apparatus may also perform a histogram analysis on the luminance information for each of the plurality of frames. Additionally, the apparatus may determine whether a difference between the luminance information for each of the plurality of frames and a current luminance distribution is greater than a perceptual threshold. The apparatus may also calculate an updated tone mapping configuration based on the luminance information for a frame when the difference between the luminance information for the frame and the current luminance distribution is greater than the perceptual threshold.