公开(公告)号：US08897580B2

公开(公告)日：2014-11-25

申请号：US13664359

申请日：2012-10-30

Applicant: Apple Inc.

Inventor： Yeping Su ,  Jiefu Zhai ,  James Oliver Normile ,  Hsi-Jung Wu ,  Hao Pan

IPC: G06K9/36

CPC classification number: G09G3/2048 ,  G09G3/2066 ,  G09G2340/06 ,  G09G2350/00

Abstract: YCbCr image data may be dithered and converted into RGB data shown on a 8-bit or other bit display. Dither methods and image processors are provided which generate the banding artifact free image data during this process. Some methods and image processors may applying a stronger dither having a same mean with a larger variance to the image data before it is converted to RGB data. Others methods and image processors may calculate a quantization or encoding error and diffuse the calculated error among one or more neighboring pixel blocks.

Abstract translation: YCbCr图像数据可以抖动并转换成8位或其他位显示器上显示的RGB数据。 提供抖动方法和图像处理器，其在该处理期间产生无带纹带图像数据。 一些方法和图像处理器可以在将图像数据转换成RGB数据之前，对图像数据应用具有相同平均值的较强抖动。 其他方法和图像处理器可以计算量化或编码误差并且在一个或多个相邻像素块之间扩展所计算的误差。

公开(公告)号：US11818394B2

公开(公告)日：2023-11-14

申请号：US17207267

申请日：2021-03-19

Applicant: Apple Inc.

Inventor： Jae Hoon Kim ,  Xiaosong Zhou ,  Dazhong Zhang ,  Hang Yuan ,  Jiefu Zhai ,  Chris Y. Chung ,  Hsi-Jung Wu

IPC: H04N19/176 ,  H04N19/105 ,  H04N19/597 ,  H04N19/547

CPC classification number: H04N19/597 ,  H04N19/105 ,  H04N19/176 ,  H04N19/547

Abstract: Techniques are disclosed for coding video data predictively based on predictions made from spherical-domain projections of input pictures to be coded and reference pictures that are prediction candidates. Spherical projection of an input picture and the candidate reference pictures may be generated. Thereafter, a search may be conducted for a match between the spherical-domain representation of a pixel block to be coded and a spherical-domain representation of the reference picture. On a match, an offset may be determined between the spherical-domain representation of the pixel block to a matching portion of the of the reference picture in the spherical-domain representation. The spherical-domain offset may be transformed to a motion vector in a source-domain representation of the input picture, and the pixel block may be coded predictively with reference to a source-domain representation of the matching portion of the reference picture.

公开(公告)号：US11627343B2

公开(公告)日：2023-04-11

申请号：US17188473

申请日：2021-03-01

Applicant: Apple Inc.

Inventor： Xiaohua Yang ,  Alexandros Tourapis ,  Dazhong Zhang ,  Hang Yuan ,  Hsi-Jung Wu ,  Jae Hoon Kim ,  Jiefu Zhai ,  Ming Chen ,  Xiaosong Zhou

IPC: H04N19/52 ,  H04N19/90 ,  H04N19/597 ,  H04N21/2343 ,  G06F3/01

Abstract: In communication applications, aggregate source image data at a transmitter exceeds the data that is needed to display a rendering of a viewport at a receiver. Improved streaming techniques that include estimating a location of a viewport at a future time. According to such techniques, the viewport may represent a portion of an image from a multi-directional video to be displayed at the future time, and tile(s) of the image may be identified in which the viewport is estimated to be located. In these techniques, the image data of tile(s) in which the viewport is estimated to be located may be requested at a first service tier, and the other tile in which the viewport is not estimated to be located may be requested at a second service tier, lower than the first service tier.

公开(公告)号：US20210227236A1

公开(公告)日：2021-07-22

申请号：US17221299

申请日：2021-04-02

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Dazhong Zhang ,  Hang Yuan ,  Hsi-Jung Wu ,  Jae Hoon Kim ,  Jiefu Zhai ,  Ming Chen ,  Xiaosong Zhou

IPC: H04N19/29 ,  H04N19/103 ,  G09G5/14 ,  H04N21/44

Abstract: Aspects of the present disclosure provide techniques for reducing latency and improving image quality of a viewport extracted from multi-directional video communications. According to such techniques, first streams of coded video data are received from a source. The first streams include coded data for each of a plurality of tiles representing a multi-directional video, where each tile corresponding to a predetermined spatial region of the multi-directional video, and at least one tile of the plurality of tiles in the first streams contains a current viewport location at a receiver. The techniques include decoding the first streams and displaying the tile containing the current viewport location. When the viewport location at the receiver changes to include a new tile of the plurality of tiles, retrieving and decoding first streams for the new tile, displaying the decoded content for the changed viewport location, and transmitting the changed viewport location to the source.

公开(公告)号：US10939139B2

公开(公告)日：2021-03-02

申请号：US16204792

申请日：2018-11-29

Applicant: Apple Inc.

Inventor： Xiaohua Yang ,  Alexandros Tourapis ,  Dazhong Zhang ,  Hang Yuan ,  Hsi-Jung Wu ,  Jae Hoon Kim ,  Jiefu Zhai ,  Ming Chen ,  Xiaosong Zhou

IPC: H04N19/52 ,  H04N19/90 ,  H04N19/597 ,  H04N21/2343 ,  G06F3/01

Abstract: In communication applications, aggregate source image data at a transmitter exceeds the data that is needed to display a rendering of a viewport at a receiver. Improved streaming techniques that include estimating a location of a viewport at a future time. According to such techniques, the viewport may represent a portion of an image from a multi-directional video to be displayed at the future time, and tile(s) of the image may be identified in which the viewport is estimated to be located. In these techniques, the image data of tile(s) in which the viewport is estimated to be located may be requested at a first service tier, and the other tile in which the viewport is not estimated to be located may be requested at a second service tier, lower than the first service tier.

公开(公告)号：US20200296426A1

公开(公告)日：2020-09-17

申请号：US16890245

申请日：2020-06-02

Applicant: Apple Inc.

Inventor： Jiefu Zhai ,  Dazhong Zhang ,  Xiaosong Zhou ,  Chris Y. Chung ,  Hsi-Jung Wu ,  Peikang Song ,  David R. Conrad ,  Jae Hoon Kim ,  Yunfei Zheng

IPC: H04N19/82 ,  H04N19/186

Abstract: Chroma deblock filtering of reconstructed video samples may be performed to remove blockiness artifacts and reduce color artifacts without over-smoothing. In a first method, chroma deblocking may be performed for boundary samples of a smallest transform size, regardless of partitions and coding modes. In a second method, chroma deblocking may be performed when a boundary strength is greater than 0. In a third method, chroma deblocking may be performed regardless of boundary strengths. In a fourth method, the type of chroma deblocking to be performed may be signaled in a slice header by a flag. Furthermore, luma deblock filtering techniques may be applied to chroma deblock filtering.

公开(公告)号：US10708623B2

公开(公告)日：2020-07-07

申请号：US16050744

申请日：2018-07-31

Applicant: Apple Inc.

Inventor： Jiefu Zhai ,  Dazhong Zhang ,  Xiaosong Zhou ,  Chris Y. Chung ,  Hsi-Jung Wu ,  Peikang Song ,  David R. Conrad ,  Jae Hoon Kim ,  Yunfei Zheng

IPC: H04N19/82 ,  H04N19/186

Abstract: Chroma deblock filtering of reconstructed video samples may be performed to remove blockiness artifacts and reduce color artifacts without over-smoothing. In a first method, chroma deblocking may be performed for boundary samples of a smallest transform size, regardless of partitions and coding modes. In a second method, chroma deblocking may be performed when a boundary strength is greater than 0. In a third method, chroma deblocking may be performed regardless of boundary strengths. In a fourth method, the type of chroma deblocking to be performed may be signaled in a slice header by a flag. Furthermore, luma deblock filtering techniques may be applied to chroma deblock filtering.

公开(公告)号：US20200092571A1

公开(公告)日：2020-03-19

申请号：US16132219

申请日：2018-09-14

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Dazhong Zhang ,  Hang Yuan ,  Hsi-Jung Wu ,  Jae Hoon Kim ,  Jiefu Zhai ,  Ming Chen ,  Xiaosong Zhou

IPC: H04N19/29 ,  H04N21/44 ,  G09G5/14 ,  H04N19/103

Abstract: Aspects of the present disclosure provide techniques for reducing latency and improving image quality of a viewport extracted from multi-directional video communications. According to such techniques, first streams of coded video data are received from a source. The first streams include coded data for each of a plurality of tiles representing a multi-directional video, where each tile corresponding to a predetermined spatial region of the multi-directional video, and at least one tile of the plurality of tiles in the first streams contains a current viewport location at a receiver. The techniques include decoding the first streams and displaying the tile containing the current viewport location. When the viewport location at the receiver changes to include a new tile of the plurality of tiles, retrieving and decoding first streams for the new tile, displaying the decoded content for the changed viewport location, and transmitting the changed viewport location to the source.

公开(公告)号：US10402677B2

公开(公告)日：2019-09-03

申请号：US15618909

申请日：2017-06-09

Applicant: Apple Inc.

Inventor： Jiefu Zhai ,  Ke Zhang ,  Yunfei Zheng ,  Shujie Liu ,  Albert Keinath ,  Xiaosong Zhou ,  Chris Chung ,  Hsi-Jung Wu

IPC: G06K9/00 ,  G06K9/46 ,  G06K9/62

Abstract: Techniques are disclosed for estimating quality of images in an automated fashion. According to these techniques, a source image may be downsampled to generate at least two downsampled images at different levels of downsampling. Blurriness of the images may be estimated starting with a most-heavily downsampled image. Blocks of a given image may be evaluated for blurriness and, when a block of a given image is estimated to be blurry, the block of the image and co-located blocks of higher resolution image(s) may be designated as blurry. Thereafter, a blurriness score may be calculated for the source image from the number of blocks of the source image designated as blurry.

公开(公告)号：US10402226B2

公开(公告)日：2019-09-03

申请号：US15173047

申请日：2016-06-03

Applicant: Apple Inc.

Inventor： Albert Keinath ,  Ke Zhang ,  Yunfei Zheng ,  Shujie Liu ,  Jiefu Zhai ,  Chris Y. Chung ,  Xiaosong Zhou ,  Hsi-Jung Wu

IPC: G06F9/46 ,  G06F9/50 ,  G06F9/48 ,  H04L29/08 ,  H04N21/443 ,  H04N21/414

Abstract: A system for processing media on a resource restricted device, the system including a memory to store data representing media assets and associated descriptors, and program instructions representing an application and a media processing system, and a processor to execute the program instructions, wherein the program instructions represent the media processing system, in response to a call from an application defining a plurality of services to be performed on an asset, determine a tiered schedule of processing operations to be performed upon the asset based on a processing budget associated therewith, and iteratively execute the processing operations on a tier-by-tier basis, unless interrupted.