公开(公告)号：US11620768B2

公开(公告)日：2023-04-04

申请号：US17355830

申请日：2021-06-23

Applicant: Apple Inc.

Inventor： David Flynn

IPC: G06T9/40 ,  G06T15/10

Abstract: An encoder is configured to compress point cloud geometry information using an octree geometric compression technique that utilizes node groups. Nodes within a node group are scanned according to a breadth first scan order. Sequential node groups to evaluate may be selected according to a breadth first scan order or a depth first scan order based on whether or not the breadth first scan order or the depth first scan order is indicated in a flag in a preceding node group evaluated. In some embodiments, evaluation orders for node groups may be implicit without being signaled via flags. A decoder is configured to reconstruct a point cloud based on a bit stream encoded by the encoder.

公开(公告)号：US11615557B2

公开(公告)日：2023-03-28

申请号：US17355819

申请日：2021-06-23

Applicant: Apple Inc.

Inventor： David Flynn

IPC: G06T9/40 ,  G06T15/10

Abstract: An encoder is configured to compress point cloud geometry information using an octree geometric compression technique that utilizes slices corresponding in size to data transmission units. In some embodiments, a subsequent slice may be set to use a re-set entropy context or may be set to use an entropy context saved for a preceding slice. In some embodiments, an entropy context for the preceding slice may be for a slice other than the immediately preceding slice of the subsequent slice being evaluated, such that if the immediately preceding slice is lost in transmission (or if the immediately preceding slice and the subsequent slice are being evaluated in parallel) the subsequent slice's entropy context can still be determined without depending on the immediately preceding slice. A decoder is configured to reconstruct a point cloud based on a bit stream encoded by the encoder.

公开(公告)号：US20230053544A1

公开(公告)日：2023-02-23

申请号：US17791692

申请日：2021-01-08

Applicant: APPLE INC.

Inventor： David Flynn ,  Khaled Mammou ,  Fabrice A. Robinet

IPC: G06T9/40 ,  G06T17/00

Abstract: An example method includes receiving (502) a plurality of points that represent a point cloud; representing a position of the point in each dimension of a three-dimensional space as a sequence of bits (504), where the position of the point is encoded according to a tree data structure; partitioning (506) at least one of the sequences of bits into a first portion of bits and a second portion of bits; quantizing (508) each of the second portions of bits according to a quantization step size, where the quantization step size is determined according to an exponential function having a quantization parameter value as an input and the quantization step size as an output; and generating (510) a data structure representing the point cloud and including the quantized second portions of bits.

公开(公告)号：US20230046917A1

公开(公告)日：2023-02-16

申请号：US17791635

申请日：2021-01-08

Applicant: APPLE INC.

Inventor： David Flynn ,  Khaled Mammou ,  Fabrice A. Robinet

IPC: H04N19/597 ,  H04N19/96 ,  H04N19/124 ,  H04N19/167 ,  H04N19/182 ,  G06T15/00

Abstract: An example device includes one or more processors, and memory storing instructions that when executed by the processors, cause the processors to receive points that represent a point cloud in three-dimensional space, and generate a data structure representing the point cloud. Generating the data structure includes encoding a position of each point in each dimension as a sequence of bits according to a tree data structure; partitioning each of the sequences into two or more portions according to a scaling depth; determining that a subset of the points is spatially isolated from a remainder of the points; quantizing each of the portions associated with the subset of the points according to a first quantization step size; quantizing each of the portions associated with the remainder of the points according to a second quantization step size; and including the quantized portions in the data structure.

公开(公告)号：US20220405533A1

公开(公告)日：2022-12-22

申请号：US17817920

申请日：2022-08-05

Applicant: Apple Inc.

Inventor： Khaled Mammou ,  Alexandros Tourapis ,  David Flynn ,  Zhenzhen Gao

IPC: G06K9/62 ,  G06T7/70 ,  G06T11/20

Abstract: A search space for performing nearest neighbor searches for encoding point cloud data may be trimmed. Ranges of a space filling curve may be used to identify search space to exclude or reuse, instead of generating nearest neighbor search results for at least some of the points of a point cloud located within some of the ranges of the space filling curve. Additionally, neighboring voxels may be searched to identify any neighboring points missed during the trimmed search based on the ranges of the space filling curve.