公开(公告)号：US11810266B2

公开(公告)日：2023-11-07

申请号：US17206852

申请日：2021-03-19

Applicant: Apple Inc.

Inventor： Muge Wang ,  Assaf Metuki

IPC: G06T3/40 ,  G06T15/00 ,  G06T7/90

CPC classification number: G06T3/4038 ,  G06T3/4069 ,  G06T7/90 ,  G06T15/005

Abstract: Embodiments relate to generating keypoint descriptors of the keypoints using a sub-scale refinement and a sample pattern radius adjustment. An apparatus includes a sub-pixel refiner circuit and a keypoint descriptor generator circuit. The sub-pixel refiner circuit determines a keypoint scale value for a scale dimension of a keypoint in an image pyramid by performing an interpolation of response map (RM) pixel values of a pixel block of RM images defined around the keypoint. The keypoint descriptor generator circuit determines sample scales of the image pyramid based on the keypoint scale value and determines a radius value for each sample scale based on the keypoint scale value. The keypoint descriptor generator circuit samples patches of pixel values at the sample scales using the radius value for each sample scale to generate a keypoint descriptor of the keypoint.

公开(公告)号：US20230316706A1

公开(公告)日：2023-10-05

申请号：US17693007

申请日：2022-03-11

Applicant: Apple Inc.

Inventor： Assaf Metuki ,  Lukas Polok ,  Danny Gal ,  Liran Fishel

IPC: G06V10/75 ,  G06V10/74

CPC classification number: G06V10/757 ,  G06V10/761

Abstract: Embodiments of the present disclosure relate to selecting a subset of keypoint descriptors of two images for match operation based on their orientation angles indicated in headers of the keypoint descriptors. The keypoint descriptors in the two images are matched by first comparing their headers and then performing vector distance determination. During the header comparison operation, a header of a descriptor of a first image is compared only with headers of keypoint descriptors of a second image in a discrete orientation angle range corresponding to an orientation angle indicated by the header of the first image descriptor or keypoint descriptors of the second image in adjacent discrete orientation angle ranges. After the headers of the keypoint descriptors satisfying one or more matching criteria are determined, distance determination operations are performed between the keypoint descriptors while the remaining keypoint descriptors are discarded without determining their distances.

公开(公告)号：US11475240B2

公开(公告)日：2022-10-18

申请号：US17206901

申请日：2021-03-19

Applicant: Apple Inc.

Inventor： Liran Fishel ,  Assaf Metuki ,  Chuhan Min ,  Wai Yu Trevor Tsang

IPC: G06K9/46 ,  G06K9/62 ,  G06V10/40 ,  G06V10/24 ,  G06V10/75

Abstract: Embodiments relate to generating keypoint descriptors of the keypoints. An apparatus includes a pyramid image generator circuit and a keypoint descriptor generator circuit. The pyramid image generator circuit generates an image pyramid from an input image. The keypoint descriptor generator circuit determines intensity values of sample points in the pyramid images for a keypoint and determines comparison results of comparisons between the intensity values of pairs of the sample points. The keypoint descriptor generator circuit generate bit values defining the comparison results for the keypoint, each bit value corresponding with one of the comparison results, and generate a sequence of the bit values defining an ordering of the comparison results based on importance levels of the comparisons, where the importance level of each comparison defines how much the comparison is representative of features. Bit values for comparisons having the lowest importance levels may be excluded from the sequence.

公开(公告)号：US20220301104A1

公开(公告)日：2022-09-22

申请号：US17206852

申请日：2021-03-19

Applicant: Apple Inc.

Inventor： Muge Wang ,  Assaf Metuki

IPC: G06T3/40 ,  G06T7/90 ,  G06T15/00

Abstract: Embodiments relate to generating keypoint descriptors of the keypoints using a sub-scale refinement and a sample pattern radius adjustment. An apparatus includes a sub-pixel refiner circuit and a keypoint descriptor generator circuit. The sub-pixel refiner circuit determines a keypoint scale value for a scale dimension of a keypoint in an image pyramid by performing an interpolation of response map (RM) pixel values of a pixel block of RM images defined around the keypoint. The keypoint descriptor generator circuit determines sample scales of the image pyramid based on the keypoint scale value and determines a radius value for each sample scale based on the keypoint scale value. The keypoint descriptor generator circuit samples patches of pixel values at the sample scales using the radius value for each sample scale to generate a keypoint descriptor of the keypoint.