US 12,323,589 B2
Method, an image processing device for dividing an array of pixels into slices and tiles, and a system for encoding the slices and tiles into a video stream
Viktor Edpalm, Lund (SE); Song Yuan, Lund (SE); and Toivo Henningsson, Lund (SE)
Assigned to AXIS AB, Lund (SE)
Filed by Axis AB, Lund (SE)
Filed on Dec. 2, 2022, as Appl. No. 18/073,597.
Claims priority of application No. 21216704 (EP), filed on Dec. 22, 2021.
Prior Publication US 2023/0199183 A1, Jun. 22, 2023
Int. Cl. H04N 19/119 (2014.01); H04N 19/174 (2014.01); H04N 19/182 (2014.01); H04N 19/423 (2014.01)
CPC H04N 19/119 (2014.11) [H04N 19/174 (2014.11); H04N 19/182 (2014.11); H04N 19/423 (2014.11)] 13 Claims
OG exemplary drawing
 
1. A method for dividing an array of pixels into slices and tiles for encoding the array of pixels into an encoded video stream by means of a first encoder arranged in a first image processing circuitry and a second encoder arranged in a second image processing circuitry, wherein pixels of the array of pixels are arranged at regular intervals along a vertical direction and a horizontal direction, wherein each slice is separated by a straight horizontal line over the full width from the respective adjacent slices and is encoded without the need for access to image data relating to other slices and each tile is separated by a vertical straight line over the full height of a slice from respective adjacent tiles in the same slice and is encoded without the need for access to image data relating to other tiles, wherein the array of pixels consists of a first subset of pixels having pixel data stored in a first buffer arranged in the first image processing circuitry and a second subset of pixels having pixel data stored in a second buffer arranged in the second image processing circuitry, wherein a first border between the first subset of pixels and the second subset of pixels is tilted at a tilt angle in relation to the array of pixels, the method comprising:
dividing the array of pixels into two or more slices; and
dividing each slice into two or more tiles, wherein the two or more tiles of each slice consists of a first subset of tiles and a second subset of tiles, wherein the first subset of tiles and the second subset of tiles are disjunct and the first subset of tiles is to be encoded by the first encoder and the second subset of tiles is to be encoded by the second encoder,
wherein the act of dividing each slice into two or more tiles comprises setting a second border between the first subset of tiles and the second subset of tiles at an offset along the horizontal direction between two adjacent slices of the two or more slices such that the second border between the first subset of tiles and the second subset of tiles in two adjacent slices are not aligned along the horizontal direction, wherein the offset is based on the tilt angle such that the number of pixels to be encoded into the first subset of tiles of each slice that have pixel data stored in the second buffer plus the number of pixels to be encoded into the second subset of tiles of each slice that have pixel data stored in the first buffer is reduced in relation to not using an offset, and
wherein the method further comprises:
transferring, from the second buffer to the first encoder, pixel data of pixels to be encoded into the first subset of tiles of each slice having pixel data stored in the second buffer;
encoding the first subset of tiles by means of the first encoder;
transferring, from the first buffer to the second encoder, pixel data of pixels to be encoded into the second subset of tiles of each slice having pixel data stored in the first buffer; and
encoding the second subset of tiles by means of the second encoder.