公开(公告)号：US20250113046A1

公开(公告)日：2025-04-03

申请号：US18899847

申请日：2024-09-27

Applicant: Axis AB

Inventor： Malte JOHANSSON ,  Axel Jonsson ,  Mattias Pettersson

IPC: H04N19/164 ,  H04N19/176 ,  H04N19/503

Abstract: A system for handling bandwidth shortage for transmission of encoded video frames. In a sending device, a long term reference frame which indicates bandwidth shortage is created. During a first time period, the reference frame is sent to the receiving device for storage. During a subsequent second time period, bandwidth shortage is determined in the sending device, wherein the bandwidth during the second time period is insufficient if the encoded video frames are encoded according to an encoding principle used at times without bandwidth shortage. During the second time period, inter encoded frames referencing the long term reference frame are sent, wherein each frame includes encoded blocks, and at least a subset of the blocks of the inter encoded frames are empty blocks such that the bit rate of the inter encoded frames is lower or equal to the bandwidth during the second time period.

公开(公告)号：US12120421B2

公开(公告)日：2024-10-15

申请号：US17570774

申请日：2022-01-07

Applicant: Axis AB

Inventor： Axel Keskikangas ,  Viktor Edpalm ,  Mattias Pettersson

IPC: H04N23/65 ,  G06T5/00 ,  G06V20/40 ,  G11B20/10 ,  G11B27/028

CPC classification number: H04N23/651 ,  G06T5/00 ,  G06V20/44 ,  G11B20/10527 ,  G11B27/028 ,  G11B2020/10712

Abstract: A method of providing an event-initiated video sequence, comprises a pre-event video sequence and a post-event video sequence. The pre-event image frames are stored in a non-processed format until such time that an event is taking place. By postponing the image processing of the pre-event video sequence, power savings are accomplished.

公开(公告)号：US20210201639A1

公开(公告)日：2021-07-01

申请号：US16729985

申请日：2019-12-30

Applicant: Axis AB

Inventor： Mattias Pettersson

IPC: G08B13/196 ,  H04N21/2187 ,  H04N21/24 ,  H04N21/2662

Abstract: A method may include transmitting a video stream of a live scene over a network at a real-time transmission speed and detecting an event associated with the video stream being transmitted. The method may include transmitting the video stream over the network at a speed lower than the real-time transmission speed during the event. Transmitting the video stream at the speed lower than the real-time transmission speed may introduce a time stretch for the video stream to be played in slow motion. The method may include reducing a bitrate of the video stream after the event and transmitting the video stream with the reduced bitrate over the network after the event to compensate for the time stretch.

公开(公告)号：US12278970B2

公开(公告)日：2025-04-15

申请号：US17942592

申请日：2022-09-12

Applicant: Axis AB

Inventor： Mattias Pettersson ,  Björn Völcker ,  Malte Johansson

IPC: H04N19/15 ,  H04N19/107 ,  H04N19/136 ,  H04N19/177 ,  H04N19/184 ,  H04N19/423

Abstract: A computer implemented method for controlling a transmission of a video stream is provided. The method comprises estimating a number of bits for a group of pictures, GOP, of the video stream to be transmitted, setting a latency requirement for the transmission of the video stream, determining an average minimum video bitrate across the GOP based on the estimated number of bits and a time corresponding to a time period represented by a duration of the GOP, for video frames in the GOP setting an output bitrate for transmission of a video frame based on the latency requirement and the average minimum video bitrate, and transmitting the video frame using the output bitrate.

公开(公告)号：US11716475B2

公开(公告)日：2023-08-01

申请号：US17499887

申请日：2021-10-13

Applicant: Axis AB

Inventor： Fredrik Pihl ,  Mattias Pettersson

IPC: H04N19/132 ,  H04N19/146 ,  H04N19/172 ,  H04N19/59

CPC classification number: H04N19/132 ,  H04N19/146 ,  H04N19/172 ,  H04N19/59

Abstract: An image processing device 300, a non-transitory computer readable storage medium, a monitoring camera 200 and a method 100 of pre-processing images of a video stream before encoding the video stream are disclosed. The images are obtained S110, wherein the obtained images have a first resolution. The obtained images are subsampled S120 to intermediate images having a second resolution lower than the first resolution and lower than a third resolution. The intermediate images are upsampled S130 to output images having the third resolution, wherein the third resolution is the same for all images of the video stream.

公开(公告)号：US11223834B2

公开(公告)日：2022-01-11

申请号：US17069921

申请日：2020-10-14

Applicant: Axis AB

Inventor： Xing Danielsson Fan ,  Maya Shah ,  Mattias Pettersson ,  Adam Schill Collberg ,  Fredrik Pihl ,  Magnus Söderdahl ,  Peter Wilhelmsson

IPC: H04N7/12 ,  H04N19/176 ,  H04N19/172 ,  H04N19/593 ,  H04N19/61

Abstract: Video encoding, and specifically to a method and an encoder which can adapt the probability of intra refresh of image frame subdivisions based on a count of image frames since a previous refresh and modulated through convex or concave shaped distribution functions are set forth herein.

公开(公告)号：US11750798B2

公开(公告)日：2023-09-05

申请号：US17495839

申请日：2021-10-07

Applicant: Axis AB

Inventor： Fredrik Pihl ,  Mattias Pettersson

IPC: H04N19/105 ,  H04N19/146 ,  H04N19/159 ,  H04N19/176 ,  H04N23/68

CPC classification number: H04N19/105 ,  H04N19/146 ,  H04N19/159 ,  H04N19/176 ,  H04N23/6812

Abstract: The present invention relates to the field of video encoding. In particular, it relates to a method 300 of encoding images captured by a camera and to an image processing device. An image sequence captured with an image sensor of the camera is obtained S310, and an oscillation frequency of a periodic movement of the camera during capturing of the image sequence is determined S320. A base subset of images of the image sequence corresponding to the oscillation frequency is identified S330 and the base subset of images are encoded S340 into an encoded video stream comprising intra frames and inter frames.

公开(公告)号：US11683595B2

公开(公告)日：2023-06-20

申请号：US17370141

申请日：2021-07-08

Applicant: Axis AB

Inventor： Fredrik Pihl ,  Mattias Pettersson

IPC: H04N5/232 ,  H04N7/18 ,  H04N19/167 ,  H04N19/182 ,  H04N19/139 ,  H04N23/80 ,  H04N19/102 ,  H04N19/134 ,  H04N19/61 ,  H04N19/169 ,  H04N19/25 ,  H04N19/48 ,  H04N101/00

CPC classification number: H04N23/80 ,  H04N7/185 ,  H04N19/102 ,  H04N19/134 ,  H04N19/139 ,  H04N19/167 ,  H04N19/182 ,  H04N19/61 ,  H04N19/169 ,  H04N19/25 ,  H04N19/48 ,  H04N2101/00

Abstract: A method and wearable camera for encoding video captured by a wearable camera determines a centre of rotation for an image frame to be encoded. The centre of rotation relates to a rotation of the wearable camera at the time of capturing the video and the image frame comprises multiple groups of pixels. Furthermore, compression levels are set for the multiple groups of pixels of the image frame. The compression levels for the multiple groups of pixels of the image frame are set such that a level of compression increases with a radial distance from the centre of rotation. The image frame is encoded using the compression levels.

公开(公告)号：US11232686B2

公开(公告)日：2022-01-25

申请号：US16729985

申请日：2019-12-30

Applicant: Axis AB

Inventor： Mattias Pettersson

IPC: H04N21/2385 ,  H04N21/2387 ,  G08B13/196 ,  H04N21/2187 ,  H04N21/24 ,  H04N21/2662

Abstract: A method may include transmitting a video stream of a live scene over a network at a real-time transmission speed and detecting an event associated with the video stream being transmitted. The method may include transmitting the video stream over the network at a speed lower than the real-time transmission speed during the event. Transmitting the video stream at the speed lower than the real-time transmission speed may introduce a time stretch for the video stream to be played in slow motion. The method may include reducing a bitrate of the video stream after the event and transmitting the video stream with the reduced bitrate over the network after the event to compensate for the time stretch.