US 12,120,421 B2
Event video sequences
Axel Keskikangas, Lund (SE); Viktor Edpalm, Lund (SE); and Mattias Pettersson, Lund (SE)
Assigned to AXIS AB, Lund (SE)
Filed by Axis AB, Lund (SE)
Filed on Jan. 7, 2022, as Appl. No. 17/570,774.
Claims priority of application No. 21160211 (EP), filed on Mar. 2, 2021.
Prior Publication US 2022/0286621 A1, Sep. 8, 2022
Int. Cl. H04N 23/65 (2023.01); G06T 5/00 (2006.01); G06V 20/40 (2022.01); G11B 20/10 (2006.01); G11B 27/028 (2006.01)
CPC H04N 23/651 (2023.01) [G06T 5/00 (2013.01); G06V 20/44 (2022.01); G11B 20/10527 (2013.01); G11B 27/028 (2013.01); G11B 2020/10712 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of recording an event video sequence, wherein the event video sequence comprises a pre-event video sequence showing a monitored scene during a pre-determined length of time before an event detection, and a post-event video sequence showing the monitored scene from the time of the event detection:
the method comprising the steps of:
continuously capturing image frames,
continuously storing, in a pre-event buffer, newly captured image frames by adding them to a set of pre-event image frames corresponding to the pre-determined length of time, wherein the newly captured image frames that are stored in the pre-event buffer have not yet been subject to image processing consisting of one or more of defect pixel correction, white balancing, de-mosaicing, matrixing, gamma correction, sharpening, noise filtering, scaling and encoding in an image processing unit,
receiving a first signal indicating that an event is detected,
upon receiving the first signal,
discontinuing the storing of newly captured image frames in the pre-event buffer,
feeding newly captured image frames to the image processing unit,
performing image processing of the newly captured image frames in the image processing unit, and
storing the processed image frames as the post-event video sequence in a memory,
receiving a second signal indicating that the event has ended,
upon receiving the second signal,
discontinuing feeding newly captured image frames to the image processing unit,
feeding the set of image frames from the pre-event buffer to the image processing unit,
performing image processing of the set of image frames in the image processing unit, and
storing the processed set of image frames as the pre-event video sequence in the memory;
wherein the image processing includes one or more of the following: defect pixel correction, white balancing, de-mosaicing, matrixing, gamma correction, sharpening, noise filtering, scaling and encoding.