JP-7854791-B2 - Warning generation based on event detection within video footage

JP7854791B2JP 7854791 B2JP7854791 B2JP 7854791B2JP-7854791-B2

Inventors

エドパルム，ヴィクトル
ユアン，ソン
サリーム，アドナン
スフ，ロドリゴ

Assignees

アクシスアーベー

Dates

Publication Date: 20260507
Application Date: 20211014
Priority Date: 20201023

Claims (13)

A method in a camera system (108) for processing a stream of image frames, The process includes generating a hardcoded warning image frame in response to detecting an event, wherein the hardcoded warning image frame is an inter-image frame and includes a motion delta and/or color change with respect to the event image frame , wherein the motion delta includes horizontal and/or vertical movement with respect to the event image frame, and the hardcoded warning image frame is generated by software to produce a desired change in the video stream when displayed to the operator . The method further comprises generating a stream of encoded image frames, wherein the hardcoded warning image frame is inserted into the stream of encoded image frames in display order after the encoded event image frame.
The method according to claim 1, further comprising encoding the event image frame as a hidden image frame.
The method according to claim 1 or 2, wherein the event is an event detected within an event image frame in a stream of image frames or an external event.
The method according to any one of claims 1 to 3 , wherein the motion delta has a configurable size or a predetermined size.
The method according to any one of claims 1 to 4 , wherein the motion delta is applied only to a portion of the warning image frame.
The method according to any one of claims 1 to 5, wherein the color change includes one or more of the following: a more colorful representation compared to the event image frame, a less colorful representation compared to the event image frame, and a representation in which the colors change compared to the event image frame .
The method according to any one of claims 1 to 6 , wherein the color change is applied only to a portion of the warning image frame.
The method according to any one of claims 2 to 7, further comprising removing the hidden state of the event image frame and changing the state of the warning image frame to hidden in order to enable the operator to observe the event captured by the camera system in response to input from the operator .
The method according to any one of claims 1 to 8, wherein the warning image frame is one of a forward prediction frame ( P frame ) including a motion delta with respect to the event image frame, and a bidirectional frame ( B frame ) including a motion delta with respect to the event image frame.
The generation of the hardcoded warning image frame is The method according to any one of claims 1 to 9 , comprising generating the hardcoded warning image frame based on the warning image frame generated outside the camera system (108).
The method according to any one of claims 1 to 10 , wherein the event image frame is a reference frame for the picture group GOP.
A camera system (108), A lens (110) and an image sensor (112) configured to capture a stream of image frames, The system includes an image processing pipeline (302) configured to generate hardcoded warning image frames in response to detecting an event, The hardcoded warning image frame is an inter-image frame and includes a motion delta and/or color change with respect to the event image frame , the motion delta includes horizontal and/or vertical motion with respect to the event image frame, and the hardcoded warning image frame is generated by software to produce a desired change in the video stream when displayed to the operator . The camera system (108) further comprises an encoder (304) configured to generate a stream of encoded image frames , The hardcoded warning image frame is inserted into the stream of encoded image frames in the order of display after the encoded event image frame , camera system (108)
A computer program product for processing a stream of image frames captured by a camera, comprising a computer-readable storage medium implementing program instructions, wherein the computer-readable storage medium is not a transient signal itself, and the program instructions are executable by a processor to carry out the method . The method includes generating a hardcoded warning image frame in response to detecting an event, wherein the hardcoded warning image frame is an inter-image frame and includes a motion delta and/or color change with respect to the event image frame , wherein the motion delta includes horizontal and/or vertical motion with respect to the event image frame, and the hardcoded warning image frame is generated by software to produce a desired change in the video stream when displayed to an operator . The method further comprises generating a stream of encoded image frames, wherein the hardcoded warning image frame is inserted into the stream of encoded image frames in display order after the encoded event image frame, in a computer program product.

Description

This invention relates to a video surveillance system, and more specifically, to generating an alert to an operator in response to detecting an event within video footage. In many surveillance systems, video and other data from numerous cameras and/or other sensors are managed in an operations control room and displayed on monitor screens. Typically, there are several screens in the operations control room, such as 3 to 6 screens. Each screen displays several video sources, for example, 4x4 video sources, which are monitored by the operator. As a result, the operator must simultaneously pay attention to 48 (3x16) to 96 (6x16) video sources in order to detect events within a single video source. Events can include, to name a few, the movement of objects such as vehicles, intruders entering restricted areas, detected faces, and crowded areas. However, due to the large volume of video footage, there is a risk that an event may not be detected in a single video clip, especially if the event is subtle or occurs very quickly while the operator's attention is temporarily diverted from the specific video clip containing the event. Therefore, it is necessary to direct the operator's attention to specific video clips if an event is present within them. The video surveillance system is described in International Publication No. 2006/006081. The video surveillance system consists of smart cameras, a server, and clients connected via an IP network in a wired or wireless configuration. The system has been designed to protect the privacy of the people and goods being monitored. The operation of the smart cameras is optimized to provide a balance between the perceived visual quality of the decoded video and power consumption. The server receives, stores, manages, and transmits video sequences over wired and wireless channels to various clients and users with different device capabilities, channel characteristics, and preferences. The use of seamless and scalable coding of video sequences eliminates the need for transcoding operations at any point in the system. U.S. Patent Application Publication No. 2003/0122667 describes a system and method for enhancing security at self-checkout stations. The system includes a security agent application that runs on terminals at several self-checkout stations. The security agent software generates event messages regarding security events occurring at the station and sends them to a server. The server sends priority event messages as alert messages to a security controller. The security controller is coupled to security cameras, image data storage devices, and image data display devices, and generates control messages for these devices in response to received alert messages. Control messages for security cameras cause the cameras to zoom, focus, tilt, or pan in relation to events occurring at the station. The controller may insert visual alert instructions within the video stream of the monitored camera, or an audible tone within the audio of the video stream, to draw the attention of security personnel to the display of ongoing security events at the station. According to a first aspect, the present invention relates to a method in a camera system for processing a stream of image frames. The method is: - To generate a hardcoded warning image frame in response to detecting an event, wherein the hardcoded warning image frame is an inter-image frame and includes motion delta and/or color changes relative to the event image frame, and the hardcoded warning image frame is generated in software to produce a desired change in the video stream when displayed to the operator, and This involves generating a stream of encoded image frames, in which hardcoded warning image frames are inserted into the stream of encoded image frames in the order they appear, after the encoded event image frames. This method makes it easier for operators to be alerted regarding video material in monitoring situations where suspicious events may occur. The method can be applied to any type of event, rather than being limited by the type of event and/or detection mechanism. The event image frame used herein is an image frame correlated with the event. The event image frame can be an image frame containing the actual event, or an image frame captured at or near the time the event occurred. Furthermore, when used in this disclosure, the represented, hardcoded warning image frame should be understood as a warning image frame generated by software to create a desired change in the video when displayed to the operator. Therefore, it should be understood that the hardcoded warning image frame is not created by the encoder by encoding the image data. Because the warning image frame is hardcoded, it does not need to be encoded by the encoder, but can be directly inserted into the image stream output from the encoder. The desired change in the video when displayed to the operator can be a vibrational motion and/or color change