Abstract: A method of adding comfort noise to a video sequence comprising setting parameters of a deblocking filter of a video encoder to change values during the video sequence, encoding frames of the video sequence using the parameters of the deblocking filter that are set to change values during the video sequence, thereby introducing comfort noise in the video sequence, and including the encoded frames in a bitstream together with an indication of which parameters of the deblocking filter were used when encoding the frames of the video sequence.

Abstract: A power control system for controlling operation of a first battery-powered device positioned at a remote location from a camera. The power control system includes a receiving module, a retrieving module, a comparison module, and a transmission module. The receiving module is configured to receive at least one of a pan angle and a tilt angle of the camera indicative of a field of view. The retrieving module is configured to retrieve a position of the first battery-powered device. The comparison module is configured to compare the pan angle and the tilt angle with the position of the first battery-powered device, and determine whether the first battery-powered device is positioned within the field of view of the camera based on the comparison. The transmission module is configured to transmit instructions to control power consumption of the first battery-powered device, based on the determination.

Abstract: A video encoder receives a frame to be encoded and divides the current frame into blocks of pixels. For each block, a spatial variability is calculated and a cost function used to evaluate a cost for inter-coding the block of pixels is set to be dependent on the spatial variability. A ratio of a weight associated with a cost of encoding a motion vector and a weight associated with a sum of differences value is set to be lower if the spatial variability of the block of pixels in the current frame is below a first threshold compared to if the spatial variability is equal to or above the first threshold. The block is matched with a plurality of blocks in a reference frame, and a cost for inter-coding the block with reference to each of the plurality of blocks in a reference frame is evaluated according to the cost function.

Abstract: The present invention relates to a system and a method for encoding a video stream. The encoding includes determining a level of relevance for areas in an image frame to be included in the video stream, determining a block size value for coding blocks in the image frame, the block size value is depending on the level of relevance determined for the area including each coding block, respectively, encoding the image frame using coding block sizes based on the determined block size values for each of the coding blocks.

Abstract: A method and an image processing entity for applying a convolutional neural network to an image are disclosed. The image processing entity processes the image while using the convolutional kernel to render a feature map, whereby a second feature map size of the feature map is greater than a first feature map size of the feature maps with which the feature kernel was trained. Furthermore, the image processing entity repeatedly applies the feature kernel to the feature map in a stepwise manner, wherein the feature kernel was trained to identify the feature based on the feature maps of the first feature maps, wherein the feature kernel has the first feature map size.

Abstract: A controller and method therein for controlling encoding of a set of images to enable blending of an overlapping area, where a first image and a second image overlap each other are disclosed. The controller encodes macroblocks of the non-overlapping area in the first image using a set of base quantization parameter values, QP-values, and adds the same set of base QP-values to a header of each macroblock. The controller encodes macroblocks of the overlapping area in the first image using a set of first QP values, and adds a modified set of the first QP-values to a header of each macroblock. The controller encodes macroblocks of the overlapping area in the second image using a set of second QP values, and adds a modified set of the second QP-values to a header of each macroblock.

Abstract: The present invention relates to monitoring applications. In particular, the present invention relates to a method, device and system for detecting a loitering event in which the loitering time of objects with different object IDs, which subsequent to each other spends time within an area of interest within a monitored scene, will be combined.

Abstract: Autofocusing a camera while zooming may include zooming the lens to a first zoom position, measuring a first object distance from the camera to an object on which to focus, determining a first focus start position using the first object distance, performing a first autofocus using the first focus start position as a starting point, thereby determining a first focus position. A first lookup object distance may be determined based on the first determined focus position. A first correction factor may be calculated as a ratio between the first lookup object distance and the first object distance. The lens may be zoomed to a second zoom position, and a second focus position may be determined using a second object distance based on the first object distance and a second correction factor based on depths of field at the second and first zoom positions.

Abstract: Apparatus, systems and techniques associated with battery powered wireless camera systems. One aspect of the subject matter described in this specification can be embodied in a system that includes a battery powered wireless camera including an internal battery to provide energy and a burst transmission unit to transmit information during burst periods. The system includes a base station, separated from the battery powered wireless camera, in wireless communication with the battery powered wireless camera to receive information from the battery powered wireless camera. The base station is configured to process the received information and includes a web server to transmit the processed information to a client. Other embodiments of this aspect include corresponding systems, apparatus, and computer program products.

Abstract: A monitoring camera is equipped with a touch sensor in a camera cover glass, which senses positions of objects touching or being close to the cover glass. The touch sensor aids the camera in separating image data depicting objects on the cover glass from image data depicting the monitored scene. This information may be used when choosing image capture settings, by indicating to the camera which image regions are less important to take into account, and to avoid false alarms which otherwise may occur when rain drops or insects on the cover glass are mistaken for events in the scene.

Abstract: Described is a method and apparatus for controlling a degree of compression of a digital image, and more specifically to such method and apparatus which receives a stereoscopic digital image, and controls a degree of compression of the digital image based on block matching characteristics between the two images of the stereoscopic digital image.

Abstract: A lens arrangement for a monitoring camera and a monitoring camera including a lens arrangement is provided. The lens arrangement includes a lens member having a connection portion with an outer thread, an adjustment member having a through hole for receiving the connection portion and an inner thread corresponding to the outer thread, a holder member having a receiving portion for receiving the connection portion and an inner thread corresponding to the outer thread. The lens arrangement is assembled by the connection portion being screwed into the through hole and further into the receiving portion. The receiving portion has a top engagement surface and the adjustment member has a bottom engagement surface. The adjustment member is movable relative to the holder member by screwing between non-engaging and engaging states. In the engaging state, the bottom engagement surface wedgingly engages with the top engagement surface for locking the lens member.

Abstract: There is provided a method and system for tracking a plurality of objects in a sequence of images. The method comprises: receiving an image from a sequence of images; calculating, based on the received image, a detection probability map which, for each state of a predefined set of states of an object, specifies a probability that any of the plurality of objects is detected in that state in the received image; updating, based on the calculated detection probability map, an object identity map and an accumulated probability map recursively from a previous object identity map and a previous accumulated probability map corresponding to a previously received image of the sequence of images, and tracking each object in the received image based on the updated object identity map and the updated accumulated probability map.

Abstract: The disclosure relates to a method, apparatus and system for detecting and reducing the effects of color fringing in digital video acquired by a camera comprising an iris. The method comprises: acquiring, by the camera, a first digital image frame using a first camera setting, including a first iris aperture size; acquiring, by the camera, a second digital image frame using a second camera setting, including a second iris aperture size, wherein the second aperture size is smaller than the first aperture size; comparing the first and the second digital image frame, at least a specific color component thereof; localizing regions having a disproportional intensity ratio in the specific color component between the first digital image frame and the second digital image frame; and reducing the specific color component in the localized regions for subsequently acquired digital image frames.

Abstract: A camera arrangement comprising a camera base for mounting the camera arrangement to a surface. The camera base comprises a central receiving portion. The camera arrangement further comprises a dome comprising a central section with a through-going opening; and an attachment device configured to attach the dome to the central receiving portion. The attachment device comprises an attachment portion configured to extend through the through-going opening of the dome and to lockingly engage a complementary attachment portion of the central receiving portion, and an abutment portion configured to abut an outside surface of the dome.

Abstract: A method and crystal oscillator circuit for matching a supply voltage with a drive level of a crystal are disclosed. The crystal oscillator circuit is based on a Pierce oscillator circuit which further comprises a capacitor Cd. The capacitor Cd together with the load capacitor act as a capacitive voltage divider and the capacitance of this capacitor may be selected to reduce the supply voltage to match the drive level of the crystal oscillator without affecting the oscillation margin of the crystal.