Abstract: A device and method merge a first candidate area relating to a candidate feature in a first image and a second candidate area relating to a candidate feature in a second image. The first and second images have an overlapping region, and at least a portion of the first and second candidate areas are located in the overlapping region. An image overlap size is determined indicating a size of the overlapping region of the first and second images, and a candidate area overlap ratio is determined indicating a ratio of overlap between the first and second candidate areas. A merging threshold is then determined based on the image overlap size, and, on condition that the candidate area overlap ratio is larger than the merging threshold, the first candidate area and the second candidate area are merged, thereby forming a merged candidate area.

Abstract: There is provided a method for capturing a sequence of image frames in a thermal camera having a microbolometer detector comprising: capturing a first sequence and a second sequence of image frames with a shutter of the thermal camera being in a closed state and an open state, respectively. While capturing each of the first and the second sequence, an integration time of the microbolometer detector is switched between a plurality of integration times according to one or more repetitions of a temporal pattern of integration times. The method further comprises correcting image frames in the second sequence that are captured when the integration time is switched to a particular position within the temporal pattern of integration times using image frames in the first sequence that are captured when the integration time is switched to the same particular position within the temporal pattern of integration times.

Abstract: A method for determining whether or not a transparent protective cover of a video camera comprising a lens-based optical imaging system is partly covered by a foreign object is disclosed. The method comprises: obtaining (402) a first captured image frame captured by the video camera with a first depth of field; obtaining (404) a second captured image frame captured by the video camera with a second depth of field which differs from the first depth of field; and determining (406) whether or not the protective cover is partly covered by the foreign object by analysing whether or not the first and second captured image frames are affected by presence of the foreign object on the protective cover such that the difference between the first depth of field and the second depth of field results in a difference in a luminance pattern of corresponding pixels of a first image frame and a second image frame.

Abstract: A camera for introducing light pulses in an image stream, comprising an image sensor arranged to capture an image stream, the image sensor comprising a plurality of pixels arranged to capture light of a first wavelength range. The at least one of the plurality of pixels is covered by a first material which is arranged to transform light of a second wavelength range to light of the first wavelength range. Further the camera comprises a first light source arranged to emit light pulses of light of the second wavelength range onto the first material, thereby causing the image sensor to register light pulses in the at least one pixel covered by the first material.

Abstract: An image processing device, a camera and a method of encoding a sequence of video images into a single video stream with dynamic bitrate are provided. The sequence of video images is encoded into frames of a base layer of the single video stream using a base layer resolution and a base layer compression level. Video images of the sequence of video images corresponding to respective times before detecting an event trigger are encoded into a first set of frames of an extended layer of the single video stream. The event trigger is detected and upon detecting the event trigger, video images of the sequence of video images corresponding to respective times after detecting the event trigger are encoded into a second set of frames of the extended layer using a higher resolution than the base layer resolution or a lower compression level than the base layer compression level.

Abstract: An exposure time controller for controlling an exposure time (ET) variable of a video camera, which is associated with an auto-exposure algorithm configured to reduce an exposure mismatch (?E) by incrementing and decrementing the ET variable, which comprises: a memory for recording ET values applied while the video camera is imaging a scene and the algorithm is active; and processing circuitry configured to: determine that the exposure mismatch exceeds a threshold while the video camera is imaging the scene; estimate a distribution of the recorded ET values; based on the estimated distribution, identify multiple relatively most frequent ET values; and, in reaction to determining that the exposure mismatch exceeds the threshold, assign one of the identified ET values to the ET variable.

Abstract: A threaded joint arrangement with visual and tactile indication of correct tightening force, includes a threaded fastener having a fastener shaft and a fastener head, a biasing member, a first object provided with a cavity in a reference surface with a bottom surface provided with a through hole, and a second object with a threaded hole. The through hole is aligned with the threaded hole and the fastener shaft extends through the through hole and is in threaded engagement with the threaded hole. The biasing member is arranged in the cavity between the fastener head and the bottom surface and is compressed between the fastener head and the bottom surface in response to rotation of the threaded fastener. An alignment surface is movable by rotation of the threaded fastener between a first position outside the cavity, a second position flush with the reference surface and a third position inside cavity.

Abstract: There is provided a computer implemented method for displaying a video stream of a scene (100) captured by a video capture device on a display of a client device.

Abstract: A method for determining images plausible to have a false negative object detection comprises providing a group of historic trajectories, wherein each historic trajectory comprises a reference track that represents one or more historic tracks and comprises an object class of historic object detections that belong to the one or more historic tracks; performing tracking; performing object detection; for a determined track that does not match any determined object detection, comparing the determined track with reference tracks of historic trajectories for identifying a matching reference track; upon identifying a matching reference track, defining images of the determined track as being plausible to have a false negative object detection for the object class of the historic trajectory comprising the matching reference track; and upon not identifying a matching reference track, defining the determined track as a false positive track.

Abstract: A video encoding method comprises encoding a series of images of original video data into an encoded video stream comprising key frames and delta frames, wherein the delta frames are organized in a hierarchical prediction pattern comprising a plurality of temporal layers. The video encoding method further comprises adding to the encoded video stream a hidden delta frame for at least some of the key frames. Each hidden delta frame corresponds to a key frame, is based on same original video data as the corresponding key frame and is referring to a previous key frame in the encoded video stream. Also, a method of reducing a file size of the video stream encoded according to the video encoding method is disclosed.

Abstract: A method for enhancing the performance of a video camera capable of switching between night-mode and day-mode operation comprises: acquiring a first sequence of images with the video camera with an IR-transmission filter of known transmission characteristics in front of an image sensor of the video camera, the IR transmission filter having a transmission in the IR-region of above 30%, and acquiring a second sequence of images with the video camera without the IR-transmission filter. The method then uses the first and second image sequences to measure the contribution from visual light, or a contribution of IR radiation to images in the first or second stream of images. The measurements utilize an assessment of the calculated contribution to improve the performance of the video camera by switching the video camera from night-mode to day-mode, or add color information to images acquired with IR-radiation to the image sensor.

Abstract: A camera having a heating arrangement comprising a heater arranged to supply heat to a window. A thermally conductive member is arranged in contact with a housing and with the heating arrangement, when a temperature at the conductive member is below a threshold, to transfer heat supplied by the heater to the housing. A thermally insulating member is arranged in proximity with the housing and the heating arrangement. The conductive and/or insulating member is configured to, when the temperature increases above the threshold during heater operation, change its extension to enable contact between the insulating member and the housing and between the insulating member and the heating arrangement, and to disable contact between the conductive member and the housing and between the conductive member and the heating arrangement, thereby thermally insulate the housing from the heater.

Abstract: A video capturing device configured to capture video data, the image capturing device comprising: an image processing pipeline configured to generate a video stream from the captured video data; an encryption key activating module configured to, upon request, activate an encryption key and deactivate any previously activated encryption key used for encrypting the video stream, such that only one encryption key is activated to be used for encryption of the video stream at each instance in time; an encryption scheduler module configured to, at a predetermined time interval, instruct the encryption key activating module to activate an encryption key; an event handling module configured to, as a response to receiving indications of a detected event, instruct the encryption key activating module to activate an encryption key; an encryption module configured to encrypt the video stream using the one activated encryption key.

Abstract: Apparatus are provided for generating an object classification for an object, the apparatus comprising an image sensor, a radar sensor, and a processing unit, the processing unit configured to perform the steps of: receiving image data for the object from the image sensor, operating an image-based object classifier on the image data to generate an image-based object classification, receiving radar data for the object from the radar sensor, operating a radar-based object classifier on the radar data to generate a radar-based object classification, selecting between the image-based object classification and the radar-based object classification to output as the object classification for the object, determining if a training condition is met by the radar-based object classification, and training the radar-based object classifier using the image-based object classification when the training condition is met by the radar-based object classification.

Abstract: Methods and apparatus, including computer program products, for detecting malfunction in a thermal camera. A first average response value is determined for a first shutter image captured by an image sensor in the thermal camera. A second average response value is determined of a second shutter image captured by the image sensor in the thermal camera. The first average response value and the second average response value are compared. In response to determining that the first average response value and the second average response value differ by more than a predetermined value, an indication of a malfunction of the thermal camera is provided.

Abstract: Methods and apparatus, including computer program products, for controlling a speaker, which is electrically powered with a low-power source and connected to a short-term energy storage. Audio is received for playback on the speaker. A time-resolved power analysis of the audio is acquired and a time-resolved speaker power requirement required by a speaker playing back the audio is calculated. The time-resolved speaker power requirement is compared with a combined capacity of the low-power source and the short-term energy storage. One or more of: a dynamic range, a frequency range, and an output gain of a digital signal processor are adjusted such that the speaker power requirement meets the combined capacity of the low-power source and the short-term energy storage for the duration of a playback of the received audio on the speaker.

Abstract: A controller for reading both an RS485 data signal and a Wiegand data signal from a user connector having two output ports. The controller comprises an RS485 transceiver with two input ports, each of which is connected to a respective one of the two output ports of the user connector or reading one data signal on each of the output ports from the user connector, and an output port for providing an RS485 data signal that is defined by the data signals read on the two output ports. The controller comprises an RS485 interface for receiving the RS485 data signal, and a Wiegand interface for receiving the RS485 data signal and a data ready port connected to the two input ports via a first logic circuit for determining whether the RS485 data signal is to be read as a Wiegand data signal or not on the Wiegand data port.

Abstract: A method for producing an interference reduced radar image comprises receiving a measured sequence of beat signals; identifying one or more interference segments within the measured sequence of beat signals, an interference segment being a segment subject to an interference; doctoring the measured sequence of beat signals by creating a doctored representation of the measured sequence of beat signals in the form of a matrix Y; creating a doctoring mask representing the doctoring of the measured sequence of beat signals, the doctoring mask being a matrix M; and estimating a reconstructed range-doppler image {circumflex over (X)} from Y and M, wherein the reconstructed range-doppler image is a range-doppler image of Y which is deconvolved using M; such that doctoring the measured sequence of beat signals at least partially removes interference effects and estimating a reconstructed range-doppler image at least partially removes image artefacts created by the doctoring.