65 results about "Luminance meter" patented technology

The invention relates to the technical field of intelligent control, and discloses an ultra-low power consumption miniature LED visible light intensity self-adaptive regulation and control method and system, and the method comprises the steps: obtaining an analog light intensity signal, and carrying out the smoothing processing of the analog light intensity signal, and obtaining an environment light intensity value; calculating a light intensity change rate, and if the light intensity change rate exceeds a dynamic threshold value, marking an environment state and outputting a light intensity difference value; generating a preliminary adjustment instruction according to the state matching control parameter and the difference value quantization mapping, and calculating target light intensity in combination with the basic brightness; after executing the instruction, calculating actual and target deviation, and iteratively correcting to obtain a light intensity control signal; if the power consumption exceeds the limit, optimizing the signal amplitude; the input driving circuit analyzes the synthesized pulse current, excites pixels to emit light and gathers to obtain adjustment data; and if the visual contrast is lower than a threshold value, the change rate is adjusted again to realize closed-loop refining, and the light intensity adjustment accuracy is improved. The method can improve the real-time sensing capability of ambient light.

The invention relates to the technical field of automobile testing, and discloses a method and system for evaluating and testing visual field glare of a driver in a cabin, and the method comprises the following steps: starting from the position of the eyes of the driver, capturing a brightness distribution image of the whole visual field, and dividing the image into a plurality of sub light source regions around a glare source; dividing the visual field into a main sight area and a residual light sight area according to the attention distribution of the driver, and endowing sub light source areas falling into different areas with different weight values; calculating a unified glare index according to the weighted sum of the glare intensity of each sub light source area and the background brightness in the cabin; and finally, comparing the index with a preset threshold value, and outputting an evaluation result. According to the method, the large-area light source is divided into the sub-light sources, weighted calculation is carried out in combination with the attention of the driver, the problem that a traditional glare evaluation model is not suitable for a close-range non-point light source scene of the automobile cabin is solved, a scientific evaluation system matched with the automobile cabin is established, and the glare evaluation result is more accurate.

A video recording control device includes an imaging data obtaining unit that obtains imaging data; a luminance calculating unit that divides the imaging data into regions and calculates luminance for each divided region; a light source region setting unit that sets, as light source regions, the regions for which the luminance calculated by the luminance calculating unit is equal to or higher than a luminance threshold value; a luminance adjusting unit that adjusts the luminance of the light source regions either to the average value of luminance of other regions excluding the light source regions or to a predetermined value, and obtains post-adjustment data; and a recording control unit that records, in a recording unit, the imaging data along with the post-adjustment data having the luminance adjusted by the luminance adjusting unit.

The application relates to a face brightness calculation method, device, medium and equipment, the method comprises the following steps: acquiring a first region of interest in an image, the first region of interest comprising a face; determining a target brightness difference value between a central region and an edge region of the first region of interest; adjusting the size of the first region of interest according to the target brightness difference value to obtain a second region of interest; and determining the brightness of the second region of interest as the face brightness of the image. The brightness difference value between the edge region and the central region of the region of interest is calculated, the size of the region of interest is adjusted through the brightness difference value, the size of the face region is converged to an ideal size, the face brightness is calculated, the accuracy of face brightness statistics is improved, different shooting scenes are adapted to, and a good portrait shooting effect is realized.

The utility model discloses an LED lamp detection device which comprises a detection table, the top of the detection table is fixedly connected with a detection box, the top of the detection box is covered with a fixing cover, the top of the fixing cover is connected with a brightness meter in a penetrating mode, the bottom of the fixing cover is fixedly connected with a hanging bracket, the hanging bracket is fixedly connected with an LED installation base, and the LED installation base is fixedly connected with a light source. The beneficial effects of the utility model are that the LED lamp to be detected is firstly installed on the LED installation seat, then the lifting mechanism drives the fixed cover to close the detection box, the LED lamp on the LED installation seat extends into the detection box to carry out darkroom detection, then the LED installation seat is controlled to be electrified, and the LED lamp can be conveniently and rapidly detected. During illumination, the brightness meter can detect the brightness, the heat dissipation mechanism can dissipate heat generated by the LED lamp in the detection process, the structure is reasonable, the brightness of the darkroom can be conveniently detected, and operation is convenient.

The application provides an image brightness adjusting method, a light adjusting device and an endoscope. The image brightness adjusting method is applied to the light adjusting device of the endoscope. The light adjusting device comprises a CMOS exposure time adjusting interval, a light source brightness adjusting interval and a CMOS gain adjusting interval. The image brightness adjusting method comprises the following steps: acquiring the average brightness of a current frame image and a preset target brightness; judging the current adjusting interval; calculating the adjusting proportion coefficient of the current adjusting interval according to the average brightness of the current frame image and the target brightness; and adjusting the image brightness in the current adjusting interval according to the adjusting proportion coefficient. Compared with the prior art, the application realizes dynamic adjustment of the image brightness by setting the adjusting proportion coefficient, widens the adjusting range, and improves the image quality as much as possible under the premise of achieving the same target brightness.

The invention provides a novel target and background contrast ratio measuring method, and belongs to the field of precise instrument manufacturing. When an image gray value is used for measuring the contrast ratio of a target and a background, imaging parameters of a detector and parameters of an optical system need to be calibrated, so that brightness information of the target and the background is truly reflected. The method comprises the following steps: respectively carrying out contrast measurement calibration on standard target plates with different contrast values under different illuminations by using a brightness meter, measuring the contrast values of the standard target plates by using an image gray value, fitting the contrast measured by the image gray value with the contrast measured by the brightness value in software by using a mathematical fitting algorithm, and calculating the contrast value of the standard target plates. The purpose of measuring the target background contrast value by using the image gray value is achieved. And establishing relational mapping between brightness and a gray value, defining a rule of a sampling sample, selecting a target and a background, and finally calculating a contrast ratio between the target and the background.

The utility model discloses a spectrum correction type imaging chrominance meter, which is used for improving the test precision and shortening the test time. The color and brightness meter comprises a lens, a color and brightness meter main body and a shaping lens group, the lens is connected to the color and brightness meter main body, and the lens is used for transmitting a light beam into the color and brightness meter main body; a wheel rotating disc and a built-in spectrograph are arranged in the chrominance meter main body, an optical fiber is arranged on the chrominance meter main body, the optical fiber is connected with the built-in spectrograph, a reflecting prism is arranged on the wheel rotating disc, and the wheel rotating disc is controlled to rotate so that the reflecting prism can be arranged at the position corresponding to the lens. The reflecting prism is used for reflecting the light beam; the shaping lens group is arranged on a light path of the light beam path and used for converging the light beams into parallel light beams, and the parallel light beams irradiate the end face of the optical fiber.

The present disclosure relates to a technology for measuring luminance to control tunnel lighting, wherein an area ratio of luminance-calculated areas included in a tunnel entrance image is corrected on the basis of an installation position of an optical device, and a reference position luminance value for controlling tunnel lighting is calculated by reflecting a correction coefficient set on the basis of the installation position, surrounding environmental factors, and the like, in luminance measurement values of the corrected luminance-calculated areas.

The utility model relates to the technical field of spectral radiometric calibration, and discloses a high-precision spectral radiometric calibration device. Comprising a machine shell and a base, the base is fixedly connected to the bottom of the machine shell, a conical reflecting cover is fixedly connected to the inner wall of the left side of the machine shell, a pipe body and a protective reflecting cylinder are fixedly connected to the side wall of the conical reflecting cover, the protective reflecting cylinder is arranged on the inner wall of the pipe body, and a plurality of optical fibers are arranged on the inner wall of the protective reflecting cylinder in a surrounding mode. The plurality of optical fibers are in close contact, and a gap is arranged between the tube body and the protective reflective cylinder. The light-emitting surface of the light source is attached to the inner wall of the conical reflecting cover, then the threaded rotating rod is rotated to rotate along the inner wall of the threaded ring so that the clamping plates can be pushed to be clamped on the side wall of the light source, the light source can be kept stable, follow-up calibration treatment is facilitated, the light source irradiates light beams to the ends of the optical fibers, and therefore the light source is more stable. The optical fiber can completely refract the light beam to the spectral radiance meter, and calibration processing can be carried out.

Embodiments of the present application disclose a method and device for calculating image brightness, electronic equipment and storage medium. The method comprises: performing face detection on a target image to determine a face rectangular region in the target image; determining a face region in the face rectangular region; calculating a proportion of the face region in the face rectangular region; determining an exposure weight table corresponding to the face rectangular region according to the proportion; and calculating the brightness of the face rectangular region based on the exposure weight table. The embodiments can improve the accuracy of image brightness calculation.

This application provides a method and system for measuring the performance of a light source, which improves the convenience of measuring optical performance. The method includes: acquiring a first image; the first image is an image of the brightness detection area when a first attenuator and a first filter are placed directly in front of the lens; performing brightness analysis based on the first image to obtain a brightness calculation result; acquiring a second image, a third image, and a fourth image; the second image is an image of the chromaticity detection area when the first filter and the second attenuator are placed directly in front of the lens; the third image is an image of the chromaticity detection area when the second filter and the second attenuator are placed directly in front of the lens; the fourth image is an image of the chromaticity detection area when the third filter and the second attenuator are placed directly in front of the lens; performing chromaticity analysis based on the second image, the third image, and the fourth image to obtain a chromaticity calculation result; and combining the brightness calculation result and the chromaticity calculation result to obtain a light source performance measurement result.

The invention relates to the field of video analysis, in particular to an intelligent video analysis method and system adaptive to environment change, and the method comprises the steps: obtaining a current frame image, and calculating a brightness mean value of the current frame image; calculating an illumination abrupt change factor based on the brightness; extracting feature point motion vectors between the current frame image and the previous frame image based on a Lucas-Kanade optical flow method to obtain a motion vector sequence; the average amplitude of high-frequency components with the frequency larger than a set threshold value in the motion vector sequence is obtained; obtaining a high-frequency vibration entropy based on the information entropy of the modulus length in the motion vector sequence and the average amplitude of the high-frequency component; combining the illumination abrupt change factor and the high-frequency vibration entropy to obtain a comprehensive environment complexity index; performing enhancement processing on the current frame image to obtain an enhanced image; inputting the enhanced image into a target detection model for detection; and giving out an early warning prompt in response to the existence of the detection target. The accuracy of the detection result is improved.

The present application relates to a kind of high dynamic range image fusion method and device of ToF system.The present application judges whether the four phase data of high gain / long exposure time image are all luminance non-saturation first, if all are luminance non-saturation, then high gain / long exposure time image is used to carry out luminance calculation, otherwise low gain / short exposure time image is used to carry out luminance calculation, can only need to calculate the image of ToF system infrared thermal imager, need not simultaneously calculate two images, save the ToF system MCU operation time, can quickly carry out high dynamic range image fusion, can increase the dynamic range of ToF system infrared thermal imager image, avoid the phenomenon that only use low gain / short exposure time image causes the noise of image to be large, improve the image quality of ToF system infrared thermal imager.

The invention relates to the technical field of absolute response calculation of in-orbit optical remote sensing satellites, in particular to an in-orbit satellite response calculation method based on a point light source, which comprises the following steps of: calculating entrance pupil radiance and a response value of a remote sensing camera; calculating a spectral response function and a spectral response bandwidth of the remote sensing camera; equivalent entrance pupil radiance is calculated through wavelength infinitesimal elements; performing least square fitting calculation through the equivalent entrance pupil radiation brightness and the response value to obtain an absolute radiation calibration coefficient; calculating the absolute radiation brightness under the equivalent extended light source; the atmospheric upper bound absolute radiation brightness is calculated through the atmospheric transmittance and the absolute radiation brightness under the equivalent extended light source, and the equivalent radiation brightness is calculated through the spectral response bandwidth; and the output response value of the remote sensing camera is calculated according to the equivalent spectral radiation brightness. According to the method, on-orbit satellite response calculation based on the point light source is realized by utilizing a point source target radiation transmission principle and combining a basic principle of optical remote sensing camera radiation calibration.

The invention belongs to the field of infrared thermal imaging temperature correction, and particularly relates to a curved surface infrared thermal imaging detection temperature correction device and method based on a laser array. The correction method comprises the steps of establishing a correction device system, measuring a laser array, calculating an included angle between a normal direction of each measurement point and a radiation source direction, calculating a correction factor, measuring radiation brightness by a radiation emission method, calculating an uncorrected emissivity and a real emissivity, and calculating a real temperature. According to the correction device and method, a set of efficient, accurate and high-adaptability curved surface object temperature measurement system is formed by integrating a laser array scanning technology, radiation reflection method measurement and a computer processing technology, and efficient, accurate and high-adaptability detection of the surface temperature of the curved surface object is achieved; a traditional complex algorithm and a large amount of calculation processes are simplified, the influence of the curved surface shape on temperature measurement is effectively solved through the dynamic correction factor, and the measurement precision and reliability are remarkably improved.

Aspects of the present invention relate to a phototherapy system, comprising at least one radiative source configured to produce electromagnetic radiation (EMR) in one or more spectral bands, one or more sensors, and a controller that performs operations comprising calculating a point of gaze, calculating a distance between the subject and the at least one radiative source, setting a brightness to a brightness threshold when the calculated gaze of the subject is directed toward the at least one radiative source and the calculated distance is within an operational range, calculating an exposure time of the subject based on the calculated point of gaze and the brightness, and setting the brightness to a second brightness threshold when the exposure time exceeds a treatment duration, wherein the brightness of the at least one radiative source has a radiated power above a power threshold within a circadian wavelength range.

The embodiment of the invention provides an image quality guarantee method, a controller, a system and a storage medium, and relates to the technical field of image processing. The method comprises the following steps: determining an illumination area of the phase control lamp; wherein the illumination area comprises at least two illumination sub-areas; shooting the illumination area to obtain an initial image, and obtaining the pixel brightness of the initial image; performing target detection on the initial image to obtain target information of at least two targets; wherein the target information comprises a coordinate range and a target type; performing brightness calculation according to the coordinate range of each target and the pixel brightness of the initial image to obtain weighted brightness of each target; and if the brightness of the illumination sub-area where the target is located is different from the weighted brightness of the target, adjusting the brightness of the illumination sub-area through the phase control lamp. The embodiment of the invention can improve the image shooting quality.

Target images include a saturated image group where luminance of a predetermined local region is saturated, a first image group captured on one side in an optical axial direction, which is viewed from image capture positions of the saturated image group and toward which a displacement distance from an in-focus position increases. An in-focus degree acquisition method includes calculating, for each target image, a local in-focus degree indicating the degree of focusing on a local region in accordance with the luminance of the local image; correcting and lowering the local in-focus degree of the local region for the saturated image group; and correcting and lowering the local in-focus degree of the local region for one first image captured at an image capture position closest to the image capture positions of the saturated image group among the first image group.

This invention provides an imaging device, an exposure control method, and a program that enable natural exposure tracking during manual focus (MF) operation in full-time MF mode. [Solution] When full-time MF mode is set on camera 1 and images are being captured periodically, if the focus ring is not being operated by the user, the exposure at the time of shooting is adjusted using a second metering value calculated based on the brightness of a second region corresponding to the focal position at the time of image capture, which is narrower than the first region, and the first metering value. If the focus ring is being operated by the user, the exposure at the time of shooting is adjusted using a first metering value calculated based on the brightness of the first region of the captured image, without calculating a second metering value.

The invention relates to a road information board working performance detection device based on an unmanned aerial vehicle. The road information board working performance detection device is composed of the unmanned aerial vehicle, a high-definition camera, a color brightness meter, an infrared scanner and data processing software. Wherein the color brightness meter and the infrared scanner are used for detecting the performance of the highway information board, and the high-definition camera is mainly used for checking fault modules of the information board and rechecking the functions of the information board. The detection device is generally arranged at the top end of a detection vehicle, performs power supply and information uploading when the vehicle stops, can operate singly after arriving near a highway information board, can also perform real-time linkage work through a preset program, realizes one-stop data acquisition of functions, performance and operation states of the information board, can perform detailed technical condition evaluation on the operation information board, and has a wide application prospect. And data support is provided for later scientific maintenance.

An apparatus for measuring glare in ETC gantry lighting, which apparatus belongs to the field of highway ambient lighting detection. The apparatus comprises a locator (1), a reflected signal demodulator (3-1), a reflected signal sensor (3-2), a transmitted signal modulator (4-1), a signal transmitter (4-2), a transmitted signal demodulator (5-1), a transmitted signal sensor (5-2), a transmissive-reflective mirror set (6), detectors (7, 8), an upper vertical illuminance detector (9), cameras (10, 11, 12), and a switcher (14). Further provided is a method for measuring glare in ETC gantry lighting. The reflectance and luminance of the ground below an ETC gantry are measured to obtain a ground luminance calculation formula, so as to realize the acquisition of ground luminance at a short distance, thereby solving the problems of there being relatively excessive external stray light interference caused by the use of a luminance meter, etc. for long-distance luminance measurement, and the measurement accuracy of the luminance meter decreasing when the distance is relatively long; moreover, by means of supplementary light luminance at different orders of magnitude which are acquired by means of switcher blades having different light transmittances, integrating with the sensitivity advantages of left and right cameras in a high luminance region and a low luminance region, a system error is reduced, thereby obtaining an accurate comprehensive illuminance value.

The application provides a backlight uniformization control method and device, equipment and medium of a liquid crystal display, and belongs to the technical field of liquid crystal display, and the method comprises the following steps: dividing a screen of the liquid crystal display into multiple display areas based on screen luminance attenuation coefficients and backlight source position data of the liquid crystal display; calculating picture luminance variation and picture luminance variation rate of each display area based on average pixel luminance data of the display area; determining the picture working condition of the display area based on the luminance variation and the picture luminance variation rate of each display area; calculating compensation luminance parameters of the display area based on the picture working condition, the inherent backlight attenuation coefficient and the preset target luminance of each display area; and determining target output luminance of a backlight light control unit based on initial output luminance and the compensation luminance parameters of the backlight light control unit corresponding to each display area. The application can solve the problem of non-uniform backlight display in the uniform dimming mode.

A display driving method according to an embodiment may comprise the steps of: measuring brightness of a panel; calculating a lookup table (LUT) based on the measured brightness; and calculating a low gray value and a high gray value for the target brightness based on the LUT. A display driving apparatus according to an embodiment may include: a measuring unit for measuring brightness of a panel; a first calculation unit for calculating a lookup table (LUT) based on the measured brightness; and a second calculation unit for calculating a low gradation value and a high gradation value for the target luminance based on the LUT.

The invention provides a multispectral imaging sensor radiation calibration method comprising the following steps: S1, using a multispectral imaging sensor to collect an image, the image comprising a diffuse reflection calibration plate, and calculating to obtain the radiance reflected by the diffuse reflection calibration plate; s2, photographing a target ground object by using a multispectral imaging sensor, and calculating to obtain radiance reflected by the diffuse reflection calibration plate; and calculating the surface reflectance of the normalized diffuse reflection calibration plate based on the radiance reflected by the diffuse reflection calibration plate obtained in the step S1 and the radiance reflected by the diffuse reflection calibration plate obtained in the step S2. According to the method, radiation calibration can be carried out on the multispectral imaging sensor carried on the unmanned aerial vehicle or the ground mobile platform under any weather conditions. The invention also correspondingly provides a radiation calibration system for the multispectral imaging sensor.

The invention discloses a background light luminance meter system, and relates to the technical field of photometers. The system comprises an optical acquisition module used for receiving background light from a target area; the photoelectric conversion module is in light path connection with the optical acquisition module and is used for converting the background light into an electric signal; the signal conditioning module is connected with the photoelectric conversion module and is used for processing the electric signal so as to expand the measurement dynamic range; and the data processing module is connected with the signal conditioning module and is used for executing nonlinear correction, temperature compensation and spectrum matching compensation on the processed electric signal so as to output a corrected brightness value. According to the invention, high-precision brightness measurement in a wide dynamic range can be realized, and a measurement result is highly matched with visual perception of human eyes through multi-dimensional compensation.

The application relates to the technical field of intelligent control, and discloses a kind of ultra-low power consumption micro-LED visible light intensity self-adaptive regulation and control method and system, the method includes obtaining analog light intensity signal and obtaining ambient light intensity value by smoothing processing;Calculate the light intensity change rate, if it exceeds dynamic threshold, mark the environment state and output the light intensity difference value;According to state matching control parameter, with difference value quantization mapping generates preliminary adjustment instruction, combines basic brightness to calculate target light intensity;Calculate the actual and target deviation after executing the instruction, and obtain the light intensity control signal by iterative correction;If power consumption is over limit, then optimize signal amplitude;Input drive circuit analyzes and synthesizes pulse current, excites pixel to emit light and converges to obtain adjustment data;Calculate visual contrast, if it is lower than threshold, then re-adjust the change rate to realize closed loop refining, improve light intensity regulation accuracy.This method can improve the real-time sensing ability of ambient light.

The embodiment of the application provides a kind of absolute radiation calibration method of spaceborne micro-light load and related equipment.Therein, method includes: the multiple point light sources of different light source imaging area are carried out respectively spaceborne micro-light load entrance pupil radiance calculation, obtain multiple entrance pupil radiance value;The pixel of each point light source corresponding multiple remote sensing image pixel brightness value is accumulated, and multiple remote sensing image pixel brightness value sum is obtained;Based on entrance pupil radiance value and remote sensing image pixel brightness value sum, determine the radiation calibration point corresponding to each point light source;Linear fitting is carried out to multiple radiation calibration points, and the calibration function after fitting is obtained, and the calibration coefficient is determined based on the calibration function after fitting.The absolute radiation calibration of spaceborne micro-light load can be realized in the way of multiple-point calibration, compared with the way of single-point calibration in prior art, the calibration accuracy can be improved, and the demand of high-precision radiation calibration and radiation performance monitoring of spaceborne micro-light load can be met.

This application relates to a multi-view dynamic monitoring screen anti-leakage alarm method, system, and terminal, belonging to the technical field of information security. The method includes: acquiring video frames in front of the screen, the brightness of the screen's reflective area, and the ambient background brightness; calculating the device shape matching degree of a suspicious device based on the video frames; determining whether the device shape matching degree is greater than a first threshold; if so, obtaining the center coordinates of the suspicious device and the center coordinates of the screen's reflective area; calculating the Euclidean distance based on the center coordinates of both; tracking the movement speed of the suspicious object in consecutive Z frames based on the video frames; calculating the reflectivity coefficient of consecutive Z frames based on the brightness of the screen's reflective area and the ambient background brightness, and calculating the motion reflectivity correlation coefficient; determining whether the Euclidean distance is less than a second threshold and the motion reflectivity correlation coefficient is greater than a third threshold; if so, outputting a first threat value and triggering a level one alarm. This application has the beneficial effect of ensuring that screen information is not illegally photographed or stolen.

The invention relates to a method and device for automatically debugging brightness, display equipment and a storage medium. The method comprises the following steps: converting an input image into a grayscale image; calculating a brightness average value and a brightness maximum value of the grayscale image, and calculating a brightness difference value; determining a backlight brightness value through a backlight brightness calculation formula according to the brightness average value, the brightness difference value and the adjustable parameter; performing edge detection on the input image to identify an edge pixel region in the image; calculating a color difference value of two sides of the edge in the edge pixel area, and adjusting a pixel value of the edge pixel area when the color difference value is smaller than a sensing threshold value; according to a backlight brightness value, an S-shaped curve is used for carrying out pixel value mapping on the adjusted image data to obtain an output image, and by analyzing the brightness distribution, the contrast ratio and other characteristics of the image, on the premise of ensuring that the displayed image quality is acceptable, such as brightness, color accuracy, backlight brightness dynamic reduction and pixel signal compensation, the balance of image quality-power consumption is achieved.