578 results about "Absolute difference" patented technology

In a method of image subtraction a series of frames of a subject are taken using a video camera The subject is illuminated in a manner so that illumination is alternately on then off for successive fields within the image frame. A single frame is grabbed and an absolute difference between the odd field and the even field within that single image frame is determined. The resulting absolute difference image will represent the subject as illuminated by the system illumination only, and not by any ambient illumination, and can then be used to identify the subject in the image.

This invention relates to a memory device and the like that are preferably applied to a case where motion vector is detected using a block matching. Pixel data of a first frame (a reference frame) is stored in a unit A of memory cell array portion 20a in straight binary format. Pixel data of a second frame (a search frame) is stored in a unit B of memory cell array portion 20b in two's complement format. The units A and B have a plurality of memory cells, respectively. Word lines WL related to the pixel data of the first and second frames are simultaneously activated so that charges accumulated in capacitors of each of the memory cells can be combined along one bit line BL. A/D converter 53 outputs a digital signal (absolute difference value) having a value that corresponds to a total amount of charges. When reading the pixel data, a subtraction and a conversion into the absolute difference value are simultaneously performed.

There is described a device for converting an input signal having a given input voltage (Vbat) value (Vbat) into an output signal having an output voltage (Vout) (Vout) different from the input voltage (Vbat). The device comprises a main module (56), arranged between an input terminal (54) and a first circuit node (N1), The device is adapted to output at the first circuit node (N1) a pulse-width-modulated (PWM) signal switching between a first voltage value and a second voltage value, defining a switching range (SR(i)), by switching successively between a first mode of operation and a second mode of operation. The switching range (SR(i)) of the pulse width modulation (PWM) has an amplitude, calculated as the absolute difference between the first and the second voltage value, inferior or equal to Vout half the input voltage (Vbat).

A method and a device for motion estimated and compensated Field Rate Up-conversion (FRU) for video applications is disclosed and claimed. The invention provides for dividing an image field to be interpolated into a plurality of image blocks, where each image block includes a respective set of image elements of the image field. In one embodiment, for each image block of a subset of image blocks, a group of neighboring image blocks is selected. A motion vector for the image block is estimated that describes the movement of the image block from a previous image field to a current image field on the basis of predictor motion vectors associated to the group of neighboring image blocks. Each image element of the image block is determined by interpolation of two corresponding image elements in the previous and current image fields related by the estimated motion vector. To estimate a motion vector, the invention provides for applying each of the predictor motion vectors to the image block to determine a respective pair of corresponding image blocks in the previous and current image fields. For each of the pairs of corresponding image blocks, an error function which is the Sum of luminance Absolute Difference (SAD) between corresponding image elements in the pair of corresponding image blocks is evaluated. For each pair of the predictor motion vectors, a degree of homogeneity is also evaluated, followed by the application of a fuzzy rule having an activation level that is proportional to the degree of homogeneity of the pair of predictor motion vectors and the error functions of the pair of predictor motion vectors. An optimum fuzzy rule having the highest activation level is selected, from which the best predictor motion vector is determined, having the smaller error function of the pair associated to the optimum fuzzy rule. In most cases, the motion vector for the image block is estimated on the basis of the best predictor motion vector.

An image interpolation method comprises searching a motion vector from different pairs of blocks on a first and a second reference image symmetrically, extracting a first and a second image block from the first and the second reference image, respectively, the first and the second image block being located by the motion vector, determining a region determination threshold using an absolute difference between paired opposite pixels of the first and the second image block, extracting from each of the first and the second image block a first pixel region that the absolute difference is smaller than the region determination threshold, and obtaining a pixel value of a second pixel region of the to-be-interpolated block from a pixel value of the first pixel region of each of the first and the second image block, the second pixel region corresponding to the first pixel region.

A motion vector detection method comprises extracting a first block including a plurality of pixels from a first frame of the image, detecting a second block from a plurality of blocks of a second frame of the image by block matching, the second block including the maximum number of pixels each indicating an absolute difference value not more than a first threshold with respect to each of the pixels of the first block, and computing a first motion vector between the first block and the second block.

A wireless radio frequency positioning method adopting region division algorism comprises the steps of: arranging reader at the boundary of an object region, distributing the reference labels as a rectangular grid type in the indoor object region; arranging an object with a radio frequency label in the object region, using each reader and their antenna to check the electromagnetic wave of each radio frequency label, transmitting the measured reference label and the radio frequency signal intensity value (RSSI value) of the object label to a host computer; at the host computer, comparing the RSSI absolute difference of each reference label and object label to find four nearest reference labels near the object, preliminarily determining the effective positioning region of the object; using the region division algorism to reduce the effective positioning region formed by the nearest reference labels to 1/8; using the residual weighting algorism between different reference labels to attain the position of the object. The method has the advantages of low power consumption and high positioning accuracy.

The invention provides a statistical method for the high-density crowd flow, which comprises the following steps: selecting a supervision region image from video images which supervise mobile crowd in real time; converting a colorful supervision region image into a gray level video image; comparing the absolute difference of pixels on corresponding positions among three adjacent frames in an input gray level video image sequence; carrying out thresholding to an obtained detection result to obtain a binarization image so as to extract the moving crowd in the image; the current supervision region image is subjected to abnormality detection; setting a region of interest, and collecting pixels from the region of interest according to the binarization image; and according to the correspondenceof a pixel number and a number, calculating the total number passing through the supervision region within unit time so as to calculate the crowd flow in real time. According to the statistical method, the high-density migrant crowd advancing to one direction can be subjected to flow statistics under the complex background.

The invention discloses a detection method for moving targets in images based on block division. At first, the size of each pixel sub-block when images to be detected are divided into a plurality of pixel sub-blocks is preset, then an area image of a present frame to be detected is divided into corresponding pixel sub-blocks, then a frame is selected as a reference frame from frame images before the present frame or pre-established background images, the absolute difference and sum of pixels of corresponding pixel sub-blocks of area images of the reference frame and the present frame are respectively calculated according to the positions of the corresponding pixel sub-blocks of the area image of the present frame, then the absolute difference and sum of the pixels is compared with a preset moving threshold to find pixel sub-blocks which possibly have moving targets, finally the pixel sub-blocks which possibly have moving targets are statistized and analyzed to judge whether moving targets exist in the area image of the present frame to be detected, thus the video coding process and the motion detection process can be organically combined to effectively decrease the total calculation quantity of video coding and motion detection.

A scaleable macro block rate control method particularly well-suited for MPEG video. There is provided a method to easily derive a quantization parameter (QP) value using information such as bit usage, previous QP values and SAD values from the past encoded and future frames. The method utilizes quantization estimation techniques based on statistical relationships between different intensity measures, such as distortion intensity, absolute difference intensity and mean of absolute difference intensity. The method is well-suited to applications utilizing MPEG video such as MPEG-1, MPEG-2, MPEG-4, JVT/H.264 standards and so forth.

The invention discloses a three-dimensional image objective quality evaluation method, which comprises the following steps: respectively carrying out wavelet transformation on left view point images and right view point images of undistorted three-dimensional images and distorted three-dimensional images; extracting characteristic values of each sub band; carrying out similarity measurement on the characteristic values; determining the weight factors of each sub band by contrast sensitive functions; then, realizing the evaluation on the three-dimensional sensing quality through evaluating the absolute difference image similarity of left images and right images of the undistorted three-dimensional images and the distorted three-dimensional images; and finally, combining the quality of the left images and the right images and the three-dimensional sensing quality to obtain the final evaluation results of the three-dimensional image quality. The invention has the advantages that the human eye visual characteristics such as human visual sensitivity bandpass, the multi-channel effect, the three-dimensional sensation and the like are utilized, the three-dimensional sensation is simultaneously evaluated on the basis of the evaluation on the quality of the left view point images and the right view point images, the influence of the three-dimensional sensation in the three-dimensional images on the final three-dimensional image quality is merged into an evaluation model, and the correlativity of the objective evaluation results and the subjective sensation is improved.

The invention provides a self-adaptive cruise control method and device of a vehicle, and the vehicle, and relates to the field of vehicles. The method comprises the following steps: detecting whether an obstacle exists in front of the vehicle; when the obstacle is detected in front of the vehicle, controlling self-adaptive cruise control of the vehicle according to the distance between the obstacle and the vehicle, the absolute difference between the moving speed of the obstacle and a preset vehicle speed of the vehicle and the closet distance between the obstacle and the lane line of a lane where the vehicle is. Therefore, an effective control strategy is provided for the self-adaptive cruise control of the vehicle, so that the traffic safety is guaranteed to a certain extent.

An earth boring drill bit is constructed having rotatable cutter for forming a borehole in earth. At least one circumferential row of cutting elements is optimized to create overbreak of rock and eliminate tracking, wherein selected pitches have mathematically determined pairs and the absolute difference between the selected pitch and its pair is greater than 10% of the difference between maximum and minimum pitch for that circumferential row. Furthermore, cutting elements are placed along pre-selected generatrices with deviation from said generatrices, which is less than half the maximum pitch of circumferential rows occupied by said cutting element. The present invention eliminates tracking and reduces detrimental axial resonance frequency vibration while reducing cutting element count, including tungsten-carbide inserts, as compared to conventional roller cutter drill bits used for oil, gas and shot hole drilling wells and simultaneously increases footage drilled, drilling speed, and durability.

An apparatus generally having a first circuit, a second circuit and a third circuit is disclosed. The first circuit may be configured to generate a plurality of difference values by calculating an absolute difference between each pixel from a current block and a corresponding pixel from a reference block substantially simultaneously. The second circuit may be configured to generate a plurality of sum values by adding the difference values. The third circuit may be configured to generate at least one motion vector in response to the sum values.

The invention discloses a three-dimensional video quality evaluation method which relates to the field of digital video. The three-dimensional video quality evaluation method comprises the steps of: obtaining a gradient structure similarity index of each subblock; extracting brightness information, movement information and structure information of each subblock on the basis of a human visual system, further figuring out a quality weight of each subblock; respectively obtaining a single-frame quality of a left visual point or right visual point by combining with the gradient structure similarity index and the quality weight of each subblock; obtaining a single-visual point video quality through the single-frame quality; based on the human three-dimensional visual system, endowing different weights to the video qualify of the left visual point or right visual point to obtain a quality value of a three-dimensional video; calculating an absolute difference chart of each frame of image of an original three-dimensional video and a distortion three-dimensional video; and calculating a peak signal to noise ratio of an original video absolute difference chart and a distortion video absolute difference chart to be used as a three-dimensional value of the three-dimensional video. According to the three-dimensional video quality evaluation method, the quality of the three-dimensional video is completely evaluated, and thus the evaluation quality is improved.

A dynamic road surface detecting method based on a three-dimensional sensor is provided. The three-dimensional sensor receives a plurality of laser-emitting points reflected from a road surface to generate a plurality of three-dimensional sensor scan point coordinates which is transmitted to a point cloud processing module. The point cloud processing module transforms the three-dimensional sensor scan point coordinates to a plurality of vehicle scan point coordinates according to a coordinate translation equation, and then transforms a plurality of vehicle coordinate height values of the vehicle scan point coordinates to a road surface height reference line according to a folding line fitting algorithm. An absolute difference of two scan point height values of any two adjacent scan points on each of the scan lines is analyzed to generate a discontinuous point. The point cloud processing module links the discontinuous points to form a road boundary.

A method for eliminating noise from an image generated by an image sensor, includes: setting a group of pixels arranged in a square matrix and including a central pixel intended to eliminate the noise in the image and peripheral pixels arranged around the central pixel; obtaining absolute difference values between a luminance value of the central pixel and a luminance value of the peripheral pixels according to directionalities of the peripheral pixels about the central pixel; comparing the obtained absolute difference values with first critical values to determine a region to which the central pixel belongs; when the determined region is the contour region, eliminating noise of the group of the pixels according to directionality of the contour; and when the determined region is the noise region, eliminating the noise of the group of the pixels according to a noise level of the group of the pixels.

A positioning method which is based on the wireless radio frequency identification technology comprises the steps that readers are arranged at the boundary of a zone to be monitored; reference tags are fixed at an indoor zone to be monitored in a rectangular grid type; when an object to be monitored with radio-frequency tags is arranged in the zone to be monitored, each of the readers detects the electromagnetic wave of each radio-frequency tag through the antenna of each of the readers, the radio-frequency signal intensity values of the reference tags which are obtained by the measurement and the tags of the object to be tested are sent to an upper computer; the upper computer compares the absolute difference values of the radio-frequency signal intensity of each of the reference tags and the tags of the object to be tested to determine a plurality of nearest reference tags of the object to be tested; each nearest reference tag and the calculated position of the object to be tested are obtained through the trilateration method, and the average measurement error of a system is obtained by comparing the calculated positions and the actual positions of the nearest reference tags; the calculated positions of the object to be tested adds the average measurement error to obtain the position coordinates of the object to be tested. By utilizing the method of the invention, a positioning system has good accuracy and real-time in the aspect of position induction.

An MPEG decoder verifies a previous video packet by calculating the sum-of-the-absolute differences (SAD) for macroblock boundaries. When a macroblock counter goes off count, the macroblocks can be placed in the wrong relative locations in a frame. Image shapes are sliced when macroblock misplacement occurs, creating many new bisecting edges along macroblock boundaries. These image discontinuities along macroblock boundaries have a large SAD for pixels on either side of the macroblock boundary. The SAD is generated along the left and upper edges of a current macroblock, and a maximum SAD of all macroblocks in the previous video packet is generated. When the maximum SAD is above a threshold, the macroblock counter is likely to be in error, and the macroblock counter is reloaded with the header macroblock number from the next packet header. When the SAD is below threshold, a mis-matching header macroblock number is ignored.

A method of generating a value for a missing pixel “x” by determining a “least harmful” local edge direction between pixels, or sub-pixels, on substantially opposing sides of the missing pixel, and interpolating the difference to arrive at a value for pixel “x”. The method involves generating sub-pixel values for locations within neighboring pixels, the sub-pixels may comprise half-pixels, quarter-pixels, three-quarter pixels, and so forth, wherein any fractional pixel quantity may be created. Absolute difference values are calculated between neighboring pixels, or sub-pixel values, to determine a least harmful local edge direction along which a value is generated for pixel “x” by interpolation.