WO2017028047A1 - Procédé et appareil d'extraction de modèles d'arrière-plan et dispositif de traitement d'image - Google Patents

Procédé et appareil d'extraction de modèles d'arrière-plan et dispositif de traitement d'image Download PDF

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Publication number
WO2017028047A1
WO2017028047A1 PCT/CN2015/087074 CN2015087074W WO2017028047A1 WO 2017028047 A1 WO2017028047 A1 WO 2017028047A1 CN 2015087074 W CN2015087074 W CN 2015087074W WO 2017028047 A1 WO2017028047 A1 WO 2017028047A1
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WIPO (PCT)
Prior art keywords
pixel
image
background model
pixel value
monitoring area
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PCT/CN2015/087074
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English (en)
Chinese (zh)
Inventor
杨兵兵
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富士通株式会社
杨兵兵
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Priority to PCT/CN2015/087074 priority Critical patent/WO2017028047A1/fr
Publication of WO2017028047A1 publication Critical patent/WO2017028047A1/fr

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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/20—Analysis of motion
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/14—Picture signal circuitry for video frequency region

Definitions

  • the present invention relates to the field of graphic image technology, and in particular, to a method and apparatus for extracting a background model and an image processing apparatus.
  • background images are widely used in the field of image monitoring and the like.
  • the difference between the current frame and the reference frame can be compared, thereby detecting a moving object.
  • the reference frame may be referred to as a "background image” or represented using a "background model.”
  • Embodiments of the present invention provide a method, an apparatus, and an image processing apparatus for extracting a background model. It is possible to reduce ghosting during image detection and to detect objects that move at a relatively small speed or are stationary for a period of time.
  • a method for extracting a background model includes:
  • a background model of the monitoring area is obtained according to a frequency of occurrence of a range of pixel values in the multi-frame image.
  • an apparatus for extracting a background model comprising:
  • An image acquisition unit that acquires a multi-frame image of the monitoring area
  • the model obtaining unit obtains a background model of the monitoring area according to a frequency of occurrence of a range of pixel values in the multi-frame image.
  • an image processing apparatus comprising the extraction means of the background model as described above.
  • a computer readable program wherein when the program is executed in an image processing apparatus, the program causes a computer to execute a background model as described above in the image processing apparatus Extraction method.
  • a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform an extraction method of a background model as described above in an image processing device.
  • An advantageous effect of the embodiment of the present invention is that a background model of the monitoring area is obtained according to the frequency of occurrence of the pixel value range in the multi-frame image.
  • FIG. 1 is a schematic diagram of a method for extracting a background model according to Embodiment 1 of the present invention
  • FIG. 2 is a diagram showing an example of a histogram for counting a certain pixel position according to Embodiment 1 of the present invention
  • FIG. 3 is another schematic diagram of a method for extracting a background model according to Embodiment 1 of the present invention.
  • FIG. 4 is a schematic diagram of an apparatus for extracting a background model according to Embodiment 2 of the present invention.
  • Figure 5 is another schematic diagram of an apparatus for extracting a background model according to Embodiment 2 of the present invention.
  • Fig. 6 is a block diagram showing the configuration of an image processing apparatus according to a third embodiment of the present invention.
  • ghosting may occur in a scene where, for example, when a moving object becomes a stationary object for a period of time (for example, a vehicle waiting for a traffic light), the moving object may be considered to be stationary and updated.
  • a moving object becomes a stationary object for a period of time (for example, a vehicle waiting for a traffic light)
  • the moving object may be considered to be stationary and updated.
  • ghosts will be left when the object moves again.
  • an image monitoring scene in the traffic field will be taken as an example for description.
  • a pixel value for a certain position of the monitoring area (for example, in units of pixels, hereinafter referred to as a pixel position) often appears in this scene (for example, the longest time of occurrence in a period of time), which can be regarded as the background pixel value of the position.
  • the present invention is not limited thereto, and can be applied to other scenarios.
  • Embodiments of the present invention provide a method for extracting a background model.
  • 1 is a schematic diagram of a method for extracting a background model according to an embodiment of the present invention. As shown in FIG. 1, the extraction method includes:
  • Step 101 Acquire a multi-frame image of a monitoring area.
  • Step 102 Obtain a background model of the monitoring area according to a frequency of occurrence of a range of pixel values in the multi-frame image.
  • video information including a plurality of frame images can be obtained by the camera.
  • the camera may be a camera for performing traffic image monitoring, and the monitoring area is continuously captured; however, the present invention is not limited thereto, and may be other image monitoring scenes.
  • steps 101 to 102 can be applied to the initialization process of the background model, and then the background model can be continuously updated.
  • the background model can be performed based on the multi-frame image in the video.
  • an initial background model M 0 can be obtained from 1000 frames of images, and then the background model is continuously updated to obtain background models M 1 , M 2 , . . . , Mi.
  • obtaining the background model of the monitoring area according to the frequency of occurrence of the pixel value range in the multi-frame image may include: counting, for each pixel position of the monitoring area, the pixel location in the Obtaining pixel value range frequency information corresponding to the pixel position in a pixel value in the multi-frame image; and determining a background model of the monitoring area according to the pixel value range frequency information.
  • the range of pixel values should be understood broadly, and the number of pixels in a certain range of pixel values may be plural or one.
  • the range of pixel values may be a case similar to 224-255, or may be a case where there is only a single pixel value such as 255. That is, a single pixel value can be used as a special case of a range of pixel values.
  • 1000 frames of images may be obtained first.
  • the corresponding pixel value in the 0th frame image is 255, and the corresponding pixel value in the first frame image is 80, in the second
  • the corresponding pixel value in the frame image is 255, ..., and the corresponding pixel value in the 999th frame image is 255.
  • the pixel value range frequency information can be obtained by performing statistics on the 1000 pixel values. For example, when the pixel value 255 in the image of a certain frame is obtained, the frequency corresponding to the range of pixel values (for example, 224-255) in which the pixel value 255 is located is incremented by one.
  • the pixel value range frequency information may be represented by a histogram; the abscissa of the histogram is a range of pixel values, and the ordinate of the histogram is a frequency.
  • the present invention is not limited thereto, and may be represented by other forms such as an array.
  • a pixel value range For example, 0-255 can be divided into 8 ranges, and each cylinder corresponds to a range of pixel values in the histogram. Each column has a width of 32 and the column height represents frequency.
  • the present invention is not limited thereto, and a specific form of a range of pixel values may be determined according to actual conditions.
  • FIG. 2 is a diagram showing an example of a histogram for counting a certain pixel position according to an embodiment of the present invention.
  • the abscissa of the histogram is a range of pixel values, and the ordinate of the histogram is frequency.
  • pixel values 81, 79 falling within the pixel value range 64-95
  • 162, 164, and 166 falling in the pixel value range 160
  • the three pixel value ranges (64-95), (160-191), and (224-255) correspond to a frequency of 200 Times, 100 times and 700 times.
  • a plurality of pixel values corresponding to the pixel value range may be averaged to obtain one pixel average value. Therefore, a plurality of pixel average values corresponding to a plurality of pixel value ranges respectively can be obtained, and a background model of the monitoring area is obtained according to the average value.
  • the pixel value range 64-95 has pixel values 81 and 79, then the pixel value range 64-95 can be calculated corresponding to the average value 80; the pixel value range 160-191 has pixels For values 162, 164, and 166, a pixel value range 160-191 corresponding to the average value 164 can be calculated; with pixel values 253 and 255 within the pixel value range 224-255, a pixel value range 224-255 corresponding to the average value 254 can be calculated.
  • the above only schematically illustrates how to calculate the background pixel value.
  • the present invention is not limited thereto, and may be appropriately modified or adjusted. For example, it is possible to calculate only the range of pixel values of the previous one or more frequencies.
  • the plurality of pixel average values are weighted to obtain the background model.
  • the present invention is not limited thereto, and the background model may be constructed using these pixel average values in other ways.
  • the average value of the pixel values with the most occurrences (represented by hiss_max_average) and the average value of the pixel values of the second most frequent occurrence (represented by hiss_secondary_average) may be used as background pixel values. This makes the background model more accurate and more tolerant of noise.
  • one or more frames of the new image of the monitoring area may be acquired to replace one or more old images in the multi-frame image; and the monitoring area is paired according to each new image or old image.
  • the background pixel values are updated.
  • FIG. 3 is another schematic diagram of a method for extracting a background model according to an embodiment of the present invention, schematically showing a case of initializing a background model and updating a background model.
  • the extraction method includes:
  • Step 301 Acquire a multi-frame image of a monitoring area.
  • Step 302 for each pixel position of the monitoring area, counting the pixel position in the multi-frame image a pixel value to obtain a pixel value range frequency information corresponding to the pixel position;
  • Step 303 Determine an initial background model according to the pixel value range frequency information.
  • a queue of length 1000 can be predefined, and 1000 frames of images are placed in the queue. Then, for each pixel position of the monitoring area, when the pixel value of the pixel position in a certain frame image of the 1000 frames is obtained, the frequency corresponding to the pixel value range in which the pixel value is located is incremented by one.
  • multiple frames may be acquired first and then statistics may be performed; or statistics may be performed after each frame is acquired, and then the information of the frame may be pushed into a queue to implement first-in-first. Out.
  • Step 304 Acquire a new image of a frame of the monitoring area
  • the information of the multi-frame image may be organized in the form of a queue, and after obtaining a new image of one frame, the old image of the first obtained frame may be replaced. Therefore, in combination with other factors, fast calculation can be performed to reduce the calculation time; however, the present invention is not limited thereto, and for example, it is also possible to obtain statistics and update after multiple frames.
  • Step 305 Update a background pixel value of the monitoring area according to the new image and the old image.
  • the method may include: for each pixel position of the monitoring area, subtracting a frequency corresponding to a range of pixel values of the pixel position in the old image by 1, and placing the pixel position in the new The frequency corresponding to the range of pixel values in the image is increased by one.
  • the pixel position corresponding to the pixel value in the image of the first frame may be corresponding to the pixel value range.
  • the frequency is decremented by 1, and the frequency corresponding to the pixel value range in which the pixel position in the image of the 1001th frame is located is incremented by one.
  • step 306 it is determined whether to continue the update; if yes, step 304 is performed to retrieve a new image for updating.
  • a frame image update is taken as an example, but the present invention is not limited thereto; for example, statistics and update of pixel value frequency information may be continuously performed, when a preset condition is reached (for example, a statistical N frame image, or After the preset time T) is executed, the background pixel value is updated and the background model is updated.
  • a preset condition for example, a statistical N frame image, or After the preset time T
  • the background pixel value is updated and the background model is updated.
  • the background model of the monitoring area is obtained according to the frequency of occurrence of the pixel value range in the multi-frame image.
  • the embodiment of the present invention provides a device for extracting a background model, and the same content as that of Embodiment 1 will not be described again.
  • the background model extraction apparatus 400 includes:
  • the image obtaining unit 401 acquires a multi-frame image of the monitoring area
  • the model obtaining unit 402 obtains a background model of the monitoring area according to a frequency of occurrence of a range of pixel values in the multi-frame image.
  • the image acquisition unit 401 can obtain a multi-frame image according to the video information obtained by the camera.
  • FIG. 5 is another schematic diagram of an apparatus for extracting a background model according to an embodiment of the present invention.
  • the background model extraction apparatus 500 includes an image acquisition unit 401 and a model obtaining unit 402, as described above.
  • the model obtaining unit 402 may include:
  • a statistic unit 501 for each pixel position of the monitoring area, counting pixel values of the pixel position in the multi-frame image to obtain pixel value range frequency information corresponding to the pixel position;
  • the determining unit 502 determines the background pixel value according to the pixel value range frequency information.
  • the pixel value range frequency information may be represented by a histogram; wherein the abscissa of the histogram is a range of pixel values, and the ordinate of the histogram is frequency, but the invention is not limited thereto.
  • the statistic unit 501 is specifically configured to: when obtaining the pixel value of the pixel position in a certain frame image, add a frequency corresponding to the pixel value range of the pixel value 1.
  • the present invention is not limited thereto, and other statistical methods may be employed, for example.
  • the determining unit 502 is specifically configured to: average a plurality of pixel values corresponding to the plurality of pixel value ranges, and obtain a plurality of pixel average values corresponding to the plurality of pixel value ranges; The pixel average is obtained for the background model.
  • the determining unit 502 may be further configured to: perform weighting processing on the average value of the pixels to obtain the background model.
  • the present invention is not limited thereto, and the background model may be constructed in other ways.
  • the image obtaining unit 401 may be further configured to acquire one or more new frames of the monitoring area to replace one or more old images in the multi-frame image;
  • the extraction device 500 of the background model may further include:
  • the model updating unit 503 updates the background model of the monitoring area according to each frame of new image or old image.
  • the pixel value updating unit 503 may be specifically configured to: for each pixel position of the monitoring area, the frequency corresponding to the pixel value range of the pixel position in each old image of each frame The degree is decremented by 1, and the frequency corresponding to the range of pixel values of the pixel position in the new image of each frame is incremented by one.
  • the present invention is not limited thereto, and other updating methods may be employed.
  • the background model of the monitoring area is obtained according to the frequency of occurrence of the pixel value range in the multi-frame image.
  • An embodiment of the present invention provides an image processing apparatus, where the image processing apparatus includes: a background model extraction apparatus according to Embodiment 2.
  • Fig. 6 is a block diagram showing the configuration of an image processing apparatus according to an embodiment of the present invention.
  • the image processing apparatus 600 may include a central processing unit (CPU) 100 and a memory 110; the memory 110 is coupled to the central processing unit 100.
  • the memory 110 can store various data; in addition, a program for information processing is stored, and the program is executed under the control of the central processing unit 100.
  • the functionality of the background model's extraction device 400 or 500 can be integrated into the central processor 100.
  • the central processing unit 100 may be configured to implement the extraction method of the background model as described in Embodiment 1.
  • the extraction device 400 or 500 of the background model may be configured separately from the central processing unit.
  • the extraction device 400 or 500 of the background model may be configured as a chip connected to the central processing unit 100 through the central processing unit. The functions of the extraction device 400 or 500 that implement the background model are controlled.
  • the image processing apparatus 600 may further include: an input and output unit 120, a display unit 130, and the like; wherein the functions of the above components are similar to those of the prior art, and are not described herein again. It is to be noted that the image processing apparatus 600 does not necessarily have to include all of the components shown in FIG. 6; in addition, the image processing apparatus 600 may further include components not shown in FIG. 6, and reference may be made to the related art.
  • Embodiments of the present invention also provide a computer readable program, wherein when the program is executed in an image processing apparatus, the program causes a computer to perform extraction of a background model as described in Embodiment 1 in the image processing apparatus method.
  • An embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer is The reading program causes the computer to execute the extraction method of the background model as described in Embodiment 1 in the image processing apparatus.
  • the above apparatus and method of the present invention may be implemented by hardware or by hardware in combination with software.
  • the present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps.
  • the present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, or the like.
  • One or more of the functional blocks described in the figures and/or one or more combinations of functional blocks may be implemented as a general purpose processor, digital signal processor (DSP) for performing the functions described herein.
  • DSP digital signal processor
  • ASIC application specific integrated circuit
  • FPGA field programmable gate array
  • One or more of the functional blocks described with respect to the figures and/or one or more combinations of functional blocks may also be implemented as a combination of computing devices, eg, a combination of a DSP and a microprocessor, multiple microprocessors One or more microprocessors in conjunction with DSP communication or any other such configuration.

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  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
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Abstract

La présente invention concerne un procédé et un appareil d'extraction de modèles d'arrière-plan et un dispositif de traitement d'image. Le procédé d'extraction consiste en : l'acquisition d'une image multitrame d'une zone surveillée ; et l'obtention d'un modèle d'arrière-plan de la zone surveillée en fonction d'une fréquence de survenance des plages de valeur de pixels dans l'image multitrame. En conséquence, un phénomène d'image fantôme survenant pendant le processus de détection d'image peut être réduit et des objets présentant une vitesse de déplacement relativement faible ou restant fixes pendant une période de temps particulière peuvent être détectés, tout en obtenant en même temps une plus grande précision de détection d'image et une meilleure capacité de tolérance de bruit.
PCT/CN2015/087074 2015-08-14 2015-08-14 Procédé et appareil d'extraction de modèles d'arrière-plan et dispositif de traitement d'image WO2017028047A1 (fr)

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CN110033425A (zh) * 2018-01-10 2019-07-19 富士通株式会社 干扰区域检测装置及方法、电子设备
CN111080583A (zh) * 2019-12-03 2020-04-28 上海联影智能医疗科技有限公司 医学图像检测方法、计算机设备和可读存储介质
CN111179299A (zh) * 2018-11-09 2020-05-19 珠海格力电器股份有限公司 一种图像处理方法及装置
CN112084880A (zh) * 2020-08-14 2020-12-15 江铃汽车股份有限公司 一种图像处理方法、装置、存储介质及设备
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CN112084880A (zh) * 2020-08-14 2020-12-15 江铃汽车股份有限公司 一种图像处理方法、装置、存储介质及设备

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