CN103778629A - Background model real-time updating method for non-coherent radar image - Google Patents

Background model real-time updating method for non-coherent radar image Download PDF

Info

Publication number
CN103778629A
CN103778629A CN201410017422.XA CN201410017422A CN103778629A CN 103778629 A CN103778629 A CN 103778629A CN 201410017422 A CN201410017422 A CN 201410017422A CN 103778629 A CN103778629 A CN 103778629A
Authority
CN
China
Prior art keywords
background model
pixel
sample
new samples
radar image
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201410017422.XA
Other languages
Chinese (zh)
Inventor
陈唯实
李敬
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Academy of Civil Aviation Science and Technology
Original Assignee
China Academy of Civil Aviation Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Academy of Civil Aviation Science and Technology filed Critical China Academy of Civil Aviation Science and Technology
Priority to CN201410017422.XA priority Critical patent/CN103778629A/en
Publication of CN103778629A publication Critical patent/CN103778629A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Radar Systems Or Details Thereof (AREA)

Abstract

The invention discloses a background model real-time updating method for a non-coherent radar image and the method is used for low-altitude airspace security monitoring. In the method, a background model sample set is established for each pixel in a radar image and in a background model updating process, the value of each pixel in a current frame of image is compared with the background model sample set of the pixel of a current background model are compared and if the pixel values belong to a sample of the background model, then the pixel values replace randomly a specific sample in the current background model. At the same time, the pixel values are used to update randomly a background model sample set of a specific adjacent-domain pixel. The update cycle of the background model also adopts a random setting method. The background model real-time updating method for the non-coherent radar image prolongs the time that each sample persists in a background model set under a condition that the number of background model samples is kept unchanged so that time coverage range of the background model samples is expanded.

Description

A kind of background model real time updating method of non-coherent radar image
Technical field
The present invention relates to a kind of background model real time updating method of non-coherent radar image, belong to low altitude airspace security monitoring technical field, relate to radar image and process and target detection.
Background technology
Once non-coherent radar have cost low, set up conveniently, the feature such as working alone property is strong, be the important means of spatial domain security monitoring.Non-coherent radar itself does not possess the function that moving-target detects, ripe radar surveillance system adopts image pick-up card that scope indicating image is transferred to computing machine conventionally, by rear end, the algorithm of target detection based on image is processed it again, therefrom extracts moving-target information.Background differential technique is the most frequently used moving target detection technique.But, because the region of system monitoring is low altitude airspace, background environment complexity, noise is strong, and background object glint is larger, and has certain random character.Therefore, set up background model accurately, and adopt suitable method to carry out real-time update to it, become the key that improves target detection ability.
Traditional background model update method, conventionally utilize the new background sample of pixels of extracting in current frame image to remove to replace the longest sample of retention time in original background model, the time of causing each sample to retain in background model is identical, has limited the time coverage of background model sample.
Summary of the invention
The object of the present invention is to provide a kind of background model real time updating method of non-coherent radar image, the method is applicable to detect based on the moving-target of non-coherent radar image, has widened the time coverage of background model sample.
The background model real time updating method of non-coherent radar image of the present invention, comprises the steps:
Step 1, for the each pixel in radar image is set up background model;
In radar image, gray-scale value corresponding to each pixel (x, y) represented by v (x, y), uses v irepresent i background model sample, the background model M (x, y) of each pixel (x, y) is expressed as by N the background model sample set extracting in N two field picture before:
M(x,y)={v 1,v 2,...,v N} (1)
N background model sample in formula (1) set, initially obtains: for i (1≤i≤N) two field picture in radar image sequence, be communicated with neighborhood N from 8 of pixel (x, y) by the following method gin (x, y), extract i background model sample v i:
Figure BDA0000457102150000011
Wherein, coordinate
Figure BDA0000457102150000012
at neighborhood N gin (x, y), select at random,
Figure BDA0000457102150000013
denotation coordination the gray-scale value at place.
Step 2, reads a frame radar image, to the new samples classification of each pixel;
According to the background model M (x, y) of pixel (x, y), the new samples v (x, y) of pixel in current frame image is classified, specifically: centered by v (x, y), R is radius, set up spherical territory S r(v (x, y)), if the sample number in the common factor of the background model sample set of this spherical territory and M (x, y) is not less than threshold value # min, new samples v (x, y) is judged as to background model sample, otherwise new samples is judged as foreground target.The common factor of spherical territory and background model sample set is expressed as:
#{S R(v(x,y))∩{v 1,v 2,...,v N}} (3)
Step 3, for the new samples that is judged to be background model, upgrades the background model of respective pixel;
For the new samples v (x, y) that is judged to be background model, between generation 0~1, random decimal θ, if θ is greater than threshold value T, upgrades pixel (x, y) background model, otherwise does not upgrade.
In the time carrying out background model renewal, generate the random integers i between 0~N, and replace i sample v in background model with new samples v (x, y) i.
Step 4, for the new samples that is judged to be background model, upgrades neighborhood territory pixel sample;
For the new samples v (x, y) that is judged to be background model, random decimal θ between generation 0~1, if θ is greater than threshold value T, is communicated with pixel background model in neighborhoods to 8 of pixel (x, y) and upgrades, otherwise do not upgrade.
When carrying out in neighborhood pixel background model while upgrading, select at random the pixel coordinate (x in 8 connection neighborhoods nG, y nG), generate the random integers i between 0~N, with new samples v (x, y) replacement pixel (x nG, y nG) background model in i sample v i.
The background model real time updating method of non-coherent radar image provided by the invention, compared with prior art, in the situation that keeping background model sample size constant, extend the time that each sample retains in background model set, widen the time coverage of background model sample.
Accompanying drawing explanation
Fig. 1 is the schematic flow sheet of the background model real time updating method of non-coherent radar image of the present invention;
Fig. 2 is the original non-coherent radar image of a frame and certain location of pixels of the embodiment of the present invention.
Embodiment
Background model real time updating method the present invention being proposed below in conjunction with the result of certain non-coherent radar image sequence in accompanying drawing illustrates and describes.
In non-coherent radar background, comprise a large amount of stationary objects, wherein major part belongs to non-rigid targets (woods, meadow, the water surface etc.), echo strength big rise and fall, and background edge noise jamming is strong, detects and causes difficulty to low altitude small target.The inventive method is set the background model update cycle at random, and replace at random the sample in background model, extended the retention time of each sample in background model, as shown in Figure 1, the background model real time updating method of non-coherent radar image of the present invention comprises that concrete steps are as follows to its flow process:
Step 1, background model initializing; For the each pixel in radar image is set up background model.
First, in radar image, gray-scale value corresponding to each pixel (x, y) represented by v (x, y), and demarcates each background model sample v with index i i, i is integer and 1≤i≤N, the background model M (x, y) of each pixel (x, y) forms background model sample set by N the background model sample extracting in multiple image before:
M(x,y)={v 1,v 2,...,v N} (1)
For the first two field picture in radar image sequence (time t=0), can be communicated with neighborhood N from 8 of pixel (x, y) gin (x, y), extract background model sample, be expressed as M 0(x, y):
Figure BDA0000457102150000031
Coordinate in above formula
Figure BDA0000457102150000032
can be at neighborhood N gin (x, y), select at random the gray-scale value of certain pixel
Figure BDA0000457102150000033
may repeatedly be selected, also may be never selected.V 1be initially M 0(x, y).
Continue to read N-1 frame radar image, in every two field picture, identical with method shown in formula (2), obtain the background model sample value of pixel (x, y) in every two field picture.For i (1≤i≤N) two field picture in radar image sequence, be communicated with neighborhood N from 8 of pixel (x, y) gin (x, y), extract i background model sample v i:
Figure BDA0000457102150000034
finally obtain the background model suc as formula the pixel (x, y) shown in (1).
As shown in Figure 2, image size is 456 × 456 to the original non-coherent radar image of one frame, and true origin is in the image upper left corner, and to the right, vertically downward, in figure, the pixel coordinate of " * " position is (138,360) to Y-axis to X-axis level.The background model sample set of this pixel amounts to and comprises 10 samples, i.e. N=10, and the gray-scale value that each sample is pixel, background model is as follows:
M(138,360)={10,10,12,24,22,11,12,34,12,26} (3)
Step 2, reads a frame radar image, to the new samples classification of each pixel.
According to the current background model M (x, y) of pixel (x, y), the new samples v (x, y) of pixel (x, y) in current frame image is classified, judge whether new samples belongs to background model sample set.Centered by v (x, y), R is radius, sets up spherical territory S r(v (x, y)), R is integer.If the sample number in the common factor of this spherical territory and background model sample set is not less than threshold value # min, the new samples v (x, y) of this pixel is judged as to background model sample, proceed step 3 and 4; Otherwise the new samples v (x, y) that judges this pixel is not background model sample, be foreground target, do not carry out step 3 and 4 below.The common factor of spherical territory and background model sample set is expressed as:
#{S R(v(x,y))∩{v 1,v 2,...,v N}} (4)
In the embodiment of the present invention, the grey scale pixel value of establishing current frame image " * " position coordinate is v (138,360)=15, and centered by this new samples, R=5 is radius, sets up spherical territory S r=5(v (138,360)), threshold value # min=5, the common factor of this spherical territory and background model sample set is
#{S R=5(v(138,360))∩M(138,360)}={10,10,12,11,12,12} (5)
In occuring simultaneously, have 6 samples, be greater than threshold value # minso this sample is background sample.
Step 3, for the new samples that is judged to be background model, upgrades the background model of respective pixel.In renewal, realize update cycle and the more random setting of new samples.
For the new samples v (x, y) that is judged to be background model, determine whether to use it for background model renewal by generating the method for random decimal θ between 0~1.If θ is greater than threshold value T, pixel (x, y) background model is upgraded, otherwise do not upgraded.Threshold value T is set by the user, and is the data between 0~1.
In the time carrying out background model renewal, adopt equally random device to select more new samples.Generate the random integers i between 0~N, and replace i sample v in background model with v (x, y) i.
In the embodiment of the present invention, establish threshold value T=0.5, the random decimal of generation is θ=0.68, background model is upgraded, and replaces certain sample in original background model with new samples v (138,360)=15.Generate random integers i=6, replace the 6th sample of background model, the background model after renewal is
M(138,360)={10,10,12,24,22,15,12,34,12,26} (6)
Step 4, for the new samples that is judged to be background model, upgrades neighborhood territory pixel sample.
For the new samples that is judged to be background model, can be used for equally upgrading the background model that 8 of pixel (x, y) is communicated with neighborhood.
The setting of update cycle is identical with step 3, adopts the method that generates random decimal between 0~1 to judge whether to upgrade.In the embodiment of the present invention, the random decimal of establishing generation is θ=0.52, is greater than threshold value T=0.5, upgrades neighborhood territory pixel background model with new samples v (138,360)=15.
The random method of same employing selects to need the neighborhood territory pixel position and replacement sample of renewal.If (x nG, y nG) be the pixel coordinate in 8 connection neighborhoods, comprise (x-1, y-1), (x-1, y), (x-1, y+1), (x, y-1), (x, y+1), (x+1, y-1), (x+1, y) and (x+1, y+1).Random definite neighborhood coordinate (x nG, y nG) afterwards, identical with step 3, generate the random integers i between 0~N, and with v (x, y) replacement pixel (x nG, y nG) background model in i sample v i.
In the embodiment of the present invention, establish the neighborhood territory pixel coordinate (x that random generation need be upgraded nG, y nG)=(138,361), the original background model of this pixel is:
M(138,361)={15,12,14,26,26,17,22,28,22,28} (7)
Generate random integers i=9, replace the 9th sample of this pixel background model, the background model after renewal is
M(138,361)={15,12,14,26,26,17,22,28,15,28} (8)
Utilizing present frame radar image to carry out after background model renewal, can continue to read next frame radar image, then go to step 2 continuation and carry out.

Claims (1)

1. a background model real time updating method for non-coherent radar image, is characterized in that, comprises the steps:
Step 1, for the each pixel in radar image is set up background model;
In radar image, gray-scale value corresponding to each pixel (x, y) represented by v (x, y), uses v irepresent i background model sample, the background model M (x, y) of each pixel (x, y) is expressed as by N the background model sample set extracting in N two field picture before:
M(x,y)={v 1,v 2,...,v N} (1)
N background model sample in formula (1) set, initially obtains: for i (1≤i≤N) two field picture in radar image sequence, be communicated with neighborhood N from 8 of pixel (x, y) by the following method gin (x, y), extract i background model sample v i:
Figure FDA0000457102140000011
Wherein, coordinate
Figure FDA0000457102140000012
at neighborhood N gin (x, y), select at random,
Figure FDA0000457102140000013
denotation coordination the gray-scale value at place;
Step 2, reads a frame radar image, to the new samples classification of each pixel;
For pixel (x, y), according to corresponding background model M (x, y), the new samples v (x, y) of pixel in current frame image is classified, specifically: centered by v (x, y), R is radius, set up spherical territory S r(v (x, y)), if the sample number in the common factor of the background model sample set of this spherical territory and M (x, y) is not less than threshold value # min, new samples v (x, y) is judged as to background model sample, otherwise new samples is foreground target;
Step 3, for the new samples that is judged to be background model, upgrades the background model of respective pixel;
For the new samples v (x, y) that is judged to be background model, between generation 0~1, random decimal θ, if θ is greater than threshold value T, upgrades pixel (x, y) background model, otherwise does not upgrade;
In the time carrying out background model renewal, generate the random integers i between 0~N, and replace i sample v in current background model with new samples v (x, y) i;
Step 4, for the new samples that is judged to be background model, upgrades the background model sample of pixel in neighborhood;
For the new samples v (x, y) that is judged to be background model, random decimal θ between generation 0~1, if θ is greater than threshold value T, is communicated with pixel background model in neighborhoods to 8 of pixel (x, y) and upgrades, otherwise do not upgrade;
When carrying out in neighborhood pixel background model while upgrading, select at random the pixel coordinate (x in 8 connection neighborhoods nG, y nG), generate the random integers i between 0~N, with new samples v (x, y) replacement pixel (x nG, y nG) background model in i sample v i.
CN201410017422.XA 2014-01-15 2014-01-15 Background model real-time updating method for non-coherent radar image Pending CN103778629A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410017422.XA CN103778629A (en) 2014-01-15 2014-01-15 Background model real-time updating method for non-coherent radar image

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410017422.XA CN103778629A (en) 2014-01-15 2014-01-15 Background model real-time updating method for non-coherent radar image

Publications (1)

Publication Number Publication Date
CN103778629A true CN103778629A (en) 2014-05-07

Family

ID=50570826

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410017422.XA Pending CN103778629A (en) 2014-01-15 2014-01-15 Background model real-time updating method for non-coherent radar image

Country Status (1)

Country Link
CN (1) CN103778629A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105184814A (en) * 2015-07-27 2015-12-23 成都天奥信息科技有限公司 Moving target detecting and tracking method based on multi-frame radar image
CN106023259A (en) * 2016-05-26 2016-10-12 史方 Method and device for detecting moving target frequency
CN108491796A (en) * 2018-03-22 2018-09-04 电子科技大学 A kind of time domain period point target detecting method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102314691A (en) * 2011-06-30 2012-01-11 北京平安视讯科技有限公司 Background model based on multiple information integration
CN102629383A (en) * 2012-02-28 2012-08-08 湖南大学 Motion object detection method based on random strategy
CN102665068A (en) * 2012-04-26 2012-09-12 中南林业科技大学 Panoramic type moving object surveillance method based on random update strategies

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102314691A (en) * 2011-06-30 2012-01-11 北京平安视讯科技有限公司 Background model based on multiple information integration
CN102629383A (en) * 2012-02-28 2012-08-08 湖南大学 Motion object detection method based on random strategy
CN102665068A (en) * 2012-04-26 2012-09-12 中南林业科技大学 Panoramic type moving object surveillance method based on random update strategies

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
胡雄鸽等: "使用随机策略进行运动目标检测方法研究", 《计算机工程与应用》 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105184814A (en) * 2015-07-27 2015-12-23 成都天奥信息科技有限公司 Moving target detecting and tracking method based on multi-frame radar image
CN106023259A (en) * 2016-05-26 2016-10-12 史方 Method and device for detecting moving target frequency
CN106023259B (en) * 2016-05-26 2018-12-07 史方 A kind of moving target frequency detecting method and device
CN108491796A (en) * 2018-03-22 2018-09-04 电子科技大学 A kind of time domain period point target detecting method
CN108491796B (en) * 2018-03-22 2021-10-22 电子科技大学 Time domain periodic point target detection method

Similar Documents

Publication Publication Date Title
CN109919002B (en) Yellow stop line identification method and device, computer equipment and storage medium
CN107358258B (en) SAR image target classification based on NSCT double CNN channels and selective attention mechanism
CN103136766B (en) A kind of object conspicuousness detection method based on color contrast and color distribution
CN104463795B (en) A kind of dot matrix DM image in 2 D code processing method and processing device
CN102096821A (en) Number plate identification method under strong interference environment on basis of complex network theory
CN103268481A (en) Method for extracting text in complex background image
CN104899839A (en) Ghost quick-inhibition method based on ViBe algorithm
CN105868734A (en) Power transmission line large-scale construction vehicle recognition method based on BOW image representation model
Li et al. A lane marking detection and tracking algorithm based on sub-regions
CN104766344A (en) Vehicle detecting method based on moving edge extractor
CN106446921A (en) High-voltage power transmission line barrier identification method and apparatus
CN116311000A (en) Firework detection method, device, equipment and storage medium
CN110310263B (en) SAR image residential area detection method based on significance analysis and background prior
CN103778629A (en) Background model real-time updating method for non-coherent radar image
CN105354547A (en) Pedestrian detection method in combination of texture and color features
CN108010050B (en) Foreground detection method based on adaptive background updating and selective background updating
CN104537632A (en) Infrared image histogram enhancing method based on edge extraction
CN113393430A (en) Thermal imaging image enhancement training method and device for fan blade defect detection
Shi et al. Image enhancement for degraded binary document images
CN105205833A (en) Moving object detection method and device based on space-time background model
CN103093241B (en) Based on the remote sensing image nonuniformity cloud layer method of discrimination of homogeneity process
CN103034864A (en) Video banner identification method based on color threshold and corner detection
CN106339709A (en) Real-time image extraction method
CN102842025B (en) The detection scene determination methods of video image and device
CN110188601B (en) Airport remote sensing image detection method based on learning

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20140507

RJ01 Rejection of invention patent application after publication