CN108629754A - ISAR image self-adaptive detail enhancement method - Google Patents

ISAR image self-adaptive detail enhancement method Download PDF

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CN108629754A
CN108629754A CN201810414603.4A CN201810414603A CN108629754A CN 108629754 A CN108629754 A CN 108629754A CN 201810414603 A CN201810414603 A CN 201810414603A CN 108629754 A CN108629754 A CN 108629754A
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amplitude
amplitude level
level
series
isar
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CN108629754B (en
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田彪
刘永祥
黎湘
霍凯
姜卫东
卢哲俊
张双辉
张新禹
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National University of Defense Technology
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    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T5/00Image enhancement or restoration
    • G06T5/40Image enhancement or restoration using histogram techniques
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T5/00Image enhancement or restoration
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T5/00Image enhancement or restoration
    • G06T5/90Dynamic range modification of images or parts thereof
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00Indexing scheme for image analysis or image enhancement
    • G06T2207/10Image acquisition modality
    • G06T2207/10032Satellite or aerial image; Remote sensing
    • G06T2207/10044Radar image
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00Indexing scheme for image analysis or image enhancement
    • G06T2207/20Special algorithmic details
    • G06T2207/20004Adaptive image processing
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00Indexing scheme for image analysis or image enhancement
    • G06T2207/20Special algorithmic details
    • G06T2207/20172Image enhancement details

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  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Image Processing (AREA)
  • Facsimile Image Signal Circuits (AREA)

Abstract

The invention provides an ISAR image self-adaptive detail enhancement method which comprises the following steps of S1 obtaining L-level gray level histogram of an ISAR image, S2 compressing empty amplitude levels, S3 judging conditions, S4 compressing low-probability amplitude levels, S5 expanding high-probability amplitude levels, and S6 mapping gray level.

Description

A kind of ISAR image adaptives detail enhancing method
Technical field
At ISAR (Inverse Synthetic Aperture Radar, Inverse Synthetic Aperture Radar) image Reason technology more particularly to a kind of ISAR image adaptive details based on the compression of redundancy amplitude level and the extension of high probability amplitude level increase Strong method.
Background technology
It is different from optical imagery, ISAR images in imaging process by target property, radar system, ambient noise and at As the influence of many factors such as algorithm, it is usually expressed as isolated scattering center distribution, has sparsity, dynamic range big, right The features such as more relatively low than degree.This makes subsequent image analysis, interpretation face prodigious difficulty, therefore before subsequent processing, Details enhancing processing is carried out to ISAR images to seem very necessary.
Existing image detail enhancement method is mainly used in optical imagery.Such as Gamma bearing calibrations, referring to document (Peng State's good fortune, the research and realization [J] Electronics Engineers that Gamma is corrected in the just great image procossings of woods, 2006, (2):30-32, 36.).This method improves picture contrast by a specific Gamma transformation operator.But this method is applied to tool When the ISAR image details for having sparsity, dynamic range big enhance, it is difficult to obtain satisfactory effect.Such as histogram equalization Method, referring to document, (marine sites Zhang Rui, Jia Na image enchancing method is summarized [J] liquid crystal and is shown, 2017, (10):828-834.), Then increase dynamic range of images by making the probability density function of image gray levels meet the form of approaches uniformity distribution and carries Hi-vision contrast, for dynamic range prodigious ISAR images, it is difficult to realize that details enhances, and to target subject Enhancing can even weaken the visuality of image.Currently, not yet finding the related data in relation to ISAR image detail enhancement methods.
Invention content
In view of the above technology the problem of, the present invention propose a kind of based on the compression of redundancy amplitude level and high probability amplitude The ISAR image adaptive detail enhancing methods of grade extension.This method utilizes the sparsity of ISAR images, to ISAR gray level images Redundancy amplitude level is compressed, and is extended to high probability amplitude level, is realized the enhancing of image adaptive details, be can effectively improve The visual effect of target ISAR images enriches target detail information.
The technical solution adopted by the present invention is:A kind of ISAR based on the compression of redundancy amplitude level and the extension of high probability amplitude level Image adaptive detail enhancing method, this approach includes the following steps:
If the ISAR images G obtained the gray value g (m, n), wherein m ∈ [1, M], n ∈ [1, N] at coordinate (m, n), M Indicated respectively with N ISAR images G orientation and distance to resolution cell number.
S1:Seek the L grade grey level histograms of ISAR images
It is L grades that the tonal range of ISAR images G, which is evenly dividing, obtains the corresponding L grades of grey level histogram of ISAR images G. The value of amplitude series L is determined according to the tonal range size of ISAR images.
S2:Empty amplitude level compression
The amplitude level for being 0 comprising number of pixels in L grades of grey level histograms is deleted, the L ' grade gray scales that amplitude series is L ' are obtained Histogram.
S3:Condition judgment
If L ' is less than the final series L of setting0, then S5 is executed;If L ' is more than the final series L of setting0, then execute S4;Otherwise, S6 is executed.Final series L0The number of greyscale levels that quantifies as needed of value determine, generally take L0=256.
S4:Low probability amplitude level is compressed
Amplitude level minimum to the frequency of occurrences S4.1 carries out compression processing, i.e., by the amplitude level frequency of occurrences adjacent thereto Lower amplitude level merges.
The new corresponding amplitude level grey level histogram of amplitude sum of series after S4.2 statistics compression processings, if new amplitude series Equal to the final series L of setting0, then S6 is executed;Otherwise, S4.1 is executed.
S5:High probability amplitude level extends
S5.1 is extended processing to the highest amplitude level of the frequency of occurrences, i.e., the corresponding gray scale interval of the amplitude level is uniform Division obtains two new amplitude levels.
New amplitude level grey level histogram after S5.2 statistics extension process, if new amplitude series is equal to the final level of setting Number L0, then S6 is executed;Otherwise, S5.1 is executed.
S6:Grey scale mapping
L0The corresponding ISAR images G ' of grade grey level histogram, as enhanced result.
Beneficial effects of the present invention:Method processing through the invention is big for extraterrestrial target ISAR dynamic range of images And the characteristics of high-amplitude area is sparse, histogram redundancy, adaptively carries out the compression of redundancy amplitude level and high probability amplitude level expands Exhibition effectively improves the local contrast of target gray image in the case where retaining target detail information and not losing, improves target The visual effect of ISAR images promotes target identification ability, has important engineering application value.
Description of the drawings
Fig. 1 is process flow of the present invention;
Fig. 2 is the grey level histogram for carrying out emulation experiment acquisition;
Fig. 3 is the result for carrying out contrast experiment.
Specific implementation mode
The specific implementation mode of the present invention is described further below in conjunction with the accompanying drawings.
Fig. 1 is process flow of the present invention.Fig. 2 is that the present invention is based on the compressions of redundancy amplitude level and the extension of high probability amplitude level Image enhancement schematic diagram.
A kind of ISAR image adaptives based on the compression of redundancy amplitude level and the extension of high probability amplitude level of the present invention are thin Enhancement Method is saved, this approach includes the following steps:
S1:Seek the L grade grey level histograms of ISAR images.
It is L grades that the tonal range of ISAR images G, which is evenly dividing, obtains the corresponding L grades of grey level histogram of ISAR images G. The value of amplitude series L is determined according to the amplitude range size of ISAR images.Wherein, it is evenly dividing and is meant that so that gray scale is straight The length in the corresponding tonal range section of each amplitude level of square figure is consistent.
S2:Empty amplitude level compression
The amplitude level for being 0 comprising number of pixels in L grades of grey level histograms is deleted, the intensity histogram that amplitude series is L ' is obtained Figure.
S3:Condition judgment
By condition judgment, decision is to carry out the compression of low probability amplitude level and the extension of high probability amplitude level, or terminate skill Art scheme.
S4:Low probability amplitude level is compressed
If carrying out amplitude level compression, the amplitude level minimum to the frequency of occurrences carries out compression processing, and the frequency of occurrences is minimum Amplitude level refer to the amplitude level (i.e. gray scale interval) include the minimum amplitude level of number of pixels.The amplitude level is adjacent thereto The lower amplitude level of the frequency of occurrences merges, and refers to from two (or 1) amplitude levels adjacent in gray scale interval with the amplitude level In, selection is merged comprising the less amplitude level of pixel.The gray scale interval that new amplitude level includes is two width being merged Spend the sum of the gray scale interval of grade.
S5:High probability amplitude level extends
Processing is extended to the highest amplitude level of the frequency of occurrences, i.e., is carried out the corresponding gray scale interval of the amplitude level uniform Division obtains two new gray scale intervals, and each gray scale interval corresponds to a new amplitude level.Statistics falls into new amplitude level Pixel number, to obtain new amplitude level grey level histogram.
S6:Grey scale mapping
Fig. 2 is the grey level histogram for carrying out emulation experiment acquisition.Fig. 2-(a) is that the ISAR images that use are corresponding in experiment Original grey level histogram, amplitude series L=1024.When forming grey level histogram, 1024 are divided by Imhist functions A rank.Fig. 2-(b) is using the present invention is based on the gray scale obtained after the compression of redundancy amplitude level and the extension of high probability amplitude level is straight Fang Tu;Amplitude series includes L at this time0=256 ranks.It can be seen from the figure that by using the present invention, histogram is removing It is expanded after redundancy, the local contrast of target gray image is effectively improved in the case where retaining target detail information and not losing Degree.
Fig. 3 is the result for carrying out contrast experiment.(a) it is the original I SAR imaging results for emulating Aircraft Targets, is (b) to utilize Gamma transformation (coefficient is 0.4) enhancing is as a result, (c) be the enhancing of existing histogram equalization as a result, (d) being to utilize the present invention The image enhancement result that method obtains.It can be seen from the figure that Gamma converter techniques are to big with sparsity, dynamic range When ISAR image enhancements, target and background noise is carried out at the same time enhancing.Histogram equalization method is very big for dynamic range ISAR images for, it is difficult to realize details enhance, and to the enhancing of target subject even can thicken.And the side of the present invention Method can more effectively enhance detailed information.
Further to verify effectiveness of the invention, System of Comprehensive Evaluation is built using three modules, is carried out Quantitative analysis, including index of fuzziness, local contrast, details area variance.Index of fuzziness is smaller, local contrast is got over Greatly, details area variance is bigger, and image enhancement performance is more superior.It is quantitative to the experimental result of Fig. 3 using above three index Comparison, as shown in table 1.
1 quantitative comparison of table
It is as follows that comparing result is obtained according to table 1:
1. according to the comparing result of index of fuzziness and local contrast it is found that the method for the present invention is improving image detail letter It is more excellent than other algorithms in terms of the abundant degree and local contrast of breath.
2. in terms of details area variance yields, the result of the method for the present invention is equally maximum, and increasing degree is larger.This result Show the method for the present invention when realizing Larger Dynamic Ratage Coutpressioit, retain local detail or keeps the ability of local contrast than other Method is more superior.
Emulation and contrast experiment are realized by Matlab2010a.Operating system is Microsoft Windows XP ProfessionalSP3, processor are Pentium Dual-Core 2.7GHz.The measured data that Fig. 3 emulation experiments utilize is big Small is 401 × 256, time overhead comparing result used, as shown in the table.
The time overhead (s) of 2. algorithms of different of table
Algorithm Gama is converted Conventional histogram converts This patent method
Time overhead (mean value) 0.027 0.025 0.2
The comparing result provided from table can see, and the method for the present invention emulation hour operation quantity has certain increasing than other algorithms It is long, but the increase of this time overhead can be ignored relative to the promotion of algorithm performance.

Claims (1)

1. a kind of ISAR image adaptives detail enhancing method, ISAR refer to Inverse Synthetic Aperture Radar, if the ISAR images G obtained Gray value g (m, n) at coordinate (m, n), wherein m ∈ [1, M], n ∈ [1, N], M and N indicate ISAR images G in orientation respectively To with distance to resolution cell number, which is characterized in that include the following steps:
S1:Seek the L grade grey level histograms of ISAR images:
It is L grades that the tonal range of ISAR images G, which is evenly dividing, obtains the corresponding L grades of grey level histogram of ISAR images G;Amplitude The value of series L is determined according to the tonal range size of ISAR images;
S2:Empty amplitude level compression:
The amplitude level for being 0 comprising number of pixels in L grades of grey level histograms is deleted, the L ' grade intensity histograms that amplitude series is L ' are obtained Figure;
S3:Condition judgment:
If L ' is less than the final series L of setting0, then S5 is executed;If L ' is more than the final series L of setting0, then S4 is executed;It is no Then, S6 is executed;Final series L0The number of greyscale levels that quantifies as needed of value determine;
S4:Low probability amplitude level is compressed:
Amplitude level minimum to the frequency of occurrences S4.1 carries out compression processing, i.e., the amplitude level frequency of occurrences adjacent thereto is relatively low Amplitude level merge;
The new corresponding amplitude level grey level histogram of amplitude sum of series after S4.2 statistics compression processings, if new amplitude series is equal to The final series L of setting0, then S6 is executed;Otherwise, S4.1 is executed;
S5:High probability amplitude level extends:
S5.1 is extended processing to the highest amplitude level of the frequency of occurrences, i.e., is evenly dividing the corresponding gray scale interval of the amplitude level Obtain two new amplitude levels;
New amplitude level grey level histogram after S5.2 statistics extension process, if new amplitude series is equal to the final series L of setting0, Then execute S6;Otherwise, S5.1 is executed;
S6:Grey scale mapping:
L0The corresponding ISAR images G ' of grade grey level histogram, as enhanced result.
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Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102129675A (en) * 2011-02-24 2011-07-20 中国兵器工业系统总体部 Nonlinear adaptive infrared image enhancing method
CN102169580A (en) * 2011-04-08 2011-08-31 中国船舶重工集团公司第七○二研究所 Self-adaptive image processing method utilizing image statistic characteristics
CN106342330B (en) * 2009-08-12 2013-04-17 中国航空工业集团公司洛阳电光设备研究所 A kind of image enchancing method of the gamma correction based on infrared image
CN105069460A (en) * 2015-08-21 2015-11-18 航天长征火箭技术有限公司 ISAR image ship target feature extraction method
CN105184759A (en) * 2015-09-22 2015-12-23 中国科学院西安光学精密机械研究所 Image self-adaptive enhancement method based on histogram compactness transformation
CN106296599A (en) * 2016-07-29 2017-01-04 南京信息工程大学 A kind of method for adaptive image enhancement
CN106339994A (en) * 2016-08-29 2017-01-18 合肥康胜达智能科技有限公司 Image enhancement method
CN107292834A (en) * 2017-05-24 2017-10-24 杭州天铂红外光电技术有限公司 Infrared image detail enhancing method
CN107527333A (en) * 2017-07-31 2017-12-29 湖北工业大学 A kind of rapid image Enhancement Method based on gamma transformation
CN107945122A (en) * 2017-11-07 2018-04-20 武汉大学 Infrared image enhancing method and system based on self-adapting histogram segmentation

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106342330B (en) * 2009-08-12 2013-04-17 中国航空工业集团公司洛阳电光设备研究所 A kind of image enchancing method of the gamma correction based on infrared image
CN102129675A (en) * 2011-02-24 2011-07-20 中国兵器工业系统总体部 Nonlinear adaptive infrared image enhancing method
CN102169580A (en) * 2011-04-08 2011-08-31 中国船舶重工集团公司第七○二研究所 Self-adaptive image processing method utilizing image statistic characteristics
CN105069460A (en) * 2015-08-21 2015-11-18 航天长征火箭技术有限公司 ISAR image ship target feature extraction method
CN105184759A (en) * 2015-09-22 2015-12-23 中国科学院西安光学精密机械研究所 Image self-adaptive enhancement method based on histogram compactness transformation
CN106296599A (en) * 2016-07-29 2017-01-04 南京信息工程大学 A kind of method for adaptive image enhancement
CN106339994A (en) * 2016-08-29 2017-01-18 合肥康胜达智能科技有限公司 Image enhancement method
CN107292834A (en) * 2017-05-24 2017-10-24 杭州天铂红外光电技术有限公司 Infrared image detail enhancing method
CN107527333A (en) * 2017-07-31 2017-12-29 湖北工业大学 A kind of rapid image Enhancement Method based on gamma transformation
CN107945122A (en) * 2017-11-07 2018-04-20 武汉大学 Infrared image enhancing method and system based on self-adapting histogram segmentation

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
NING LIU等: "Detail enhancement for high-dynamic-range infrared images based on guided image filter", 《INFRARED PHYSICS & TECHNOLOGY》 *
刘慧敏等: "逆合成孔径雷达像轮廓提取方法", 《系统工程与电子技术》 *
张颖宁: "多基站ISAR成像融合算法研究", 《中国优秀硕士学位论文全文数据库 信息科技辑》 *
杨效余等: "舰船ISAR图像特征提取方法研究", 《遥测遥控》 *
田淑芳,詹骞主编: "《遥感地质学(第2版)》", 31 January 2014, 地质出版社 *
蔡骏: "红外图像自适应细节增强算法的研究与实现", 《中国优秀硕士学位论文全文数据库 信息科技辑》 *

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