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CN108182675B - Surface element shielding judgment method during irradiation of random fluctuation interface by sound wave - Google Patents

Surface element shielding judgment method during irradiation of random fluctuation interface by sound wave Download PDF

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CN108182675B
CN108182675B CN201711372631.6A CN201711372631A CN108182675B CN 108182675 B CN108182675 B CN 108182675B CN 201711372631 A CN201711372631 A CN 201711372631A CN 108182675 B CN108182675 B CN 108182675B
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occlusion
panel
sound wave
surface element
judging
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CN108182675A (en
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陈文剑
殷敬伟
厉夫兵
于洋
郭龙祥
赵罡
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Harbin Engineering University
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    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/0002—Inspection of images, e.g. flaw detection
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
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    • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
    • G—PHYSICS
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    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
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Abstract

本发明提供的是一种声波照射随机起伏界面时的面元遮挡判断方法。包括将随机起伏界面投影到观测平面，并得到观测平面边长分别为Lx和Ly；设置观测平面像素分辨率Npix；利用Z‑buffer算法以像素为单位将各个面元离散化，计算得到每个面元的遮挡率QM；设置面元遮挡判断阈值Q，根据遮挡率QM和阈值Q的大小关系进行面元遮挡判断。本发明通过计算面元遮挡率判断面元是否被遮挡，避免了进行面元搜索判断的过程，减小了计算量。

Figure 201711372631

The invention provides a method for judging panel occlusion when a sound wave illuminates a randomly undulating interface. Including projecting the random undulating interface onto the observation plane, and obtaining the side lengths of the observation plane as L x and L y respectively; setting the pixel resolution of the observation plane N pix ; using the Z-buffer algorithm to discretize each surface element in pixel units, calculate Obtain the occlusion rate Q M of each panel; set the panel occlusion judgment threshold Q, and perform panel occlusion judgment according to the size relationship between the occlusion rate Q M and the threshold Q. The invention judges whether the surfel is blocked by calculating the occlusion rate of the surfel, which avoids the process of searching and judging the surfel and reduces the calculation amount.

Figure 201711372631

Description

Surface element shielding judgment method during irradiation of random fluctuation interface by sound wave
Technical Field
The invention relates to an underwater target detection method, in particular to a method for judging the shielding of a surface element which is not irradiated by sound waves.
Background
The method is characterized in that the occlusion judgment of the surface element is one of key technologies when a physical acoustic method is used for calculating the problem of a random fluctuating interface scattering sound field, and the surface element which does not contribute to the scattering sound field is removed by judging the occlusion relation of the surface element. The traditional method is to perform traversal search and judge whether each surface element is mutually shielded, so that the problems of large calculation amount and low efficiency exist. The fast search method of the occlusion surface element is researched by methods such as a topological trace method (research on occlusion algorithm of complex cavities of airplane engines in the Tantao, Chenyulin, 2013, volume 11, No. 2) and a surface element grouping method (Jijin ancestor, Liu station combination, electromagnetic occlusion algorithm based on surface element grouping and optimization thereof, the university of Beijing aerospace, 2009, volume 35, No. 4), but the occlusion problem of regular-shaped targets is solved. In the method for rapidly searching occlusion surface elements when random fluctuation interfaces are irradiated by sound waves (CN2015101409180), the calculation amount is reduced by a method for reducing the search area, the efficiency is improved relative to the traversal search, and the surface element search still needs to be carried out.
Disclosure of Invention
The invention aims to provide a surface element shielding judgment method when sound waves with simple logic and small calculation amount irradiate a random fluctuation interface.
The purpose of the invention is realized as follows:
(1) importing N surface element node information of a random fluctuating interface subjected to triangular surface element division and a sound wave incidence direction;
(2) projecting the random fluctuating interface to an observation plane according to the incident direction of sound waves, wherein the side lengths of the observation plane are LxAnd Ly；
(3) Setting the pixel resolution N of the observation planepixLet N stand forpix≥2LmaxL, wherein LmaxIs LxAnd LyL is the bin side length;
(4) discretizing each surface element by using a Z-buffer algorithm and taking pixels as units, and recording the pixel number M of the non-shielding display on each surface element0And calculating to obtain the pixel number M of each bin for normal display1Memory for recording
Figure BDA0001514036680000011
The surface element shielding rate is;
(5) setting a surface element shielding judgment threshold value Q, if QMIf the surface element is larger than Q, judging that the surface element is not blocked; otherwise, the image is judged to be blocked.
(6) And 5, judging all surface elements in the step 5, and deleting all blocked surface elements, namely finishing the surface element blocking judgment in the sound wave irradiation process.
The present invention may further comprise:
1. the observation plane completely contains the projection plane of the random undulating interface.
2. The value range of Q is (0, 1).
Aiming at the surface element shielding problem of a random fluctuation interface, the invention provides a method for judging the shielding surface element when sound waves irradiate the random fluctuation interface by calculating the surface element shielding rate without surface element searching, so that the process of searching and judging the surface element by the existing method is avoided, and compared with the existing method for judging the shielding by searching, the method has the following advantages that:
1. the Z-buffer algorithm is utilized to calculate the pixel number on the surface element only, and the surface element is subjected to shielding judgment by calculating the surface element shielding rate, so that the surface element searching and judging process is avoided, and the calculated amount is reduced;
2. the method has simple logic and is easy to realize the program.
Drawings
Fig. 1 is a random undulating interface that has been triangularly binned.
Fig. 2 shows the azimuth and elevation angles in a rectangular coordinate system.
Fig. 3 is a schematic projection view.
FIG. 4 is a random undulating interface with occluded bins removed.
FIG. 5 is a flow chart of bin occlusion when the acoustic wave illuminates the relief interface.
Detailed Description
With reference to fig. 5, the method for determining surface element shielding when a random fluctuation interface is irradiated by sound waves of the present invention includes the following steps:
1. and importing N surface element node information of the random undulating interface subjected to triangular surface element division and the incident direction of the sound wave.
2. Projecting the random fluctuation interface to an observation plane according to the incident sound wave direction, wherein the observation plane completely comprises the projection plane of the random fluctuation interface, and the side lengths of the observation plane are LxAnd Ly。
3. Setting an observation plane pixel resolution NpixLet N stand forpix≥2LmaxL, wherein LmaxIs LxAnd LyAnd l is the bin side length.
4. Using Z-buThe ffer algorithm discretizes each surface element by taking pixels as units, and records the pixel number M of the unshielded display on each surface element0And calculating to obtain the pixel number M of each bin for normal display1Memory for recording
Figure BDA0001514036680000021
Is the bin shading rate.
5. Setting a surface element shielding judgment threshold value Q, wherein the value range of Q is (0,1), and if Q isMIf the surface element is larger than Q, judging that the surface element is not blocked; otherwise, the image is judged to be blocked.
6. And 5, judging all surface elements in the step 5, and deleting all blocked surface elements, namely finishing the surface element blocking judgment in the sound wave irradiation process.
The invention is described in more detail below by way of example.
In the first step, referring to fig. 1, the lengths of the random undulating interface in the x direction and the y direction are both 6m, and the side length of the surface element is 0.1 m.
Secondly, referring to fig. 2, the azimuth angle θ of the incident direction of the sound wave is set to 0 degree, and the pitch angle is set
Figure BDA0001514036680000031
Thirdly, with reference to fig. 3, the random undulating interface 1 is projected to the observation plane 2 according to the incident sound wave direction, and the side lengths of the observation plane 2 are respectively Lx4.24m and Ly＝6m。
The fourth step, according to the formula Npix≥2LmaxSetting the pixel resolution N of an observation planepixWherein L ismax＝LyN is set in this embodiment as 6mpix＝512。
Fifthly, discretizing each surface element by using a Z-buffer algorithm and taking pixels as units, and recording the number M of pixels displayed without shielding on each surface element0And calculating to obtain the pixel number M of each bin for normal display1Memory for recording
Figure BDA0001514036680000032
For bin occlusion rate, preserving occlusion of all binsAnd (4) obtaining a rate result.
The sixth step is to set a bin blocking judgment threshold Q, where the value range of Q is (0,1), and Q is set to 0.5 in this embodiment.
And seventhly, comparing the shielding rate of all the surface elements stored in the fifth step with a shielding judgment threshold Q with the graph shown in FIG. 4, and deleting the surface elements with the shielding rate smaller than the threshold Q to finish the judgment of the shielding of the surface elements.

Claims (3)

1.一种声波照射随机起伏界面时的面元遮挡判断方法，其特征是：不需进行面元搜索，通过计算面元遮挡率对声波照射随机起伏界面时的遮挡面元进行判断的方法，避免了现有方法对面元进行搜索判断的过程；1. a method for judging panel occlusion when a sound wave irradiates a random undulating interface, characterized in that: it is not necessary to carry out a panel search, and the method for judging the occlusion panel when a sound wave irradiates a random undulating interface by calculating the panel occlusion rate, It avoids the process of searching and judging the face element in the existing method; (1)、导入已进行三角面元划分的随机起伏界面的N个面元节点信息和声波入射方向；(1) Import the node information and the sound wave incident direction of the N face elements of the random undulating interface that has been divided into triangular face elements; (2)、根据声波入射方向，将随机起伏界面投影到观测平面，观测平面边长分别为Lx和Ly；(2), according to the incident direction of the sound wave, project the random undulating interface to the observation plane, and the side lengths of the observation plane are L x and Ly respectively; (3)、设置观测平面像素分辨率Npix，令Npix≥2Lmax/l，其中Lmax是Lx和Ly中的最大值，l为面元边长；(3), set the pixel resolution N pix of the observation plane, so that N pix ≥ 2L max /l, where L max is the maximum value between L x and L y , and l is the edge length of the panel; (4)、利用Z-buffer算法以像素为单位将各个面元离散化，记录每个面元上无遮挡显示的像素数M0，并计算得到每个面元正常显示的像素数M1，记
Figure FDA0003350464170000011
为面元遮挡率；(4) Use the Z-buffer algorithm to discretize each surfel in units of pixels, record the number of pixels M 0 displayed without occlusion on each surfel, and calculate the number of pixels M 1 normally displayed on each surfel, remember
Figure FDA0003350464170000011
is the occlusion rate of the surfel; (5)、设置面元遮挡判断阈值Q，如果QM＞Q，则判断面元未被遮挡；反之，判断为被遮挡；(5), set the panel occlusion judgment threshold Q, if Q M > Q, then judge that the panel is not occluded; otherwise, it is judged to be occluded; (6)、对所有面元进行步骤5的判断，删除掉所有被遮挡的面元，即完成了声波照射时的面元遮挡判断。(6) Perform the judgment of step 5 on all the surfels, and delete all the occluded surfels, that is, the occlusion judgment of the surfels when the sound wave is irradiated is completed. 2.根据权利要求1所述的声波照射随机起伏界面时的面元遮挡判断方法，其特征是：所述观测平面完全包含随机起伏界面的投影面。2 . The method for judging panel occlusion when a sound wave illuminates a random undulating interface according to claim 1 , wherein the observation plane completely includes the projection surface of the random undulating interface. 3 . 3.根据权利要求1或2所述的声波照射随机起伏界面时的面元遮挡判断方法，其特征是：Q的取值范围为(0,1)。3 . The method for judging panel occlusion when a sound wave irradiates a random undulating interface according to claim 1 or 2 , wherein the value range of Q is (0, 1). 4 .
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6480205B1 (en) * 1998-07-22 2002-11-12 Nvidia Corporation Method and apparatus for occlusion culling in graphics systems
EP1439493A2 (en) * 2003-01-17 2004-07-21 Hybrid Graphics Oy Occlusion culling method
US7375727B1 (en) * 1998-07-22 2008-05-20 Nvidia Corporation System, method and computer program product for geometrically transforming geometric objects
CN102800058A (en) * 2012-07-06 2012-11-28 哈尔滨工程大学 Remote sensing image cloud removing method based on sparse representation
CN104765028A (en) * 2015-03-27 2015-07-08 哈尔滨工程大学 Gauss random fluctuation seabed interface reverberation signal simulation method
CN104992064A (en) * 2015-07-09 2015-10-21 西安电子科技大学 Partitioning parallel computing method for backward radar echoes of multi-scale electrically large-region rough sea surface
CN105701284A (en) * 2016-01-11 2016-06-22 西安电子科技大学 Parallel computing method for time-varying multi-scale electrically-large-area sea-surface electromagnetic scattering vector field

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040104935A1 (en) * 2001-01-26 2004-06-03 Todd Williamson Virtual reality immersion system
JP4142065B2 (en) * 2006-05-22 2008-08-27 株式会社ソニー・コンピュータエンタテインメント Reduced Z-buffer generation method, hidden surface removal method, and occlusion culling method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6480205B1 (en) * 1998-07-22 2002-11-12 Nvidia Corporation Method and apparatus for occlusion culling in graphics systems
US7375727B1 (en) * 1998-07-22 2008-05-20 Nvidia Corporation System, method and computer program product for geometrically transforming geometric objects
EP1439493A2 (en) * 2003-01-17 2004-07-21 Hybrid Graphics Oy Occlusion culling method
CN102800058A (en) * 2012-07-06 2012-11-28 哈尔滨工程大学 Remote sensing image cloud removing method based on sparse representation
CN104765028A (en) * 2015-03-27 2015-07-08 哈尔滨工程大学 Gauss random fluctuation seabed interface reverberation signal simulation method
CN104992064A (en) * 2015-07-09 2015-10-21 西安电子科技大学 Partitioning parallel computing method for backward radar echoes of multi-scale electrically large-region rough sea surface
CN105701284A (en) * 2016-01-11 2016-06-22 西安电子科技大学 Parallel computing method for time-varying multi-scale electrically-large-area sea-surface electromagnetic scattering vector field

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
融合SGM 与Z-Buffer 的真正射影像遮挡检测算法;化雪诚等;《桂林电子科技大学学报》;20170430;第37卷(第2期);第134-139页 *

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