CN-121392564-B - Lake automatic extraction and analysis system based on GIS

CN121392564BCN 121392564 BCN121392564 BCN 121392564BCN-121392564-B

Abstract

The invention provides a lake automatic extraction and analysis system based on GIS, which relates to the technical field of remote sensing image processing and water body recognition. The system supports batch processing of water body and river vector data, automatically eliminates river interference, screens lakes by combining various geometric features, removes pseudo water bodies by using a multi-stage buffer area, compares the pseudo water bodies with standard lake data, calculates area differences, generates a first evaluation index, automatically compares the first evaluation index with the standard data, outputs precision indexes and visual results, generates a comprehensive evaluation index according to F1 scores, sets grades, marks the states of the lakes on an interface, adapts to resolution of the interface and supports highlight interaction, and can remarkably improve automation and intelligent levels of extraction and analysis of the lake water bodies.

Inventors

YU RUIHONG
LIU XIAOMIN
MA HONGLI
LI XIANGWEI
YE BOWEN
YAN SHU
LI JIAJUN
QU SHEN
LUO JIAN
SUN HEYANG
LIU ZEYUAN
YANG XU
MIAO PING
YAO JIPING

Assignees

内蒙古大学
内蒙古农业大学
鄂尔多斯市河湖保护中心

Dates

Publication Date: 20260508
Application Date: 20250829

Claims (6)

1. A lake automatic extraction and analysis system based on GIS is characterized by comprising the following specific steps: the data acquisition module is used for acquiring standard lake vector data, river vector data of an area to be analyzed and water vector data of each water area; The river interference removing module is used for identifying and removing the water body intersected with the river vector based on a spatial superposition analysis technology in the GIS, analyzing geometric characteristic parameter indexes of the water body based on a water body abnormality threshold value, removing the water body with an abnormal shape, and obtaining a non-intersected water body, wherein the related geometric characteristic parameter indexes of the water body comprise the length-width ratio and the roundness of the water body; The lake extraction module is used for removing the pseudo water body in the non-crossed water body through the multi-level buffer area to obtain a standard water body and extracting the lake where the standard water body is and vector data of the lake; The extraction evaluation module is used for calculating the area difference between the lake in which the standard water body is positioned and the standard lake to be used as a first evaluation index of the lake in which the standard water body is positioned, carrying out space superposition analysis on vector data of the lake in which the standard water body is positioned and the standard lake by using GIS software, obtaining a real sample, a false positive sample and a false negative sample of the lake in which the standard water body is positioned to calculate the precision and the recall rate of the real sample, and further calculating the F1 score to be used as a second evaluation index of the lake in which the standard water body is positioned; And the extraction effect grading module generates a lake comprehensive evaluation index based on the first evaluation index and the second evaluation index, and determines the lake extraction effect grade based on the lake comprehensive evaluation index.
2. The automatic extraction and analysis system for a GIS-based lake of claim 1, wherein the method for identifying and removing the water body intersecting the river vector and further removing the water body of abnormal shape is based on: Establishing a plane rectangular coordinate system based on a spatial superposition analysis technology in a GIS (geographic information system), importing vector data of a water body and a river under the same plane rectangular coordinate system, setting a plurality of measurement points in each water body area, ensuring that the measurement points can fully cover the whole water body area, calling a wing space analysis function to detect whether each measurement point is on a geometric characteristic line of the river one by one, recording measurement points intersected with the river, analyzing the water body corresponding to the points, judging that the water body corresponding to the measurement point is intersected with the river if a certain measurement point is intersected with the river line, removing the water body intersected with the river according to the intersected measurement points, and acquiring relevant geometric characteristic parameter indexes of the rest water body area after removing the water body intersected with the river according to the following formula: ; ; Wherein, the The roundness of the water body is represented, Representing the aspect ratio of the body of water, Is the circumference of the water body, Is the maximum length of the water body, Is the maximum width of the water body, Is the area of the water body; Setting a water body abnormality threshold, and comparing the related geometric characteristic parameter index of the water body with a preset threshold, wherein the water body abnormality threshold comprises a roundness threshold And aspect ratio threshold After the water body intersected with the river is removed, the rest water body area exists And is also provided with And removing the water body area to obtain the non-crossed water body.
3. The automatic extraction and analysis system for a GIS-based lake of claim 2, wherein the multi-stage buffer area is configured to remove pseudo-bodies of water in non-intersecting bodies of water to obtain standard bodies of water according to the following method: In GIS software, selecting non-intersecting water, calling a buffer zone tool, setting three-level buffer zones, and sequentially setting the buffer radius as 、、 Inputting a plurality of buffer area distances, generating a corresponding buffer area image layer, superposing all buffer areas together by using GIS software, carrying out morphological feature analysis on each non-crossing water area in each buffer area, evaluating the similarity between non-crossing water areas in the same radius buffer area by using shape indexes, and carrying out isolation detection to identify the water areas isolated in space according to the following formula: ; Wherein, the A shape index representing a body of non-intersecting water; Detecting each non-intersecting water body region in each buffer region as a target water body region, calculating a similarity index between the shape indexes of the target water body region and each remaining non-intersecting water body region in the same buffer region, measuring the similarity between the shape indexes of the water body regions by using Euclidean distance, and judging whether the target water body region is a pseudo water body or not by combining a preset distance threshold value according to the following formula: ; Wherein, the Representing a similarity index between the shape indices of two water regions, 、 Respectively represent the first Target water body area and the first The shape index of the remaining non-intersecting body of water region, For the index of the target water body region, Index for remaining non-intersecting water regions; Sequencing all similarity indexes in the same buffer area from small to large, selecting a minimum value of the similarity indexes, and extracting the geometric center distance between the corresponding target water body area and the non-intersecting water body area based on the minimum value of the similarity indexes And is at a distance from a preset threshold value Comparing, if The target water body region as the object of the isolation detection is regarded as an isolated water body, i.e., a pseudo water body, and is rejected.
4. The automatic extraction and analysis system for a lake based on a GIS according to claim 3, wherein the area difference between the lake where the standard water body is located and the standard lake is obtained, and the area difference is used as a first evaluation index of the lake where the standard water body is located, according to the following formula: ; Wherein, the Is the area of the lake in which the standard water body is positioned, Is the area of a standard lake, Is the area difference between a standard water body and a standard lake; Taking the area difference between the standard water body and the standard lake as a first evaluation index of the lake in which the standard water body is positioned 。
5. The automatic extraction and analysis system for lakes based on GIS according to claim 4, wherein the spatial superposition analysis is performed on the vector data of the standard lakes to obtain the real sample, the false positive sample and the false negative sample of the lakes where the standard water body is located to calculate the precision, the recall rate and the F1 score according to the following method: Based on vector data of a lake in which a standard water body is positioned and vector data of the standard lake, performing spatial intersection operation on the vector data of the standard lake and vector data of the lake in which the standard water body is positioned by using an intersection tool in a GIS, and acquiring an overlapping area to obtain a real sample Subtracting the part overlapped with the standard lake data from the vector data of the lake in which the standard water body is positioned, wherein the rest part is a false positive sample Subtracting the part overlapped with the vector data of the lake in which the standard water body is positioned from the vector data of the standard lake, wherein the rest part is a false negative sample Based on the actual sample obtained False positive sample False negative sample Calculating the accuracy and recall rate of the lake in which the standard water body is located, wherein the formula is as follows: ; ; Wherein, the The accuracy of the lake in which the standard water body is positioned is represented, Representing the recall rate of the lake in which the standard water body is located; f1 fraction is calculated based on accuracy and recall rate of lakes where standard water bodies are located, and the formula is as follows: ; Wherein, the F1 fraction representing the lake in which the standard water body is located, and taking the F1 fraction as a second evaluation index of the lake in which the standard water body is located 。
6. The GIS-based lake automatic extraction and analysis system of claim 5, wherein the first and second evaluation indexes are used to generate a comprehensive evaluation index of the lake, and the class index is set to describe the state of the lake according to the following formula: ; Wherein, the Representing comprehensive evaluation indexes of lakes; Setting the level standard of comprehensive evaluation index, setting several lake level index intervals according to lake data distribution condition, when the lake extraction analysis result is excellent, the level index intervals are When the lake extraction analysis result is good, the grade index interval is When the lake extraction analysis result is poor, the grade index interval is ; In a man-machine interaction interface, providing a file selection button, enabling a user to select a water vector file, a river vector file and an evaluation standard file, displaying the position and the state of a lake by using a graphical interface, using different colors or marks on icons or boundaries of the lake to represent different states, providing the button for the user to view analysis results, including comprehensive evaluation indexes and corresponding grades, regenerating an output folder, storing a report and a graph of the analysis results, and finally performing color coding on the lake according to the value of the comprehensive evaluation indexes to correspond to the grade standard of the lake.

Description

Lake automatic extraction and analysis system based on GIS Technical Field The invention relates to the technical field of remote sensing image processing and water body recognition, in particular to a lake automatic extraction and analysis system based on GIS. Background With the rapid development of remote sensing technology and GIS, lake automatic extraction and analysis systems gradually become important tools for water resource management and environment monitoring, the systems realize automatic identification, boundary extraction and area change analysis of lakes by utilizing high-resolution satellite images and advanced image processing algorithms, provide scientific basis for water environment protection and resource management, and how to effectively separate lake areas from the background is a challenge, the traditional image processing method can not cope with complex water body boundaries, especially the transition areas between water bodies and land and vegetation, and an effective strategy needs to be designed to eliminate the areas intersected with rivers or other small water bodies so as to avoid false extraction. In the prior art, the extraction of lake water bodies is dependent on manual interpretation or single file processing, and lacks an automatic, batched and intelligent processing tool, so that large-scale and multi-time phase lake identification and precision evaluation are difficult to efficiently complete, the automatic rejection capability of river interference is limited, and the real water bodies intersected with lakes and rivers are difficult to accurately distinguish, so that the accuracy of extraction results is influenced. It is therefore necessary to provide a GIS-based lake automatic extraction and analysis system to solve the problems. The above information disclosed in the background section is only for enhancement of understanding of the background of the disclosure and therefore it may include information that does not form the prior art that is already known to a person of ordinary skill in the art. Disclosure of Invention The invention aims to provide a GIS-based lake automatic extraction and analysis system for solving the problems in the background technology. In order to achieve the above purpose, the present invention provides the following technical solutions: a lake automatic extraction and analysis system based on GIS comprises the following specific steps: the data acquisition module is used for acquiring standard lake vector data, river vector data of an area to be analyzed and water vector data of each water area; The river interference removing module is used for identifying and removing the water body intersected with the river vector based on a spatial superposition analysis technology in the GIS, analyzing geometric characteristic parameter indexes of the water body based on a water body abnormality threshold value, removing the water body with an abnormal shape, and obtaining a non-intersected water body, wherein the related geometric characteristic parameter indexes of the water body comprise the length-width ratio and the roundness of the water body; The lake extraction module is used for removing the pseudo water body in the non-crossed water body through the multi-level buffer area to obtain a standard water body and extracting the lake where the standard water body is and vector data of the lake; The extraction evaluation module is used for calculating the area difference between the lake in which the standard water body is positioned and the standard lake to be used as a first evaluation index of the lake in which the standard water body is positioned, carrying out space superposition analysis on vector data of the lake in which the standard water body is positioned and the standard lake by using GIS software, obtaining a real sample, a false positive sample and a false negative sample of the lake in which the standard water body is positioned to calculate the precision and the recall rate of the real sample, and further calculating the F1 score to be used as a second evaluation index of the lake in which the standard water body is positioned; And the extraction effect grading module generates a lake comprehensive evaluation index based on the first evaluation index and the second evaluation index, and determines the lake extraction effect grade based on the lake comprehensive evaluation index. Further, identifying and rejecting the water body intersected with the river vector, and further removing the water body with the abnormal shape, wherein the method comprises the following steps: Establishing a plane rectangular coordinate system based on a spatial superposition analysis technology in a GIS (geographic information system), importing vector data of a water body and a river under the same plane rectangular coordinate system, setting a plurality of measurement points in each water body area, ensuring that the measurement points can fully cov