Ocean region instantaneous water line extraction method and device based on optical remote sensing image

Abstract

The invention provides a method and a device for extracting an instantaneous waterline of an ocean region based on an optical remote sensing image. The method comprises the following steps: acquiring the optical remote sensing image of a target ocean region; performing ocean water body enhancement on the optical remote sensing image by calculating an ocean water body index of a pixel in the optical remote sensing image; and based on the ocean water body index of each pixel, determining an instantaneous water line of the target ocean area through an edge detection algorithm. According to the ocean area instantaneous water line extraction method and device based on the optical remote sensing image, the extracted instantaneous water line is complete and continuous, the accuracy of the instantaneous water line is greatly improved, and the automation degree and the processing efficiency of instantaneous water line extraction are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and in particular to a method and a device for extracting instantaneous water edge lines of an ocean area based on optical remote sensing images. Background Art

[0002] The extraction of instantaneous water edge is the premise and foundation for the study of coastline monitoring and coastline change. The traditional method of measuring instantaneous water edge is field measurement. Due to the characteristics of instantaneous water edge such as wide range, rapid change and easy fragmentation, the field measurement is labor-intensive, costly and time-consuming, and it is difficult to monitor the dynamic changes of instantaneous water edge.

[0003] Currently, there are instantaneous water edge extraction methods such as threshold method. For example, by analyzing the spectral characteristic curve of water body, selecting appropriate bands to build a model, and setting appropriate thresholds to separate water body and land. This method is simple and fast, but may be affected by factors such as lighting conditions and water body type. The instantaneous water edge extracted by the current instantaneous water edge extraction algorithm is discontinuous, incomplete, and has low accuracy, and the effect is very poor in practical applications. Summary of the invention

[0004] The present invention provides a method and device for extracting instantaneous water edge lines of ocean areas based on optical remote sensing images, so as to solve the defects of the instantaneous water edge lines extracted by the current instantaneous water edge line extraction algorithm in the prior art, that is, the instantaneous water edge lines extracted are discontinuous, incomplete and of low accuracy, and the instantaneous water edge lines extracted are complete, continuous and of high accuracy.

[0005] The present invention provides a method for extracting instantaneous water edge lines of ocean areas based on optical remote sensing images, comprising the following steps: acquiring an optical remote sensing image of a target ocean area; performing ocean water enhancement on the optical remote sensing image by calculating an ocean water index of a pixel in the optical remote sensing image; and determining an instantaneous water edge line of the target ocean area by an edge detection algorithm based on the ocean water index of each pixel.

[0006] According to a method for extracting instantaneous water edges in ocean areas based on optical remote sensing images provided by the present invention, the ocean water index is constructed based on the difference between a first brightness value and a second brightness value; wherein the first brightness value is the sum of a blue band brightness value and a green band brightness value, and the second brightness value is the sum of a red band brightness value and a near-infrared band brightness value.

[0007] According to a method for extracting instantaneous water edge lines in an ocean area based on optical remote sensing images provided by the present invention, the ocean water index is expressed as: in, represents the ocean water index, Indicates the brightness value of the blue band. Indicates the brightness value of the green band, Indicates the brightness value of the red band, Represents the brightness value of the near-infrared band.

[0008] According to a method for extracting instantaneous water edges of ocean areas based on optical remote sensing images provided by the present invention, before performing ocean water enhancement on the optical remote sensing images by calculating the ocean water index of pixels in the optical remote sensing images, the method further includes: performing image preprocessing on the optical remote sensing images; wherein the image preprocessing includes radiation calibration, atmospheric correction and orthorectification.

[0009] According to a method for extracting instantaneous water edges in ocean areas based on optical remote sensing images provided by the present invention, after the optical remote sensing images are preprocessed, the method further comprises: denoising the optical remote sensing images by minimum noise separation transformation.

[0010] According to a method for extracting the instantaneous water edge of an ocean area based on optical remote sensing images provided by the present invention, before determining the instantaneous water edge of the target ocean area through an edge detection algorithm, the method also includes: setting an initial evolution area of ​​the edge detection algorithm; wherein the initial evolution area is located near the sea-land boundary.

[0011] According to a method for extracting instantaneous water edges of ocean areas based on optical remote sensing images provided by the present invention, after determining the instantaneous water edges of the target ocean area by an edge detection algorithm, the method further includes: obtaining a sea-land segmentation result based on the instantaneous water edges; and binarizing the sea-land segmentation result.

[0012] According to a method for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images provided by the present invention, after binarizing the land-sea segmentation result, the method further comprises: vectorizing the land-sea segmentation result.

[0013] According to a method for extracting instantaneous waterside lines in an ocean area based on optical remote sensing images provided by the present invention, the land-sea segmentation result retains the geographic information of the optical remote sensing images.

[0014] The present invention also provides an instantaneous water edge extraction device for an ocean area based on optical remote sensing images, comprising the following modules: an acquisition module, used to acquire an optical remote sensing image of a target ocean area; an enhancement module, used to enhance the ocean water body of the optical remote sensing image by calculating the ocean water body index of the pixels in the optical remote sensing image; a determination module, used to determine the instantaneous water edge of the target ocean area through an edge detection algorithm based on the ocean water body index of each pixel.

[0015] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method for extracting instantaneous water edge lines of ocean areas based on optical remote sensing images as described in any one of the above-mentioned methods is implemented.

[0016] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for extracting instantaneous water edges of ocean areas based on optical remote sensing images as described in any one of the above is implemented.

[0017] The present invention also provides a computer program product, including a computer program, which, when executed by a processor, implements any of the above-mentioned methods for extracting instantaneous water edges in ocean areas based on optical remote sensing images.

[0018] The present invention provides a method and device for extracting instantaneous water edge lines of ocean areas based on optical remote sensing images. The optical remote sensing images of target ocean areas are acquired, and the ocean water body index of pixels in the optical remote sensing images is calculated to enhance the ocean water body of the optical remote sensing images. Based on the ocean water body index of each pixel, the instantaneous water edge line of the target ocean area is determined by an edge detection algorithm. The extracted instantaneous water edge line is complete and continuous, and the accuracy of the instantaneous water edge line is greatly improved, as well as the automation level and processing efficiency of the instantaneous water edge line extraction are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic flow chart of the method for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images provided by the present invention.

[0021] Figure 2 It is a spectrum curve diagram of ground objects in the method for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images provided by the present invention.

[0022] Figure 3 It is a combined brightness value histogram of the instantaneous water edge extraction method of the ocean area based on optical remote sensing images provided by the present invention.

[0023] Figure 4 It is a band combination ratio histogram of the instantaneous water edge extraction method of the ocean area based on optical remote sensing images provided by the present invention.

[0024] Figure 5 It is a schematic diagram of an optical remote sensing image of a target ocean area in the method for extracting instantaneous water edge lines of an ocean area based on optical remote sensing images provided by the present invention.

[0025] Figure 6 Shows Figure 5 The initial evolution area of ​​the optical remote sensing image is shown.

[0026] Figure 7 yes Figure 5 Schematic diagram of instantaneous water edge extraction results of optical remote sensing images shown.

[0027] Figure 8 yes Figure 5 The schematic diagram of the sea and land segmentation results of the optical remote sensing image after binarization and vectorization is shown.

[0028] Fig. 9 It is a schematic diagram of land-sea segmentation results incorporating geographic information into the instantaneous water edge extraction method for ocean areas based on optical remote sensing images provided by the present invention.

[0029] Fig.10 It is a structural schematic diagram of a device for extracting instantaneous water edge lines in an ocean area based on optical remote sensing images provided by the present invention.

[0030] Fig.11 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Figure 1 FIG. 1 is a flow chart of a method for extracting instantaneous water edge lines in an ocean area based on optical remote sensing images provided by the present invention. Figure 1 As shown, the method includes: Step S1, obtaining an optical remote sensing image of a target ocean area.

[0033] Obtain the optical remote sensing image of the target ocean area. Since the goal is to determine the instantaneous water edge of the target ocean area, the optical remote sensing image of the target ocean area needs to include the ocean area and the continental area, that is, the coastline area.

[0034] Step S2: performing ocean water enhancement on the optical remote sensing image by calculating the ocean water index of the pixels in the optical remote sensing image.

[0035] Pixel, also known as pixel or pixel point, is the smallest unit of digital image. In remote sensing data collection, such as scanning imaging, it is the smallest unit for the sensor to scan and sample the ground scene.

[0036] For the pixels in the optical remote sensing image of the target ocean area, the ocean water index is calculated, which has the ability to distinguish between ocean water and non-water. Therefore, by calculating the ocean water index of the pixel, it is possible to distinguish which pixels are ocean water and which pixels are non-water, thereby achieving ocean water enhancement for the optical remote sensing image.

[0037] Step S3: Based on the ocean water index of each pixel, determine the instantaneous water edge of the target ocean area through an edge detection algorithm.

[0038] Based on the ocean water index of each pixel, the instantaneous water edge of the target ocean area is determined by the edge detection algorithm. The edge detection algorithm can use the Chan-Vese model. The Chan-Vese model is an active contour model based on regional information. The model aims to divide the objects into different sub-regions that do not overlap each other in image segmentation, and on this basis, seek the optimal target edge. In the process of driving curve evolution, the model has good noise resistance and is not affected by the target edge gradient information. It can well process images with noise and weak edges, and the accuracy of the extraction results is greatly improved.

[0039] It has been verified that the instantaneous water edge extracted by the method of the present invention is complete and continuous, and the accuracy of the instantaneous water edge is greatly improved.

[0040] The method for extracting instantaneous water edge lines of ocean areas based on optical remote sensing images provided by the present invention obtains optical remote sensing images of target ocean areas, calculates ocean water body indexes of pixels in the optical remote sensing images, performs ocean water body enhancement on the optical remote sensing images, and determines instantaneous water edge lines of target ocean areas based on the ocean water body indexes of various pixels through an edge detection algorithm. The extracted instantaneous water edge lines are complete and continuous, and the accuracy of the instantaneous water edge lines is greatly improved, as well as the degree of automation and processing efficiency of instantaneous water edge line extraction are improved.

[0041] According to a method for extracting instantaneous water edges in ocean areas based on optical remote sensing images provided by the present invention, the ocean water index is constructed based on the difference between a first brightness value and a second brightness value; wherein the first brightness value is the sum of a blue band brightness value and a green band brightness value, and the second brightness value is the sum of a red band brightness value and a near-infrared band brightness value.

[0042] Determining a good ocean water index to effectively distinguish ocean water from other landforms is the key to improving the accuracy of instantaneous water edge extraction. The present invention determines the ocean water index by conducting experiments on the study area.

[0043] Different land features have different abilities to reflect electromagnetic radiation in different bands due to differences in chemical composition and surface structure. The study area is an ocean area. According to the actual situation of the study area, the land features are mainly divided into two categories: water bodies and non-water bodies. Water bodies refer to ocean water bodies, and non-water bodies include: farmland, buildings, bare land, and forest land.

[0044] Pure pixels are extracted through the Pixel Purity Index (PPI). Pure pixels are pixels containing only one type of ground object. Based on the results of pure pixel extraction by PPI, the pure pixel brightness values ​​of five types of ground objects, namely water bodies, farmlands, buildings, bare land and forest land, in the blue band, green band, red band and near-infrared band are obtained.

[0045] Figure 2 This is a spectrum curve of ground objects in the method for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images provided by the present invention. Figure 2 As shown in the figure, based on remote sensing images, 150 relatively pure pixels of various types of objects are evenly selected to construct spectral curves of various types of objects, showing the average brightness values ​​of various objects in different bands. Table 1 shows the spectral range of various types of objects, and statistics the maximum and minimum values ​​of the spectral values ​​(brightness values) of various types of objects. The spectral differences between water bodies and other objects can be intuitively seen from the chart.

[0046] Table 1 Spectral ranges of various ground objects

[0047] Figure 3 It is a combined brightness value histogram of the instantaneous water edge extraction method of the ocean area based on optical remote sensing images provided by the present invention. Figure 3 It can be seen intuitively in the combined brightness value bar chart shown that for combination 1: the sum of the brightness values ​​of the blue band and the green band, and combination 2: the sum of the brightness values ​​of the red band and the near-infrared band, the difference between the two is the most obvious in the water body. Therefore, the difference between the two can be used to suppress the background objects in the image and highlight the water body.

[0048] Among them, B1 represents the blue band, B2 represents the green band, B3 represents the red band, and B4 represents the near-infrared band.

[0049] Therefore, the sum of the blue band brightness value and the green band brightness value is taken as the first brightness value, and the sum of the red band brightness value and the near-infrared band brightness value is taken as the second brightness value, and the ocean water index can be constructed based on the difference between the first brightness value and the second brightness value. Among them, the ocean water index can be directly taken as the difference between the first brightness value and the second brightness value, or a multiple of the difference between the first brightness value and the second brightness value.

[0050] The present invention provides an instantaneous water edge extraction method for an ocean area based on optical remote sensing images. The method constructs an ocean water body index based on a difference between a first brightness value and a second brightness value. The first brightness value is the sum of a blue band brightness value and a green band brightness value, and the second brightness value is the sum of a red band brightness value and a near-infrared band brightness value. This improves the ability of the ocean water body index to distinguish between ocean water bodies and non-water bodies, thereby further improving the accuracy of instantaneous water edge extraction.

[0051] According to a method for extracting instantaneous water edge lines in an ocean area based on optical remote sensing images provided by the present invention, the ocean water index is expressed as: in, represents the ocean water index, Indicates the brightness value of the blue band. Indicates the brightness value of the green band, Indicates the brightness value of the red band, Represents the brightness value of the near-infrared band.

[0052] When constructing the ocean water index based on the difference between the first brightness value and the second brightness value, the embodiment of the present invention uses the difference between the first brightness value and the second brightness value as the numerator and the sum of the two as the denominator for normalization based on the normalization concept.

[0053] Figure 4 It is a band combination ratio histogram of the instantaneous water edge extraction method of the ocean area based on optical remote sensing images provided by the present invention. Figure 4 It shows five types of landforms: ocean water, farmland, buildings, bare land, and forest land. The value of Figure 4 The significant differences between ocean water and farmland, buildings, bare land and forest land can be seen intuitively, so Can achieve good water enhancement effect.

[0054] The method for extracting instantaneous water edges in ocean areas based on optical remote sensing images provided by the present invention improves the adaptability of the ocean water index by normalizing the expression of the ocean water index, which is conducive to further improving the accuracy of instantaneous water edge extraction.

[0055] According to a method for extracting instantaneous water edges of ocean areas based on optical remote sensing images provided by the present invention, before performing ocean water enhancement on the optical remote sensing images by calculating the ocean water index of pixels in the optical remote sensing images, the method further includes: performing image preprocessing on the optical remote sensing images; wherein the image preprocessing includes radiation calibration, atmospheric correction and orthorectification.

[0056] Before performing ocean water enhancement on the optical remote sensing image by calculating the ocean water index of the pixels in the optical remote sensing image, the optical remote sensing image is preprocessed to improve the quality of the optical remote sensing image. The image preprocessing may include: Radiation calibration: In order to eliminate the error caused by the sensor itself, the radiation brightness value initially obtained by the sensor is inaccurate and needs to be converted into an absolute radiation brightness value, that is, the accurate value transmitted to the sensor entrance.

[0057] Atmospheric correction: Since the image is affected by atmospheric radiation and scattering during imaging, the obtained ground object reflectance value deviates from the true value. If you want to eliminate the interference of atmospheric molecular radiation and scattering on the ground object reflectance and accurately identify the ground object, you must perform atmospheric correction. Atmospheric correction is generally divided into two types, relative atmospheric correction and absolute atmospheric correction. Absolute atmospheric correction simulates the real atmospheric environment and establishes a radiation transmission model to eliminate errors and obtain the true surface reflectance.

[0058] Orthorectification: Use the DEM (Digital Elevation Model) data of the study area to eliminate the errors caused by terrain undulations and sensor geometric distortion, so that the output image is an orthorectified real image and the image geographic coordinates are real coordinates.

[0059] The method for extracting instantaneous water edge lines in an ocean area based on optical remote sensing images provided by the present invention improves the quality of optical remote sensing images by calculating the ocean water index of pixels in the optical remote sensing images and performing image preprocessing including radiation calibration, atmospheric correction and orthorectification before performing ocean water enhancement on the optical remote sensing images, which is beneficial to further improving the accuracy of instantaneous water edge line extraction.

[0060] According to a method for extracting instantaneous water edges in ocean areas based on optical remote sensing images provided by the present invention, after the optical remote sensing images are preprocessed, the method further comprises: denoising the optical remote sensing images by minimum noise separation transformation.

[0061] After preprocessing the optical remote sensing images, the optical remote sensing images can be denoised through the minimum noise fraction rotation (MNF Rotation) to further improve the quality of the optical remote sensing images.

[0062] The minimum noise separation transform can be performed in two steps: The first step is to filter the image using a high-pass filter; The second step is to perform standard principal component transformation on the noise data.

[0063] Through the above two steps, the MNF transformation matrix can be obtained. In the vector obtained after the transformation, there is no correlation between each element. The amount of data information in different bands is different. The increase in dimension will lead to a decrease in the amount of information. At the same time, the data is sorted from large to small according to the signal-to-noise ratio to reduce the impact of noise on the data. Not only does it remove the impact of noise, but it also well preserves the ground object information and the spectral differences between them, providing good data for further research on the spectral information of different ground objects.

[0064] The method for extracting instantaneous water edge lines in an ocean area based on optical remote sensing images provided by the present invention further improves the quality of optical remote sensing images by denoising the optical remote sensing images through minimum noise separation transformation after image preprocessing, which is beneficial to further improve the accuracy of instantaneous water edge line extraction.

[0065] According to a method for extracting the instantaneous water edge of an ocean area based on optical remote sensing images provided by the present invention, before determining the instantaneous water edge of the target ocean area through an edge detection algorithm, the method also includes: setting an initial evolution area of ​​the edge detection algorithm; wherein the initial evolution area is located near the sea-land boundary.

[0066] Before determining the instantaneous water edge of the target ocean area by the edge detection algorithm, the initial evolution region of the edge detection algorithm is set, and the initial contour is gradually evolved to the boundary of the ocean water area. The initial evolution region can be set near the sea-land boundary to reduce the number of iterations and improve the operation efficiency. Among them, the initial evolution region set near the sea-land boundary can include a part of the ocean area and a part of the land area.

[0067] Figure 5 It is a schematic diagram of an optical remote sensing image of a target ocean area in the method for extracting instantaneous water edge lines of an ocean area based on optical remote sensing images provided by the present invention.

[0068] Figure 6 Shows Figure 5 The initial evolution area of ​​the optical remote sensing image shown in . Figure 6As shown, the initial evolution area is set near the sea-land boundary.

[0069] Figure 7 yes Figure 5 The schematic diagram of the instantaneous water edge extraction result of the optical remote sensing image is shown in FIG. Figure 7 As shown, after the ocean water body enhancement and the initial evolution area setting, the instantaneous water edge is obtained through iterative processing of the edge detection algorithm.

[0070] The instantaneous water edge extraction method of an ocean area based on optical remote sensing images provided by the present invention improves processing efficiency by setting an initial evolution area of ​​an edge detection algorithm near the sea-land boundary before determining the instantaneous water edge of a target ocean area through an edge detection algorithm.

[0071] According to a method for extracting instantaneous water edges of ocean areas based on optical remote sensing images provided by the present invention, after determining the instantaneous water edges of the target ocean area by an edge detection algorithm, the method further includes: obtaining a sea-land segmentation result based on the instantaneous water edges; and binarizing the sea-land segmentation result.

[0072] After the instantaneous water edge of the target ocean area is determined by the edge detection algorithm, the ocean area and the non-ocean area can be determined according to the instantaneous water edge, thereby obtaining the sea-land segmentation result bounded by the instantaneous water edge.

[0073] To facilitate viewing of the land-sea segmentation results, the land-sea segmentation results can be binarized. For example, to highlight the ocean area, the instantaneous water edge can be set to 1 and the rest can be set to 0. At the same time, since part of the remote sensing image of the target ocean area is the ocean, the image cannot display the entire ocean boundary. Therefore, in addition to the instantaneous water edge, part of the water boundary of the image can also be extracted and set to 1 to jointly represent the ocean area.

[0074] The instantaneous water edge extraction method for an ocean area based on optical remote sensing images provided by the present invention obtains a land-sea segmentation result according to the instantaneous water edge, performs binarization processing on the land-sea segmentation result, and improves the display effect of the land-sea segmentation result.

[0075] According to a method for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images provided by the present invention, after binarizing the land-sea segmentation result, the method further comprises: vectorizing the land-sea segmentation result.

[0076] The land-sea segmentation result after binary processing can also be further vectorized. Vectorizing the land-sea segmentation result allows it to be edited, which provides convenience for subsequent work.

[0077] Figure 8 yes Figure 5 The schematic diagram of the sea and land segmentation results of the optical remote sensing image after binarization and vectorization is shown.

[0078] The instantaneous water edge extraction method of the ocean area based on optical remote sensing images provided by the present invention facilitates the subsequent processing of the sea-land segmentation results by vectorizing the sea-land segmentation results after binarizing the sea-land segmentation results.

[0079] According to a method for extracting instantaneous waterside lines in an ocean area based on optical remote sensing images provided by the present invention, the land-sea segmentation result retains the geographic information of the optical remote sensing images.

[0080] For the land and sea segmentation results obtained based on the instantaneous water edge, the geographic information of the image, such as longitude and latitude information, is integrated based on GIS technology to facilitate the subsequent application of the instantaneous water edge, such as using ArcGIS software to analyze the results.

[0081] Fig. 9 It is a schematic diagram of land-sea segmentation results incorporating geographic information into the instantaneous water edge extraction method for ocean areas based on optical remote sensing images provided by the present invention.

[0082] The instantaneous water edge extraction method for an ocean area based on an optical remote sensing image provided by the present invention retains the geographic information of the optical remote sensing image through the sea-land segmentation result, thus facilitating the subsequent application of the instantaneous water edge.

[0083] The present invention provides an automatic extraction method for instantaneous waterside with high automation and good extraction effect, so as to overcome the problems commonly existing in the extraction of instantaneous waterside, such as incomplete and discontinuous results, low extraction efficiency, low intelligence, and lack of practicality. It can be seen from the instantaneous waterside extraction process constructed by the present invention that the extraction of the instantaneous waterside can be quickly completed by only specifying the initial evolution area for the model, and the arbitrary selection of the initial evolution area (which can be arbitrarily selected near the sea-land boundary to improve processing efficiency) also brings convenience to the use of the model, greatly improves the automation of the instantaneous waterside extraction, and improves efficiency. In addition, the final instantaneous waterside extraction result does not have the problem of broken lines or missing lines, and the result is complete and continuous, which greatly improves the accuracy of the instantaneous waterside, and improves the automation and processing efficiency of the instantaneous waterside extraction.

[0084] The instantaneous water edge extraction device for an ocean area based on optical remote sensing images provided by the present invention is described below. The instantaneous water edge extraction device for an ocean area based on optical remote sensing images described below and the instantaneous water edge extraction method for an ocean area based on optical remote sensing images described above can be referred to each other.

[0085] Fig.10Schematic diagram of the structure of the instantaneous water edge extraction device for ocean areas based on optical remote sensing images provided by the present invention. Fig.10 As shown, the device includes an acquisition module 10, an enhancement module 20 and a determination module 30, wherein: the acquisition module 10 is used to acquire an optical remote sensing image of a target ocean area; the enhancement module 20 is used to enhance the ocean water body of the optical remote sensing image by calculating the ocean water body index of the pixels in the optical remote sensing image; the determination module 30 is used to determine the instantaneous water edge of the target ocean area through an edge detection algorithm based on the ocean water body index of each pixel.

[0086] The device for extracting instantaneous water edge lines of ocean areas based on optical remote sensing images provided by the present invention acquires optical remote sensing images of target ocean areas, calculates ocean water body indexes of pixels in the optical remote sensing images, performs ocean water body enhancement on the optical remote sensing images, and determines the instantaneous water edge lines of the target ocean areas through an edge detection algorithm based on the ocean water body indexes of the pixels, thereby greatly improving the accuracy of instantaneous water edge line extraction, and improving the degree of automation and processing efficiency of instantaneous water edge line extraction.

[0087] Fig.11 An example of a physical structure diagram of an electronic device is shown in FIG. Fig.11 As shown, the electronic device may include: a processor 1010, a communication interface 1020, a memory 1030 and a communication bus 1040, wherein the processor 1010, the communication interface 1020 and the memory 1030 communicate with each other through the communication bus 1040. The processor 1010 may call the logic instructions in the memory 1030 to execute the method for extracting the instantaneous water edge of the ocean area based on the optical remote sensing image, the method comprising: acquiring the optical remote sensing image of the target ocean area; performing ocean water enhancement on the optical remote sensing image by calculating the ocean water index of the pixel in the optical remote sensing image; and determining the instantaneous water edge of the target ocean area by an edge detection algorithm based on the ocean water index of each pixel.

[0088] In addition, the logic instructions in the above-mentioned memory 1030 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0089] On the other hand, the present invention also provides a computer program product, which includes a computer program, and the computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the instantaneous water edge extraction method of the ocean area based on the optical remote sensing image provided by the above-mentioned methods, and the method includes: obtaining an optical remote sensing image of the target ocean area; enhancing the ocean water body of the optical remote sensing image by calculating the ocean water body index of the pixel in the optical remote sensing image; and determining the instantaneous water edge of the target ocean area by an edge detection algorithm based on the ocean water body index of each pixel.

[0090] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the method for extracting instantaneous water edges of ocean areas based on optical remote sensing images provided by the above-mentioned methods, the method comprising: acquiring an optical remote sensing image of a target ocean area; enhancing the ocean water body of the optical remote sensing image by calculating the ocean water body index of pixels in the optical remote sensing image; and determining the instantaneous water edge of the target ocean area by an edge detection algorithm based on the ocean water body index of each pixel.

[0091] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0092] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images, characterized in that: include: Acquire optical remote sensing images of target ocean areas; Performing ocean water enhancement on the optical remote sensing image by calculating the ocean water index of the pixels in the optical remote sensing image; Based on the ocean water index of each of the pixels, the instantaneous water edge of the target ocean area is determined by an edge detection algorithm.

2. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 1 is characterized in that: The ocean water index is constructed based on the difference between a first brightness value and a second brightness value; wherein the first brightness value is the sum of the blue band brightness value and the green band brightness value, and the second brightness value is the sum of the red band brightness value and the near-infrared band brightness value.

3. According to the method for extracting instantaneous water edge of ocean area based on optical remote sensing images according to claim 2, the ocean water index is expressed as: in, represents the ocean water index, Indicates the brightness value of the blue band, Indicates the brightness value of the green band, Indicates the brightness value of the red band, Represents the brightness value of the near-infrared band.

4. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 1, characterized in that: Before performing ocean water enhancement on the optical remote sensing image by calculating the ocean water index of the pixel in the optical remote sensing image, the method further comprises: The optical remote sensing image is subjected to image preprocessing; wherein the image preprocessing includes radiation calibration, atmospheric correction and orthorectification.

5. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 4 is characterized in that: After performing image preprocessing on the optical remote sensing image, the method further includes: The optical remote sensing image is denoised by minimum noise separation transformation.

6. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 1, characterized in that: Before determining the instantaneous water edge of the target ocean area by an edge detection algorithm, the method further includes: An initial evolution region of the edge detection algorithm is set; wherein the initial evolution region is located near the sea-land boundary.

7. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 1, characterized in that: After determining the instantaneous water edge of the target ocean area by the edge detection algorithm, the method further includes: Acquire a sea-land segmentation result according to the instantaneous water edge; The land-sea segmentation result is binarized.

8. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 7 is characterized in that: After the sea-land segmentation result is binarized, the method further includes: Vectorization is performed on the land-sea segmentation result.

9. The method for extracting instantaneous water edge of an ocean area based on optical remote sensing images according to claim 7, characterized in that: The land-sea segmentation result retains the geographic information of the optical remote sensing image.

10. A device for extracting instantaneous water edge lines in ocean areas based on optical remote sensing images, characterized in that: include: An acquisition module is used to: acquire optical remote sensing images of a target ocean area; An enhancement module, used to: perform ocean water enhancement on the optical remote sensing image by calculating the ocean water index of the pixels in the optical remote sensing image; The determination module is used to determine the instantaneous water edge of the target ocean area through an edge detection algorithm based on the ocean water index of each pixel.

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