Rapid estimation method for spatial distribution of land efficiency

Abstract

The invention discloses a rapid estimation method and system for land efficiency spatial distribution, which are applied to the technical field of spatial geographic information data processing, and geometric correction is performed on a remote sensing image of time-phase remote sensing data by obtaining the time-phase remote sensing data of a to-be-evaluated region; according to the population thermodynamic diagram, performing boundary correction on the planned land boundary on the night light image to obtain a corrected boundary; cutting the corrected night light image of the corresponding area through the correction boundary; calculating the total amount of night light radiation in each planning land use range; by using the population thermodynamic diagram with a high sampling rate, an evaluation region area distortion problem caused by low data acquisition frequency of the stable night light image data set is accurately corrected, and the estimation accuracy is improved. The improvement enables the smoothness of the stable light irradiation boundary to be enhanced, thereby improving the speed and precision of land estimation.

Description

Technical Field

[0001] The invention relates to the technical field of spatial geographic information data processing, and in particular to a method for quickly estimating the spatial distribution of land efficiency. Background Art

[0002] At present, there are two main methods for measuring traditional land efficiency: the first method is to calculate the planned land output efficiency of each administrative unit based on administrative units at all levels, combined with non-agricultural GDP statistics and planned land statistics. However, this method cannot reflect the efficiency distribution within the administrative unit, and the difficulty in collecting statistical data for administrative units below the county level limits the in-depth study of the spatial distribution of planned land efficiency in these small-scale regions. The second method is to obtain planned land efficiency through field surveys based on specific plots. Although this method can provide more accurate data, it is labor-intensive and not suitable for large-scale dynamic research. At the same time, differences in survey standards and participant response levels may also affect the accuracy of GDP data. Therefore, it is urgent to use new spatial information technology to reasonably allocate regional statistical non-agricultural GDP data to smaller spatial units to achieve rapid estimation of the spatial distribution of regional planned land efficiency.

[0003] Therefore, in order to estimate the spatial distribution of land efficiency efficiently and quickly, for example, a method for quickly estimating the spatial distribution of planned land efficiency is provided by the Chinese invention patent with announcement number CN106156756B, which uses TM image data and DMSP / OLS night light data to obtain the spatial distribution information of the planned land and the total amount of night light radiation on the area to be evaluated, and uses the spatial mapping relationship between the total amount of night light radiation and non-agricultural GDP to spread the non-agricultural GDP statistical values ​​of the area to be evaluated to small spatial units, thereby quickly estimating the spatial distribution of regional planned land efficiency. Combining TM remote sensing image data with night light data can overcome the drawbacks of overestimation of light area caused by the spillover effect of night light data, and has obvious advantages in estimation speed, accuracy and method universality compared with previous technical methods. However, in the actual processing of spatial geographic information, there are a lot of discontinuities and oversaturation problems in the time period of the rapidly changing nighttime planned land area due to the low frequency of data acquisition of stable nighttime light image data sets. If we only rely on the light area caused by the spillover effect of nighttime light data for estimation, especially at the boundary of the planned land, the actual impact range of the stable nighttime light will be distorted, thereby reducing the accuracy of estimating the actual irradiation impact range of the stable nighttime light. Summary of the invention The purpose of the present invention is to propose a method and system for quickly estimating the spatial distribution of land efficiency, so as to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0004] In order to achieve the above object, according to one aspect of the present invention, a method for quickly estimating the spatial distribution of land efficiency is provided, the method comprising the following steps: S100, acquiring temporal remote sensing data of the area to be evaluated, and performing geometric correction on the remote sensing image of the temporal remote sensing data; S200, obtaining a night light image and a population heat map of the area to be evaluated, and performing image registration on the night light image, the population heat map and the remote sensing image; S300, marking the planned land boundaries at each time phase in the remote sensing image; S400, performing boundary correction on the planned land boundary on the night light image according to the population heat map to obtain a corrected boundary; S500, obtaining night light data within the planned land area in the area to be evaluated by cutting the corrected night light image of the corresponding area through the corrected boundary; S600, calculating the total amount of nighttime light radiation within each planned land area.

[0005] Further, in S400, the population heat map is any one of a mobile phone messaging population heat map, a WeChat travel population heat map, a Baidu map population heat map, and a Baidu Huiyan data population heat map.

[0006] Among them, the method for image registration is to use the remote sensing image as the reference image, construct the correspondence between the reference image and the geographic coordinates, and respectively register the night light image and population heat map with the reference image.

[0007] Among them, the night light image is the DMSP / OLS stable night light image dataset.

[0008] Among them, the calculation method of the total amount of night light radiation within the planned land area is: the total amount of night light radiation within the planned land area is the product of the planned land area and the average stable light intensity data derived from the stable light value part of the night light image of each spatial unit within the planned land area.

[0009] The spatial unit is a tetrahedral unit or a hexahedral unit divided by meshing or fishnet segmentation.

[0010] It also includes obtaining the spatial distribution information of the total amount of nighttime light radiation within each planned land area.

[0011] Among them, the method for obtaining the spatial distribution information of the total amount of night light radiation within each planned land area is: using the spatial mapping relationship between the total amount of night light radiation and the non-agricultural GDP statistical value in the planned land area, the non-agricultural GDP statistical value of each planned land area in the area to be evaluated is spread to each planned land area.

[0012] Among them, the calculation method of the non-agricultural GDP statistical value within the planned land area is: the non-agricultural GDP statistical value is the product of the non-agricultural GDP statistical value of the entire area to be evaluated and the first ratio; among them, the first ratio is: the ratio of the total amount of night-time light radiation within the planned land area to the total amount of night-time light radiation within the planned land area in the entire area to be evaluated.

[0013] Preferably, the spatial distribution information of the total amount of nighttime light radiation is obtained according to a method for obtaining spatial distribution information of the total amount of nighttime light radiation in a method for rapidly estimating spatial distribution of planned land use efficiency provided by Chinese invention patent with announcement number CN106156756B.

[0014] Preferably, the method for obtaining the spatial distribution information of the total amount of nighttime light radiation within each planned land area is: By utilizing the spatial mapping relationship between the total amount of night light radiation in the planned land area and the effective buildings in the planned land, the effective buildings in the planned land of each planned land area in the area to be evaluated are distributed to each planned land area.

[0015] Among them, the calculation method of effective buildings in the planned land within the planned land scope is: the effective buildings are the product of the number of buildings in the entire area to be evaluated and the second ratio, wherein the second ratio is: the total number of planned land in the area to be evaluated is N2, the number of planned land in the area to be evaluated whose total amount of night light radiation is greater than the average amount of night light radiation in all planned lands is N1, and the ratio of N1 to N2 is used as the second ratio.

[0016] The existing land efficiency assessment methods based on night light images usually directly or indirectly rely on the scope of night light illumination to judge land planning efficiency. However, since the light is not effectively evenly distributed in a specific area or is not fully utilized due to the time-space relationship, this phenomenon may not only lead to misjudgment of night light intensity, causing the actual brightness of some areas to be overestimated or underestimated, but also because the data acquisition frequency of the stable night light image dataset is low (the cycle is 101 minutes), resulting in discontinuity and oversaturation problems in time periods in rapidly changing nighttime urban areas (for example, the difference between the high-brightness time period and the low-brightness sleep time period in the residential area will produce large discontinuity and oversaturation problems, see reference: Zhang Mengqi et al. Correction method of DMSP / OLS stable night light image [J]. Bulletin of Surveying and Mapping, 2017(12):6.DOI:10.13474 / j.cnki.11-2246.2017.0379). These factors make it impossible to timely and accurately reflect the impact of stable nighttime lights on the radiation range of land use. Since the population heat map is updated every 5-15 minutes, it is a population density distribution map obtained by statistical analysis of the location information of mobile phone users. Therefore, the population heat map will not affect the population gathering area during the night rest period. Therefore, this application uses the population heat map with a faster update frequency and is not easily affected to correct the radiation impact range of the planned land boundary in the nighttime light image, specifically: Furthermore, in S400, the method of performing boundary correction on the planned land boundary on the night light image according to the population heat map to obtain the corrected boundary includes: Perform edge detection on the grayscale population heat map to obtain regions composed of multiple edge lines, record the average grayscale value of all pixels in each region as the contrast grayscale, and record the region in each region where the average grayscale value is greater than the contrast grayscale as a population high heat area; (Since the color of a place with a relatively large population on the population heat map is reddish, it appears brighter after the grayscale population heat map is converted, so the population high heat area is a place with a relatively large population); According to the acquisition time of the night light images, the population heat maps collected at the corresponding time of each night light image are judged in sequence: if a population high heat area that does not appear in the corresponding position of the population heat map collected last time appears in each planned land boundary area of ​​the current population heat map, the position of the population high heat area is recorded as a population cluster area; The population heat map corresponding to the population cluster area is used as the initial aggregation area of ​​the boundary area of ​​the current planned land (that is, the area where local population aggregation is first monitored in the boundary area of ​​the current planned land), and the point with the largest gray value in the population cluster area is used as the mark point; If there is a high-heat population area other than the population cluster area on the population heat map collected last time in the initial cluster area, then the point with the largest gray value in the high-heat population area other than the population cluster area on the population heat map collected last time with the largest distance from the mark is the anchor point; the high-heat population area where the anchor point is located is the associated cluster area; The average gray value of each point on the edge line of the initial clustering area is A1; the average gray value of each point on the edge line of the associated clustering area is A2; Take the point on the edge line of the initial clustering area with a gray value greater than A1 that is closest to the edge line of the associated clustering area as the anchor point, and take the point on the edge line of the associated clustering area with a gray value greater than A2 that is closest to the edge line of the initial clustering area as the calibration point; take the straight line passing through the anchor point and the anchor point as L1; take the straight line passing through the calibration point and the calibration point as L2; ​​take the area between L1 and L2 on the population heat map as the population change scanning area of ​​the boundary area of ​​the current planned land; (Since the population heat map is updated frequently, it will bring greater algorithm complexity to real-time scanning. In actual scanning, the comprehensive scanning speed is slow. In order to speed up the population thermal change scanning speed in subsequent steps, a population change scanning area with the most obvious population thermal change regional characteristics, which is composed of points on the edges of two significant areas with continuous correlation and close changes, is required to reduce the algorithm complexity and thus speed up the scanning speed); In each planned land boundary area, if there is a population hotspot in the population change scanning area passing through the planned land boundary area that meets the discontinuous duration condition, the planned land boundary of the planned land boundary area is marked as a boundary to be repaired; boundary correction is performed on the boundary to be repaired to obtain a corrected boundary.

[0017] Specifically, the discontinuous duration condition is: in the population change scanning area, if the average value of the stable light intensity in the corresponding area of ​​the night light image collected at the corresponding time in the current population hot zone is less than the average value of the stable light intensity in the corresponding area of ​​the night light image in the initial gathering area in the planned land boundary area, then the current population hot zone is marked as meeting the discontinuous condition. (That is, in the current population change scanning area, meeting the discontinuous condition means that the change of stable light intensity is abnormal, which is obviously caused by the relatively low data acquisition frequency of the stable night light image data set and the discontinuity and oversaturation caused by the time period change of the rapidly changing night urban area, so the corresponding planned land boundary is affected).

[0018] Although the above method can quickly scan out most of the boundaries affected by abnormal radiation changes in stable light intensity, if the population hotspot disappears quickly (the speed of disappearance is less than the first appearance interval speed in the population change scanning area), there will still be a problem of unsaturated scanning due to the large sampling rate of the stable night light image data set, especially at the boundary of the planned land, the actual influence range of the stable night light will be distorted, so that the actual time influence range of the stable light radiation cannot be scanned in certain time periods. In order to solve this problem, this application proposes the following solutions: Preferably, the discontinuous duration condition is: the time when the current population high-heat area first appears (i.e., the population heat map collection time corresponding to the first appearance of the population high-heat area on the population heat map) is recorded as the start time ST; in the population change scanning area, the time from the first appearance of the initial gathering area in the planned land boundary area to the start time ST of the current population high-heat area is the radiation start time; the time from the moment after the start time ends to the moment when the average grayscale value of all points on the edge line of the current population high-heat area is first greater than the contrast grayscale or A1 is the radiation reduction time; if the radiation reduction time is less than the radiation start time, the average value of the stable light intensity in the corresponding area of ​​the night light image collected at the corresponding moment of the current population high-heat area is less than the average value of the stable light intensity of the initial gathering area in the corresponding area of ​​the night light image, then the current population high-heat area is marked as satisfying the discontinuous condition. (That is, in the current population change scanning area, when the duration of radiation reduction is shorter than the duration of radiation activation, a shorter duration of light radiation is suddenly generated. This is obviously a large and unreasonable change in the light irradiation range at the geographical location corresponding to the population concentration area. Since the population heat map is updated every 5-15 minutes, it is a population density distribution map obtained by statistical analysis of the location information of mobile phone users. Therefore, the population heat map will not affect the population concentration area during the night rest period. The above discontinuous condition uses this law to identify the boundary of the light irradiation range that has changed in the population concentration area due to the low frequency of data acquisition of the night light image data set. Therefore, this discontinuous condition indicates that the stable light intensity has changed abnormally, thereby affecting the accuracy of the planned land boundary and failing to timely reflect the land use scope affected by the range assessment of the light irradiation. Therefore, judging the discontinuous duration condition can accurately identify the distorted boundary affected by the range of light irradiation due to the low frequency of data acquisition of the night light image data set).

[0019] In S400, the method for performing boundary correction on the boundary to be repaired to obtain the corrected boundary is: The point with the largest stable light intensity in the corresponding area of ​​the high-heat population zone that meets the discontinuous condition in the boundary area of ​​the planned land is P1, and the point with the smallest stable light intensity is P2; the point with the smallest difference in stable light intensity with P1 on the boundary to be repaired is P3, and the point with the smallest difference in stable light intensity with P2 on the boundary to be repaired is P4; the shortest curve segment passing through P3 and P4 on the boundary to be repaired is the repair curve; the extracted curve passing through P1 and P2 on the boundary of the corresponding area of ​​the high-heat population zone that meets the discontinuous condition in the boundary area of ​​the planned land is used; the repair curve on the boundary to be repaired is deleted; the extracted curve is rotated according to the repair curve and enlarged proportionally, the extracted curve is spliced ​​at the position of the deleted repair curve, and the boundary to be repaired at this time is recorded as the corrected boundary.

[0020] The rotation angle is the angle between the straight line passing through P1 and P2 and the straight line passing through P3 and P4.

[0021] Through the above method, the stable light intensity characteristics of the high-population hotspots that meet the discontinuous conditions within the boundary area of ​​the planned land are used, and the characteristics of irradiation from high to low are used to adjust the boundary curve segments with large difference changes in stable light intensity on the restoration boundary. This process effectively corrects the distortion of the assessment area caused by the influence of erroneous light irradiation due to the low frequency of data acquisition, thereby improving the accuracy of the estimation. In addition, the preferred correction method finds the corresponding area of ​​the high-population hotspot that is closer to the boundary to be restored by screening the average stable light intensity of the initial cluster area and the associated cluster area boundary, thereby further improving the smoothness of the boundary to be restored affected by stable light irradiation.

[0022] Preferably, in S400, the method for performing boundary correction on the boundary to be repaired to obtain the corrected boundary is: The corresponding area of ​​the high-heat population area in the planned land boundary area that meets the discontinuous condition and has the largest average value of stable light intensity is obtained as the source area; the corresponding area of ​​the high-heat population area in the planned land boundary area that meets the discontinuous condition and has the smallest average value of stable light intensity is obtained as the target area; The difference between the average stable light intensity of all points on the boundary of the initial clustering area and the boundary to be repaired is recorded as the initial intensity; the difference between the average stable light intensity of all points on the boundary of the associated clustering area and the boundary to be repaired is recorded as the associated intensity; If the initial intensity is greater than the associated intensity, the boundary line of the source area is recorded as the extraction boundary, otherwise the boundary line of the target area is recorded as the extraction boundary; the point with the largest stable light intensity on the extraction boundary is BP, the point with the smallest stable light intensity is SP, and the shortest curve segment passing through BP and SP on the extraction boundary is the extraction curve; The point with the largest stable light intensity on the boundary to be repaired is BP1, the point with the smallest stable light intensity is SP1, and the shortest curve segment passing through BP1 and SP1 on the boundary to be repaired is the curve to be repaired; the curve to be repaired on the boundary to be repaired is deleted; The extracted curve is rotated according to the curve to be repaired and enlarged in equal proportion, and the extracted curve is spliced ​​at the position of the deleted curve to be repaired, and the boundary to be repaired at this time is recorded as the correction boundary.

[0023] The rotation angle is the angle between the straight line passing through BP and SP and the straight line passing through BP1 and SP1.

[0024] The present invention also provides a system for quickly estimating the spatial distribution of land efficiency, the system comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the computer program in the following system units: A remote sensing acquisition unit is used to obtain the temporal remote sensing data of the area to be evaluated and to perform geometric correction on the remote sensing image of the temporal remote sensing data; An image registration unit is used to obtain nighttime light images and population heat maps of the area to be evaluated, and to perform image registration on the nighttime light images, population heat maps and remote sensing images; Boundary annotation unit, used to annotate the planned land boundaries at each time phase in the remote sensing image; A boundary correction unit is used to correct the boundary of the planned land on the night light image according to the population heat map to obtain a corrected boundary; A boundary cutting unit is used to obtain night light data within the planned land area in the area to be evaluated by cutting the corrected night light image of the corresponding area through the corrected boundary; The radiation calculation unit is used to calculate the total amount of night light radiation within the scope of each planned land.

[0025] The beneficial effects of the present invention are as follows: the present invention provides a method and system for quickly estimating the spatial distribution of land efficiency, which addresses the discontinuity and oversaturation problems caused by the low data acquisition frequency of a stable nighttime light image data set, resulting in distortion in estimating the light area. It can timely reflect the scope of land use affected by the range assessment of the light radiation influence, accurately redefine the boundaries of the range of light radiation influence, ensure the actual accuracy of the light radiation influence range, and by reducing the algorithm complexity, speed up the scanning speed and thus improve the land estimation speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other features of the present invention will become more obvious by describing in detail the embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings of the present invention represent the same or similar elements. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative work. In the accompanying drawings: Figure 1 Shown is a flow chart of a method for rapid estimation of spatial distribution of land efficiency; Figure 2 The figure shows a grayscale population heat map of a certain place; Figure 3 Shown is a nighttime light image of a certain place; Figure 4 Shown is a structural diagram of a system for rapid estimation of spatial distribution of land efficiency. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments and drawings to clearly and completely describe the concept, specific structure and technical effects of the present invention, so as to fully understand the purpose, scheme and effect of the present invention. It should be noted that the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0028] Example 1 like Figure 1 The flowchart of a method for quickly estimating the spatial distribution of land efficiency according to the present invention is shown below. Figure 1 A method for quickly estimating the spatial distribution of land efficiency according to an embodiment of the present invention is described below.

[0029] The present invention proposes a method for quickly estimating the spatial distribution of land efficiency, which specifically includes the following steps: S100, acquiring temporal remote sensing data of the area to be evaluated, and performing geometric correction on the remote sensing image of the temporal remote sensing data; S200, obtaining a night light image and a population heat map of the area to be evaluated, and performing image registration on the night light image, the population heat map and the remote sensing image; S300, marking the planned land boundaries at each time phase in the remote sensing image; S400, performing boundary correction on the planned land boundary on the night light image according to the population heat map to obtain a corrected boundary; S500, obtaining night light data within the planned land area in the area to be evaluated by cutting the corrected night light image of the corresponding area through the corrected boundary; S600, calculating the total amount of nighttime light radiation within each planned land area.

[0030] Further, in S400, the population heat map is a mobile phone messaging population heat map.

[0031] Among them, the method for image registration is to use the remote sensing image as the reference image, construct the correspondence between the reference image and the geographic coordinates, and respectively register the night light image and population heat map with the reference image.

[0032] Among them, the night light image is the DMSP / OLS stable night light image dataset.

[0033] Among them, the calculation method of the total amount of night light radiation within the planned land area is: the total amount of night light radiation within the planned land area is the product of the planned land area and the average stable light intensity data derived from the stable light value part of the night light image of each spatial unit within the planned land area.

[0034] The space unit is a tetrahedral unit divided by a grid.

[0035] It also includes obtaining the spatial distribution information of the total amount of nighttime light radiation within each planned land area.

[0036] Among them, the method for obtaining the spatial distribution information of the total amount of night light radiation within each planned land area is: using the spatial mapping relationship between the total amount of night light radiation and the non-agricultural GDP statistical value in the planned land area, the non-agricultural GDP statistical value of each planned land area in the area to be evaluated is spread to each planned land area.

[0037] Among them, the calculation method of the non-agricultural GDP statistical value within the planned land area is: the non-agricultural GDP statistical value is the product of the non-agricultural GDP statistical value of the entire area to be evaluated and the first ratio; among them, the first ratio is: the ratio of the total amount of night-time light radiation within the planned land area to the total amount of night-time light radiation within the planned land area in the entire area to be evaluated.

[0038] Preferably, the spatial distribution information of the total amount of nighttime light radiation is obtained according to a method for obtaining spatial distribution information of the total amount of nighttime light radiation in a method for rapidly estimating spatial distribution of planned land use efficiency provided by Chinese invention patent with announcement number CN106156756B.

[0039] Furthermore, in S400, the method of performing boundary correction on the planned land boundary on the night light image according to the population heat map to obtain the corrected boundary includes: like Figure 2 The figure shows the grayscale population heat map. The grayscale population heat map is subjected to edge detection to obtain regions formed by multiple edge lines. The average grayscale value of all pixels in each region is recorded as the contrast grayscale. The region in each region where the average grayscale value is greater than the contrast grayscale is recorded as a population high heat region. like Figure 3 The figure shows night light images. According to the acquisition time of the night light images, the population heat maps collected at the corresponding time of each night light image are judged in sequence: if a population high heat area that does not appear in the corresponding position of the population heat map collected last time appears in each planned land boundary area of ​​the current population heat map, the position of the population high heat area is recorded as a population cluster area; The population heat map corresponding to the population cluster area is used as the initial aggregation area of ​​the boundary area of ​​the current planned land use, and the point with the largest gray value in the population cluster area is used as the punctuation point; If there is a high-heat population area other than the population cluster area on the population heat map collected last time in the initial cluster area, then the point with the largest gray value in the high-heat population area other than the population cluster area on the population heat map collected last time with the largest distance from the mark is the anchor point; the high-heat population area where the anchor point is located is the associated cluster area; The average gray value of each point on the edge line of the initial clustering area is A1; the average gray value of each point on the edge line of the associated clustering area is A2; Take the point closest to the edge line of the associated clustering area among the points on the edge line of the initial clustering area with a grayscale value greater than A1 as the anchor point, and take the point closest to the edge line of the initial clustering area among the points on the edge line of the associated clustering area with a grayscale value greater than A2 as the calibration point; take the straight line passing through the anchor point and the anchor point as L1; take the straight line passing through the calibration point and the calibration point as L2; ​​take the area between L1 and L2 on the population heat map as the population change scanning area of ​​the boundary area of ​​the current planned land use; In each planned land boundary area, if there is a population hotspot in the population change scanning area passing through the planned land boundary area that meets the discontinuous duration condition, the planned land boundary of the planned land boundary area is marked as a boundary to be repaired; boundary correction is performed on the boundary to be repaired to obtain a corrected boundary.

[0040] Specifically, the discontinuous duration condition is: in the population change scanning area, if the average value of the stable light intensity in the corresponding area of ​​the night light image collected at the corresponding time of the current population hot zone is less than the average value of the stable light intensity in the corresponding area of ​​the night light image of the initial gathering area in the planned land boundary area, then the current population hot zone is marked as meeting the discontinuous condition.

[0041] In S400, the method for performing boundary correction on the boundary to be repaired to obtain the corrected boundary is: The point with the largest stable light intensity in the corresponding area of ​​the high-heat population zone that meets the discontinuous condition in the boundary area of ​​the planned land is P1, and the point with the smallest stable light intensity is P2; the point with the smallest difference in stable light intensity with P1 on the boundary to be repaired is P3, and the point with the smallest difference in stable light intensity with P2 on the boundary to be repaired is P4; the shortest curve segment passing through P3 and P4 on the boundary to be repaired is the repair curve; the extracted curve passing through P1 and P2 on the boundary of the corresponding area of ​​the high-heat population zone that meets the discontinuous condition in the boundary area of ​​the planned land is used; the repair curve on the boundary to be repaired is deleted; the extracted curve is rotated according to the repair curve and enlarged proportionally, the extracted curve is spliced ​​at the position of the deleted repair curve, and the boundary to be repaired at this time is recorded as the corrected boundary.

[0042] The rotation angle is the angle between the straight line passing through P1 and P2 and the straight line passing through P3 and P4.

[0043] Example 2 This embodiment 2 replaces the following method based on embodiment 1, specifically: Preferably, the discontinuous duration condition is: the time when the current population high-heat area first appears (i.e., the population heat map collection time corresponding to the first appearance of the population high-heat area on the population heat map) is recorded as the start time ST; in the population change scanning area, the time from the first appearance of the initial gathering area in the planned land boundary area to the start time ST of the current population high-heat area is the radiation start time; the time from the moment after the start time ends to the moment when the average grayscale value of all points on the edge line of the current population high-heat area is first greater than the contrast grayscale or A1 is the radiation reduction time; if the radiation reduction time is less than the radiation start time, the average value of the stable light intensity in the corresponding area of ​​the night light image collected at the corresponding moment of the current population high-heat area is less than the average value of the stable light intensity of the initial gathering area in the corresponding area of ​​the night light image, then the current population high-heat area is marked as satisfying the discontinuous condition.

[0044] Preferably, in S400, the method for performing boundary correction on the boundary to be repaired to obtain the corrected boundary is: The corresponding area of ​​the high-heat population area in the planned land boundary area that meets the discontinuous condition and has the largest average value of stable light intensity is obtained as the source area; the corresponding area of ​​the high-heat population area in the planned land boundary area that meets the discontinuous condition and has the smallest average value of stable light intensity is obtained as the target area; The difference between the average stable light intensity of all points on the boundary of the initial clustering area and the boundary to be repaired is recorded as the initial intensity; the difference between the average stable light intensity of all points on the boundary of the associated clustering area and the boundary to be repaired is recorded as the associated intensity; If the initial intensity is greater than the associated intensity, the boundary line of the source area is recorded as the extraction boundary, otherwise the boundary line of the target area is recorded as the extraction boundary; the point with the largest stable light intensity on the extraction boundary is BP, the point with the smallest stable light intensity is SP, and the shortest curve segment passing through BP and SP on the extraction boundary is the extraction curve; The point with the largest stable light intensity on the boundary to be repaired is BP1, the point with the smallest stable light intensity is SP1, and the shortest curve segment passing through BP1 and SP1 on the boundary to be repaired is the curve to be repaired; the curve to be repaired on the boundary to be repaired is deleted; The extracted curve is rotated according to the curve to be repaired and enlarged in equal proportion, and the extracted curve is spliced ​​at the position of the deleted curve to be repaired, and the boundary to be repaired at this time is recorded as the correction boundary.

[0045] The rotation angle is the angle between the straight line passing through BP and SP and the straight line passing through BP1 and SP1.

[0046] Preferably, the method for obtaining the spatial distribution information of the total amount of nighttime light radiation within each planned land area is: By utilizing the spatial mapping relationship between the total amount of night light radiation in the planned land area and the effective buildings in the planned land, the effective buildings in the planned land of each planned land area in the area to be evaluated are distributed to each planned land area.

[0047] Among them, the calculation method of effective buildings in the planned land within the planned land scope is: the effective buildings are the product of the number of buildings in the entire area to be evaluated and the second ratio, wherein the second ratio is: the total number of planned land in the area to be evaluated is N2, the number of planned land in the area to be evaluated whose total amount of night light radiation is greater than the average amount of night light radiation in all planned lands is N1, and the ratio of N1 to N2 is used as the second ratio.

[0048] The embodiment of the present invention provides a system for quickly estimating the spatial distribution of land efficiency, such as Figure 4 The figure shows a structural diagram of a system for rapid estimation of spatial distribution of land efficiency of the present invention. The system for rapid estimation of spatial distribution of land efficiency of this embodiment comprises: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the embodiment of the system for rapid estimation of spatial distribution of land efficiency are implemented.

[0049] The system comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to run in the following units of the system: A remote sensing acquisition unit is used to obtain the temporal remote sensing data of the area to be evaluated and to perform geometric correction on the remote sensing image of the temporal remote sensing data; An image registration unit is used to obtain nighttime light images and population heat maps of the area to be evaluated, and to perform image registration on the nighttime light images, population heat maps and remote sensing images; Boundary annotation unit, used to annotate the planned land boundaries at each time phase in the remote sensing image; A boundary correction unit is used to correct the boundary of the planned land on the night light image according to the population heat map to obtain a corrected boundary; A boundary cutting unit is used to obtain night light data within the planned land area in the area to be evaluated by cutting the corrected night light image of the corresponding area through the corrected boundary; The radiation calculation unit is used to calculate the total amount of night light radiation within the scope of each planned land.

[0050] The system for rapid estimation of spatial distribution of land efficiency can be run in computing devices such as desktop computers, notebooks, PDAs and cloud servers. The system for rapid estimation of spatial distribution of land efficiency can include, but is not limited to, processors and memories. Those skilled in the art can understand that the example is only an example of a system for rapid estimation of spatial distribution of land efficiency, and does not constitute a limitation on a system for rapid estimation of spatial distribution of land efficiency. It can include more or fewer components than the example, or combine certain components, or different components. For example, the system for rapid estimation of spatial distribution of land efficiency can also include input and output devices, network access devices, buses, etc.

[0051] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the operation system of the rapid estimation system for spatial distribution of land efficiency, and uses various interfaces and lines to connect various parts of the entire operation system of the rapid estimation system for spatial distribution of land efficiency.

[0052] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the rapid estimation system of the spatial distribution of land efficiency by running or executing the computer program and / or module stored in the memory and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0053] Although the description of the present invention has been quite detailed and has been described in particular with respect to several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, so as to effectively cover the intended scope of the present invention. In addition, the present invention is described above with the embodiments foreseeable by the inventors, and its purpose is to provide a useful description, and those non-substantial changes to the present invention that are not currently foreseen may still represent equivalent changes of the present invention.

Claims

1. A method for quickly estimating the spatial distribution of land efficiency, characterized in that: The method comprises the following steps: S100, acquiring temporal remote sensing data of the area to be evaluated, and performing geometric correction on the remote sensing image of the temporal remote sensing data; S200, obtaining a night light image and a population heat map of the area to be evaluated, and performing image registration on the night light image, the population heat map and the remote sensing image; S300, marking the planned land boundaries at each time phase in the remote sensing image; S400, performing boundary correction on the planned land boundary on the night light image according to the population heat map to obtain a corrected boundary; S500, obtaining night light data within the planned land area in the area to be evaluated by cutting the corrected night light image of the corresponding area through the corrected boundary; S600, calculating the total amount of nighttime light radiation within each planned land area.

2. The method for rapid estimation of spatial distribution of land efficiency according to claim 1, characterized in that: It also includes a method for obtaining spatial distribution information of the total amount of nighttime light radiation within each planned land area: utilizing the spatial mapping relationship between the total amount of nighttime light radiation in the planned land area and the effective buildings in the planned land, and distributing the effective buildings in the planned land of each planned land area in the area to be evaluated to each planned land area; wherein, a method for calculating the effective buildings in the planned land of the planned land area is: the effective buildings are the product of the number of buildings in the entire area to be evaluated and the second ratio, wherein the second ratio is: let the total number of planned lands in the area to be evaluated be N2, let the number of total amount of nighttime light radiation in the planned lands in the area to be evaluated that is greater than the average value of the total amount of nighttime light radiation in all planned lands be N1, and the ratio of N1 to N2 is taken as the second ratio.

3. The method for rapid estimation of spatial distribution of land efficiency according to claim 1, characterized in that: In S400, the method for performing boundary correction on the planned land boundary on the night light image according to the population heat map to obtain the corrected boundary includes: performing edge detection on the grayscale population heat map to obtain a region composed of multiple edge lines, recording the average grayscale value of all pixels in each region as the contrast grayscale, and recording the region in each region where the average grayscale value is greater than the contrast grayscale as a population high heat area; according to the acquisition time of the night light image, judging the population heat maps collected at the corresponding time of each night light image in sequence: if a population high heat area that does not appear at the corresponding position of the population heat map collected last time appears in each planned land boundary area of ​​the current population heat map, the position of the population high heat area is recorded as a population cluster area; The population heat map corresponding to the population cluster area is used as the initial cluster area of ​​the current planned land boundary area, and the point with the largest gray value in the population cluster area is used as the mark point; if there is a high-heat population area other than the population cluster area on the population heat map collected last time in the initial cluster area, then the point with the largest gray value in the high-heat population area other than the population cluster area on the population heat map collected last time and the point with the largest distance from the mark point is used as the anchor point; the high-heat population area where the anchor point is located is recorded as the associated cluster area; The average gray value of each point on the edge line of the initial cluster area is A1; the average gray value of each point on the edge line of the associated cluster area is A2; the point closest to the edge line of the associated cluster area among the points on the edge line of the initial cluster area with a gray value greater than A1 is taken as the anchor point, and the point closest to the edge line of the initial cluster area among the points on the edge line of the associated cluster area with a gray value greater than A2 is taken as the calibration point; the straight line passing through the anchor point and the anchor point is L1; the straight line passing through the calibration point and the calibration point is L2; ​​the area between L1 and L2 on the population heat map is the population change scanning area of ​​the boundary area of ​​the current planned land use; In each planned land boundary area, if there is a population hotspot in the population change scanning area passing through the planned land boundary area that meets the discontinuous duration condition, the planned land boundary of the planned land boundary area is marked as a boundary to be repaired; boundary correction is performed on the boundary to be repaired to obtain a corrected boundary.

4. The method for rapid estimation of spatial distribution of land efficiency according to claim 3, characterized in that: The discontinuous duration condition is: in the population change scanning area, if the average value of the stable light intensity in the corresponding area of ​​the night light image collected at the corresponding time of the current population hot zone is less than the average value of the stable light intensity in the corresponding area of ​​the night light image in the initial gathering area in the planned land boundary area, then the current population hot zone is marked as meeting the discontinuous condition.

5. The method for rapid estimation of spatial distribution of land efficiency according to claim 3, characterized in that: Replace the discontinuous condition with: the time when the current population high-heat area first appears is recorded as the start time ST; in the population change scanning area, the time between the first appearance of the initial gathering area in the planned land boundary area and the start time ST of the current population high-heat area is the radiation start time; The time from the moment after the start-up duration ends to the moment when the average grayscale value of all points on the edge line of the current population high-heat area is first greater than the contrast grayscale or A1 is the radiation reduction duration; if the radiation reduction duration is less than the radiation start-up duration, the average value of the stable light intensity in the corresponding area of ​​the night light image collected at the corresponding moment of the current population high-heat area is less than the average value of the stable light intensity in the corresponding area of ​​the initial gathering area in the said night light image, then the current population high-heat area is marked as meeting the discontinuous condition.

6. The method for rapid estimation of spatial distribution of land efficiency according to claim 3, characterized in that: In S400, the method of performing boundary correction on the boundary to be repaired to obtain the corrected boundary is: The point with the largest stable light intensity in the corresponding area of ​​the high-heat population zone that meets the discontinuous condition in the boundary area of ​​the planned land is P1, and the point with the smallest stable light intensity is P2; the point with the smallest difference in stable light intensity with P1 on the boundary to be repaired is P3, and the point with the smallest difference in stable light intensity with P2 on the boundary to be repaired is P4; the shortest curve segment passing through P3 and P4 on the boundary to be repaired is the repair curve; the extracted curve passing through P1 and P2 on the boundary of the corresponding area of ​​the high-heat population zone that meets the discontinuous condition in the boundary area of ​​the planned land is used; the repair curve on the boundary to be repaired is deleted; the extracted curve is rotated according to the repair curve and enlarged proportionally, the extracted curve is spliced ​​at the position of the deleted repair curve, and the boundary to be repaired at this time is recorded as the corrected boundary.

7. The method for rapid estimation of spatial distribution of land efficiency according to claim 6, characterized in that: In S400, the method of performing boundary correction on the boundary to be repaired to obtain the corrected boundary is replaced by: The corresponding area of ​​the population high-heat area with the largest average stable light intensity among the corresponding areas of the population high-heat area that meets the discontinuous condition in the boundary area of ​​the planned land is obtained as the source area; the corresponding area of ​​the population high-heat area with the smallest average stable light intensity among the corresponding areas of the population high-heat area that meets the discontinuous condition in the boundary area of ​​the planned land is obtained as the target area; the difference between the average stable light intensity of all points on the boundary of the initial gathering area and the boundary to be repaired is recorded as the initial intensity; the difference between the average stable light intensity of all points on the boundary of the associated gathering area and the boundary to be repaired is recorded as the associated intensity; if the initial intensity is greater than the associated intensity, the boundary line of the source area is recorded as the extraction boundary, otherwise the boundary line of the target area is recorded as the extraction boundary; the point with the largest stable light intensity on the extraction boundary is BP, the point with the smallest stable light intensity is SP, and the shortest curve segment on the extraction boundary passing through BP and SP is recorded as the extraction curve; The point with the largest stable light intensity on the boundary to be repaired is BP1, the point with the smallest stable light intensity is SP1, and the shortest curve segment passing through BP1 and SP1 on the boundary to be repaired is the curve to be repaired; the curve to be repaired on the boundary to be repaired is deleted; The extracted curve is rotated according to the curve to be repaired and enlarged in equal proportion, and the extracted curve is spliced ​​at the position of the deleted curve to be repaired, and the boundary to be repaired at this time is recorded as the correction boundary.

8. A rapid estimation system for spatial distribution of land efficiency, characterized in that: The system for rapid estimation of the spatial distribution of land efficiency comprises: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of any one of the methods for rapid estimation of the spatial distribution of land efficiency in claims 1-7 are implemented.

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