A rapid method for estimating the spatial distribution of land efficiency

Abstract

This invention discloses a rapid method and system for estimating the spatial distribution of land efficiency, applied in the field of spatial geographic information data processing technology. It involves acquiring temporal remote sensing data of the area to be evaluated, performing geometric correction on the remote sensing images of the temporal remote sensing data, obtaining corrected boundaries by correcting the planned land boundaries on nighttime light imagery based on population heat maps, cutting the corrected nighttime light imagery of the corresponding area using the corrected boundaries, calculating the total nighttime light radiation within each planned land area, and improving the accuracy of the estimation by accurately correcting the area distortion of the evaluation area caused by the low data acquisition frequency of the stable nighttime light imagery dataset using a high-sampling-rate population heat map. This improvement enhances the smoothness of the stable light irradiance boundary, thereby improving the speed and accuracy of land estimation.

Description

Technical Field

[0001] This invention relates to the field of spatial geographic information data processing technology, specifically to a rapid estimation method for the spatial distribution of land efficiency. Background Technology

[0002] Currently, there are two main traditional methods for measuring land efficiency: The first method is based on administrative units at all levels, combining non-agricultural GDP statistics and planned land use statistics to calculate the planned land output efficiency of each administrative unit. However, this method cannot reflect the efficiency distribution within administrative units, and the difficulty in collecting statistical data for administrative units below the county level limits in-depth research on the spatial distribution of planned land use efficiency in these small-scale areas. The second method uses specific plots as units, obtaining planned land use efficiency through field surveys. While this method can provide more accurate data, it is labor-intensive and unsuitable for large-scale dynamic studies. Furthermore, differences in survey standards and participant responsiveness can affect the accuracy of GDP data. Therefore, there is an urgent need to utilize new spatial information technologies to rationally allocate regional statistical non-agricultural GDP data to smaller spatial units, enabling rapid estimation of the spatial distribution of regional planned land use efficiency.

[0003] Therefore, to efficiently and quickly estimate the spatial distribution of land efficiency, a method for rapidly estimating the spatial distribution of planned land use efficiency, as provided in Chinese invention patent CN106156756B, utilizes TM imagery data and DMSP / OLS nighttime light data to obtain spatial distribution information of planned land use and total nighttime light radiation in the area to be evaluated. By leveraging the spatial mapping relationship between total nighttime light radiation and non-agricultural GDP, the statistical value of non-agricultural GDP in the area to be evaluated is distributed across small spatial units, thereby quickly estimating the spatial distribution of planned land use efficiency in the region. Combining TM remote sensing imagery data with nighttime light data overcomes the drawback of overestimating light area caused by the spillover effect of nighttime light data. Compared with previous methods, it has significant advantages in estimation speed, accuracy, and method universality. However, in the actual processing of spatial geographic information, there are many problems such as discontinuity and oversaturation in the planning area at night due to the low data acquisition frequency of stable nighttime light image datasets. If the light area is estimated solely based on the spillover effect of nighttime light data, especially at the boundary of the planning area, the actual impact range of stable nighttime light will be distorted, thus reducing the accuracy of estimating the actual irradiance impact range of stable nighttime light. Summary of the Invention

[0004] The purpose of this invention is to propose a rapid estimation method and system for the spatial distribution of land efficiency, in order to solve one or more technical problems existing in the prior art, and at least provide a beneficial option or create conditions.

[0005] To achieve the above objectives, according to one aspect of the present invention, a rapid method for estimating the spatial distribution of land efficiency is provided, the method comprising the following steps:

[0006] S100: Acquire temporal remote sensing data of the area to be evaluated, and perform geometric correction on the remote sensing images of the temporal remote sensing data;

[0007] S200: Acquire nighttime light images and population heat maps of the area to be evaluated, and perform image registration between the nighttime light images, population heat maps, and remote sensing images;

[0008] S300 marks the planned land boundaries in remote sensing images at various time phases;

[0009] S400, based on the population heat map, performs boundary correction on the planned land boundary in the nighttime light image to obtain the corrected boundary;

[0010] S500 obtains nighttime light data within the planned land area of ​​the region to be evaluated by correcting the nighttime light images of the corresponding areas through boundary cutting.

[0011] S600 calculates the total nighttime light radiation within each planned land area.

[0012] Furthermore, in S400, the population heat map can be any one of the following: mobile phone signal population heat map, WeChat YiChuxing population heat map, Baidu Map population heat map, or Baidu Huiyan data population heat map.

[0013] The method for image registration is to use remote sensing images as reference images, construct the correspondence between the reference images and geographic coordinates, and register the nighttime light images, population heat maps and reference images respectively.

[0014] Among them, the nighttime light images are from the DMSP / OLS stable nighttime light image dataset.

[0015] The calculation method for the total nighttime light radiation within the planned land area is as follows: the total nighttime 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 portion of the nighttime light image of each spatial unit within the planned land area.

[0016] The spatial unit is a tetrahedral or hexahedral unit divided by grid division or fishing net division method.

[0017] It also includes obtaining spatial distribution information on the total nighttime light radiation within each planned land area.

[0018] The method for obtaining the spatial distribution information of the total nighttime light radiation within each planned land area is as follows: by utilizing the spatial mapping relationship between the total nighttime light radiation within the planned land area and the non-agricultural GDP statistics, the non-agricultural GDP statistics of each planned land area in the area to be evaluated are distributed onto each planned land area.

[0019] The calculation method for the non-agricultural GDP statistics within the planned land area is as follows: the non-agricultural GDP statistics are the product of the non-agricultural GDP statistics of the entire area to be evaluated and the first ratio; wherein, the first ratio is the ratio of the total nighttime light radiation within the planned land area to the total nighttime light radiation within the planned land area of ​​the entire area to be evaluated.

[0020] Preferably, the spatial distribution information of total nighttime light radiation is obtained according to the spatial distribution information method of the total nighttime light radiation in the rapid estimation method of spatial distribution of planned land use efficiency provided by Chinese invention patent CN106156756B.

[0021] Preferably, the method for obtaining the spatial distribution information of total nighttime light radiation within each planned land area is as follows:

[0022] By utilizing the spatial mapping relationship between the total nighttime light radiation within the planned land area and the effective buildings within the planned land area, the effective buildings within each planned land area in the area to be evaluated are distributed across each planned land area.

[0023] The calculation method for effective buildings in the planned land area is as follows: the effective buildings are the product of the number of buildings in the entire area to be evaluated and the second ratio. The second ratio is as follows: let N2 be the total number of planned land in the area to be evaluated, and let N1 be the number of planned land in the area to be evaluated whose total nighttime light radiation is greater than the average of the total nighttime light radiation of all planned land. The ratio of N1 to N2 is then used as the second ratio.

[0024] Existing land efficiency assessment methods based on nighttime light imagery typically rely directly or indirectly on the range of nighttime light illumination to determine land planning efficiency. However, due to the uneven distribution of light in specific areas or its underutilization due to spatiotemporal relationships, this phenomenon can lead to misjudgments of nighttime light intensity, resulting in overestimation or underestimation of the actual brightness in certain areas. Furthermore, the low data acquisition frequency (101-minute period) of stable nighttime light imagery datasets causes discontinuities and oversaturation issues in rapidly changing nighttime urban areas over time periods. (For example, the difference between high-brightness periods and low-brightness sleep periods in residential areas can cause significant discontinuities and oversaturation issues; see reference: Zhang Mengqi et al. Correction method for DMSP / OLS stable nighttime light imagery [J]. Surveying and Mapping Bulletin, 2017(12):6.DOI:10.13474 / j.cnki.11-2246.2017.0379), these factors make it impossible to reflect the impact of stable nighttime light on the irradiance range of land use in a timely and accurate manner. Since the population heat map is updated every 5-15 minutes and is a population density distribution map obtained by statistical analysis of mobile phone user location information, the population heat map will not affect the population gathering area during the nighttime rest period. Therefore, this application uses the population heat map, which has a faster update frequency and is not easily affected, to correct the irradiance impact range of the planned land boundary in the nighttime light image, specifically:

[0025] Furthermore, in S400, the method for obtaining the corrected boundary by correcting the planned land use boundary on the nighttime light image based on the population heat map includes:

[0026] Edge detection is performed on the grayscale population heatmap to obtain regions composed of multiple edge lines. The average grayscale value of all pixels in each region is recorded as the contrast grayscale. Regions with an average grayscale value greater than the contrast grayscale value are recorded as high-population areas. (Since areas with relatively large populations appear reddish on the population heatmap and brighter after grayscale conversion, these areas are considered high-population areas.)

[0027] Based on the acquisition time of the nighttime light images, the population heat maps collected at the corresponding times of each nighttime light image are judged in sequence: if a high population heat area appears in the planning land boundary area of ​​the current population heat map that did not appear in the corresponding location of the previous population heat map, the location of the high population heat area is recorded as a population cluster area.

[0028] The population heat map corresponding to the population cluster area is used as the initial cluster area of ​​the current planned land boundary area (i.e., the area where local population clusters are first detected in the current planned land boundary area), and the point with the largest gray value in the population cluster area is used as the marker.

[0029] If there are high-population areas other than population clusters on the population heat map collected in the previous collection of the initial cluster area, then the point with the largest gray value among the high-population areas other than population clusters on the previous collection of the population heat map, which is the point with the largest distance from the marker, is the anchor point; the high-population area where the anchor point is located is called the associated cluster area.

[0030] The average gray value of each point on the edge of the initial clustering region is A1; the average gray value of each point on the edge of the associated clustering region is A2.

[0031] Anchor points are selected from the points on the edge of the initial cluster area whose gray values ​​are greater than A1 and are closest to the edge of the associated cluster area. Calibration points are selected from the points on the edge of the associated cluster area whose gray values ​​are greater than A2 and are closest to the edge of the initial cluster area. The straight line between the anchor point and the anchor point is designated L1; the straight line between the calibrator point and the calibrator point is designated L2; the area between L1 and L2 on the population heat map is designated as the population change scanning area of ​​the current planned land boundary. (Because the population heat map updates frequently, it introduces significant algorithmic complexity to real-time scanning. In actual scanning, full scanning is slow. To accelerate the population change scanning speed in subsequent steps, a population change scanning area with the most obvious population change characteristics, consisting of points on the edges of two significantly correlated regions with similar changes, is needed to reduce algorithmic complexity and thus accelerate the scanning speed.)

[0032] In each planned land boundary area, if a high-population hotspot exists in the population change scanning area passing through the planned land boundary area and meets the discontinuous duration condition, then 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 the corrected boundary.

[0033] Specifically, the discontinuous duration condition is as follows: Within the population change scanning area, if the average stable light intensity in the corresponding area of ​​the nighttime light image collected at the current high-population area is less than the average stable light intensity in the corresponding area of ​​the nighttime light image of the initial cluster area within the planned land boundary area, then the current high-population area is marked as meeting the discontinuity condition. (That is, within the current population change scanning area, meeting the discontinuity condition means that the stable light intensity changes abnormally. This is obviously caused by the relatively low data acquisition frequency of the stable nighttime light image dataset, the discontinuity and oversaturation caused by the time-span changes of the rapidly changing nighttime urban area, and therefore the corresponding planned land boundary is affected.)

[0034] While the above methods can quickly scan the boundaries of most stable nighttime light intensity changes and anomalous irradiance effects, they still suffer from scan saturation issues when these effects disappear rapidly in high-population areas (the rate of disappearance is less than the initial appearance interval in population change scanning areas). This is particularly problematic at planned land boundaries, where the actual impact range of stable nighttime light intensity can be distorted, resulting in the inability to scan the actual temporal impact range of stable light irradiance during certain time periods. To address this issue, this application proposes the following solution:

[0035] Preferably, the discontinuous duration condition is as follows: the time when the current high-population hot zone first appears (i.e., the time when the population heat map is collected when the high-population hot zone first appears on the population heat map) is the start time ST; in the population change scanning area, the duration between the time when the initial agglomeration area first appears in the planned land boundary area and the start time ST of the current high-population hot zone is the radiation start duration; the duration between the time when the start duration ends and the time when the average gray value of all points on the edge line of the current high-population hot zone first exceeds the contrast gray value or A1 is the radiation decrease duration; if the radiation decrease duration is less than the radiation start duration, and the average stable light intensity in the corresponding area of ​​the night light image collected at the corresponding time of the current high-population hot zone is less than the average stable light intensity in the corresponding area of ​​the night light image of the initial agglomeration area, then the current high-population hot zone is marked as satisfying the discontinuous condition. (That is, within the current population change scanning area, when the duration of radiation reduction is shorter than the duration of radiation activation, a sudden and short duration of light radiation occurs. This clearly indicates a significant and unreasonable change in the light irradiance range at the geographical location corresponding to the population concentration area. Since the population heat map is updated every 5-15 minutes and is a population density distribution map obtained through statistical analysis of mobile phone user location information, the population heat map will not affect the population concentration area during the nighttime rest period. The above discontinuous condition is used to identify the boundary of the light irradiance range affected by changes in the light irradiance range due to the low data acquisition frequency of the nighttime light image dataset, even though the population concentration area has not changed significantly. Therefore, this discontinuous condition indicates that the stable light intensity has changed abnormally, thus affecting the accuracy of the planned land boundary and failing to reflect the land use range affected by the range assessment of the light irradiance impact in a timely manner. Therefore, judging the discontinuous duration condition can accurately identify the distortion boundary affected by the low data acquisition frequency of the nighttime light image dataset on the range of light irradiance impact.)

[0036] In S400, the method for obtaining the corrected boundary by boundary correction of the boundary to be repaired is as follows:

[0037] In the planning land boundary area, the point with the highest stable light intensity in the corresponding area of ​​the high-population hot zone that meets the discontinuous condition is designated as P1, and the point with the lowest stable light intensity is designated as P2. The point on the boundary to be repaired with the smallest difference in stable light intensity between P1 and P3 is designated as P3, and the point on the boundary to be repaired with the smallest difference in stable light intensity between P2 and P4 is designated as P4. The shortest curve segment on the boundary to be repaired between P3 and P4 is designated as the repair curve. The extracted curve is then used on the boundary of the high-population hot zone that meets the discontinuous condition in the planning land boundary area, passing between P1 and P2. 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 then stitched onto the deleted repair curve. The boundary to be repaired at this point is designated as the corrected boundary.

[0038] The angle of rotation is the angle between the line passing through P1 and P2 and the line passing through P3 and P4.

[0039] Using the methods described above, the stable light intensity characteristics of high-population-area areas within the planned land boundary region that meet the discontinuous condition were utilized. Based on the characteristics of irradiance from high to low, the boundary curve segments with significant differences in stable light intensity on the repair boundary were adjusted. This process effectively corrected the distortion of the assessed area caused by erroneous light irradiance due to low data acquisition frequency, thereby improving the accuracy of the estimation. Furthermore, the preferred correction method, by screening the average stable light intensity of the initial and associated cluster boundaries, identified areas corresponding to high-population-area areas that are closer to the boundary to be repaired, further improving the smoothness of the boundary to be repaired affected by stable light irradiance.

[0040] Preferably, in S400, the method for obtaining the corrected boundary by boundary correction of the boundary to be repaired is as follows:

[0041] The region corresponding to the high-population-heated area with the largest average stable light intensity among the corresponding regions of the high-population-heated area that meets the discontinuous condition in the planned land boundary area is the source region; the region corresponding to the high-population-heated area with the smallest average stable light intensity among the corresponding regions of the high-population-heated area that meets the discontinuous condition in the planned land boundary area is the target region.

[0042] The initial intensity is defined as 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; the associated intensity is defined as 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.

[0043] If the initial intensity is greater than the associated intensity, the boundary line of the source region is recorded as the extraction boundary; otherwise, the boundary line of the target region is recorded as the extraction boundary. The point with the largest stable light intensity on the extraction boundary is BP, and the point with the smallest stable light intensity is SP. The shortest curve segment between BP and SP on the extraction boundary is used as the extraction curve.

[0044] The point with the highest stable light intensity on the boundary to be repaired is designated as BP1, and the point with the lowest stable light intensity is designated as SP1. The shortest curve segment on the boundary to be repaired between BP1 and SP1 is designated as the curve to be repaired. The curve to be repaired on the boundary to be repaired is then deleted.

[0045] The extracted curve is rotated and enlarged proportionally according to the curve to be repaired. The extracted curve is then stitched onto the deleted curve to be repaired. The boundary to be repaired at this point is recorded as the correction boundary.

[0046] The angle of rotation is the angle between the line passing through BP and SP and the line passing through BP1 and SP1.

[0047] The present invention also provides a rapid estimation system for 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 a unit of the following system:

[0048] The remote sensing acquisition unit is used to acquire temporal remote sensing data of the area to be evaluated and to perform geometric correction on the remote sensing images of the temporal remote sensing data.

[0049] The image registration unit is used to acquire nighttime light images and population heat maps of the area to be evaluated, and to perform image registration between the nighttime light images, population heat maps and remote sensing images;

[0050] Boundary labeling units are used to label the planned land boundaries in remote sensing images at various time phases;

[0051] The boundary correction unit is used to correct the boundaries of planned land use on nighttime light images based on the population heat map to obtain the corrected boundaries;

[0052] The boundary cutting unit is used to obtain nighttime light data within the planned land area of ​​the area to be evaluated by correcting the nighttime light image of the corresponding area by cutting the boundary.

[0053] The radiation calculation unit is used to calculate the total nighttime light radiation within each planned land area.

[0054] The beneficial effects of this invention are as follows: This invention provides a rapid estimation method and system for the spatial distribution of land efficiency. It addresses the discontinuity and oversaturation problems caused by the low data acquisition frequency of stable nighttime light image datasets, which lead to distortion in the estimation of light area. It can promptly reflect the land use range affected by the assessment of the range of light irradiance, accurately redetermine the boundary of the range of light irradiance, ensure the actual accuracy of the range of light irradiance, and improve the land estimation speed by reducing algorithm complexity and accelerating the scanning speed. Attached Figure Description

[0055] The above and other features of the present invention will become more apparent from the detailed description of the embodiments shown in conjunction with the accompanying drawings. In the accompanying drawings, the same reference numerals denote the same or similar elements. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort. In the drawings:

[0056] Figure 1 The diagram shows a flowchart of a rapid method for estimating the spatial distribution of land efficiency.

[0057] Figure 2 The image shown is a population heatmap of a certain area after being converted to grayscale.

[0058] Figure 3 The image shown is a nighttime light display of a certain location.

[0059] Figure 4 The diagram shows the structure of a rapid estimation system for the spatial distribution of land efficiency. Detailed Implementation

[0060] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution, and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0061] Example 1

[0062] like Figure 1 The diagram shows a flowchart of a rapid estimation method for the spatial distribution of land efficiency according to the present invention. The following is a summary of the method. Figure 1 This paper describes a rapid method for estimating the spatial distribution of land efficiency according to an embodiment of the present invention.

[0063] This invention proposes a rapid method for estimating the spatial distribution of land efficiency, specifically including the following steps:

[0064] S100: Acquire temporal remote sensing data of the area to be evaluated, and perform geometric correction on the remote sensing images of the temporal remote sensing data;

[0065] S200: Acquire nighttime light images and population heat maps of the area to be evaluated, and perform image registration between the nighttime light images, population heat maps, and remote sensing images;

[0066] S300 marks the planned land boundaries in remote sensing images at various time phases;

[0067] S400, based on the population heat map, performs boundary correction on the planned land boundary in the nighttime light image to obtain the corrected boundary;

[0068] S500 obtains nighttime light data within the planned land area of ​​the region to be evaluated by correcting the nighttime light images of the corresponding areas through boundary cutting.

[0069] S600 calculates the total nighttime light radiation within each planned land area.

[0070] Furthermore, in S400, the population heat map is a mobile phone signal population heat map.

[0071] The method for image registration is to use remote sensing images as reference images, construct the correspondence between the reference images and geographic coordinates, and register the nighttime light images, population heat maps and reference images respectively.

[0072] Among them, the nighttime light images are from the DMSP / OLS stable nighttime light image dataset.

[0073] The calculation method for the total nighttime light radiation within the planned land area is as follows: the total nighttime 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 portion of the nighttime light image of each spatial unit within the planned land area.

[0074] The spatial unit is a tetrahedral unit divided by a grid.

[0075] It also includes obtaining spatial distribution information on the total nighttime light radiation within each planned land area.

[0076] The method for obtaining the spatial distribution information of the total nighttime light radiation within each planned land area is as follows: by utilizing the spatial mapping relationship between the total nighttime light radiation within the planned land area and the non-agricultural GDP statistics, the non-agricultural GDP statistics of each planned land area in the area to be evaluated are distributed onto each planned land area.

[0077] The calculation method for the non-agricultural GDP statistics within the planned land area is as follows: the non-agricultural GDP statistics are the product of the non-agricultural GDP statistics of the entire area to be evaluated and the first ratio; wherein, the first ratio is the ratio of the total nighttime light radiation within the planned land area to the total nighttime light radiation within the planned land area of ​​the entire area to be evaluated.

[0078] Preferably, the spatial distribution information of total nighttime light radiation is obtained according to the spatial distribution information method of the total nighttime light radiation in the rapid estimation method of spatial distribution of planned land use efficiency provided by Chinese invention patent CN106156756B.

[0079] Furthermore, in S400, the method for obtaining the corrected boundary by correcting the planned land use boundary on the nighttime light image based on the population heat map includes:

[0080] like Figure 2 The image shows a population heatmap after grayscale conversion. Edge detection is performed on the grayscale population heatmap to obtain regions composed of multiple edge lines. The average grayscale value of all pixels in each region is recorded as the contrast grayscale. Regions with an average grayscale value greater than the contrast grayscale are recorded as high-population heatmaps.

[0081] like Figure 3 The image shown is a nighttime light image. Based on the acquisition time of the nighttime light images, the population heat map collected at the corresponding time of each nighttime light image is judged in sequence: if a high population heat area appears in the planning land boundary area of ​​the current population heat map that did not appear in the corresponding position of the previous population heat map, the location of the high population heat area is recorded as a population cluster area.

[0082] The population heat map corresponding to the population cluster 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 is used as the marker.

[0083] If there are high-population areas other than population clusters on the population heat map collected in the previous collection of the initial cluster area, then the point with the largest gray value among the high-population areas other than population clusters on the previous collection of the population heat map, which is the point with the largest distance from the marker, is the anchor point; the high-population area where the anchor point is located is called the associated cluster area.

[0084] The average gray value of each point on the edge of the initial clustering region is A1; the average gray value of each point on the edge of the associated clustering region is A2.

[0085] Anchor points are selected from those points on the edge line of the initial cluster area whose gray values ​​are greater than A1 and are closest to the edge line of the associated cluster area. Calibration points are selected from those points on the edge line of the associated cluster area whose gray values ​​are greater than A2 and are closest to the edge line of the initial cluster area. The straight line between the anchor point and the anchor point is designated as L1. The straight line between the calibration point and the calibration point is designated as L2. The area between L1 and L2 on the population heat map is designated as the population change scanning area of ​​the current planned land boundary area.

[0086] In each planned land boundary area, if a high-population hotspot exists in the population change scanning area passing through the planned land boundary area and meets the discontinuous duration condition, then 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 the corrected boundary.

[0087] Specifically, the discontinuous duration condition is as follows: In the population change scanning area, if the average stable light intensity in the corresponding area of ​​the nighttime light image collected at the corresponding time of the current high-population area is less than the average stable light intensity in the corresponding area of ​​the nighttime light image of the initial cluster area in the planned land boundary area, then the current high-population area is marked as meeting the discontinuous condition.

[0088] In S400, the method for obtaining the corrected boundary by boundary correction of the boundary to be repaired is as follows:

[0089] In the planning land boundary area, the point with the highest stable light intensity in the corresponding area of ​​the high-population hot zone that meets the discontinuous condition is designated as P1, and the point with the lowest stable light intensity is designated as P2. The point on the boundary to be repaired with the smallest difference in stable light intensity between P1 and P3 is designated as P3, and the point on the boundary to be repaired with the smallest difference in stable light intensity between P2 and P4 is designated as P4. The shortest curve segment on the boundary to be repaired between P3 and P4 is designated as the repair curve. The extracted curve is then used on the boundary of the high-population hot zone that meets the discontinuous condition in the planning land boundary area, passing between P1 and P2. 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 then stitched onto the deleted repair curve. The boundary to be repaired at this point is designated as the corrected boundary.

[0090] The angle of rotation is the angle between the line passing through P1 and P2 and the line passing through P3 and P4.

[0091] Example 2

[0092] This embodiment 2 is based on embodiment 1, but the following method is replaced:

[0093] Preferably, the discontinuous duration condition is as follows: the time when the current high-population hot zone first appears (i.e., the time when the population heat map is collected when the high-population hot zone first appears on the population heat map) is the start time ST; in the population change scanning area, the duration between the time when the initial agglomeration area first appears in the planned land boundary area and the start time ST of the current high-population hot zone is the radiation start duration; the duration between the time when the start duration ends and the time when the average gray value of all points on the edge line of the current high-population hot zone first exceeds the contrast gray value or A1 is the radiation decrease duration; if the radiation decrease duration is less than the radiation start duration, and the average stable light intensity in the corresponding area of ​​the night light image collected at the corresponding time of the current high-population hot zone is less than the average stable light intensity in the corresponding area of ​​the night light image of the initial agglomeration area, then the current high-population hot zone is marked as satisfying the discontinuous condition.

[0094] Preferably, in S400, the method for obtaining the corrected boundary by boundary correction of the boundary to be repaired is as follows:

[0095] The region corresponding to the high-population-heated area with the largest average stable light intensity among the corresponding regions of the high-population-heated area that meets the discontinuous condition in the planned land boundary area is the source region; the region corresponding to the high-population-heated area with the smallest average stable light intensity among the corresponding regions of the high-population-heated area that meets the discontinuous condition in the planned land boundary area is the target region.

[0096] The initial intensity is defined as 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; the associated intensity is defined as 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.

[0097] If the initial intensity is greater than the associated intensity, the boundary line of the source region is recorded as the extraction boundary; otherwise, the boundary line of the target region is recorded as the extraction boundary. The point with the largest stable light intensity on the extraction boundary is BP, and the point with the smallest stable light intensity is SP. The shortest curve segment between BP and SP on the extraction boundary is used as the extraction curve.

[0098] The point with the highest stable light intensity on the boundary to be repaired is designated as BP1, and the point with the lowest stable light intensity is designated as SP1. The shortest curve segment on the boundary to be repaired between BP1 and SP1 is designated as the curve to be repaired. The curve to be repaired on the boundary to be repaired is then deleted.

[0099] The extracted curve is rotated and enlarged proportionally according to the curve to be repaired. The extracted curve is then stitched onto the deleted curve to be repaired. The boundary to be repaired at this point is recorded as the correction boundary.

[0100] The angle of rotation is the angle between the line passing through BP and SP and the line passing through BP1 and SP1.

[0101] Preferably, the method for obtaining the spatial distribution information of total nighttime light radiation within each planned land area is as follows:

[0102] By utilizing the spatial mapping relationship between the total nighttime light radiation within the planned land area and the effective buildings within the planned land area, the effective buildings within each planned land area in the area to be evaluated are distributed across each planned land area.

[0103] The calculation method for effective buildings in the planned land area is as follows: the effective buildings are the product of the number of buildings in the entire area to be evaluated and the second ratio. The second ratio is as follows: let N2 be the total number of planned land in the area to be evaluated, and let N1 be the number of planned land in the area to be evaluated whose total nighttime light radiation is greater than the average of the total nighttime light radiation of all planned land. The ratio of N1 to N2 is then used as the second ratio.

[0104] An embodiment of the present invention provides a rapid estimation system for the spatial distribution of land efficiency, such as... Figure 4 The diagram shows a structure of a rapid estimation system for the spatial distribution of land efficiency according to the present invention. This embodiment of the rapid estimation system for the spatial distribution of land efficiency includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps in the above embodiment of the rapid estimation system for the spatial distribution of land efficiency.

[0105] The system includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program in units of the following system:

[0106] The remote sensing acquisition unit is used to acquire temporal remote sensing data of the area to be evaluated and to perform geometric correction on the remote sensing images of the temporal remote sensing data.

[0107] The image registration unit is used to acquire nighttime light images and population heat maps of the area to be evaluated, and to perform image registration between the nighttime light images, population heat maps and remote sensing images;

[0108] Boundary labeling units are used to label the planned land boundaries in remote sensing images at various time phases;

[0109] The boundary correction unit is used to correct the boundaries of planned land use on nighttime light images based on the population heat map to obtain the corrected boundaries;

[0110] The boundary cutting unit is used to obtain nighttime light data within the planned land area of ​​the area to be evaluated by correcting the nighttime light image of the corresponding area by cutting the boundary.

[0111] The radiation calculation unit is used to calculate the total nighttime light radiation within each planned land area.

[0112] The aforementioned rapid estimation system for the spatial distribution of land efficiency can run on computing devices such as desktop computers, laptops, handheld computers, and cloud servers. The system that can run on this rapid estimation system for the spatial distribution of land efficiency may include, but is not limited to, processors and memory. Those skilled in the art will understand that the examples described are merely illustrations of a rapid estimation system for the spatial distribution of land efficiency and do not constitute a limitation on such a system. It may include more or fewer components, or a combination of certain components, or different components. For example, the rapid estimation system for the spatial distribution of land efficiency may also include input / output devices, network access devices, buses, etc.

[0113] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor. This processor is the control center of the rapid land efficiency spatial distribution estimation system, connecting various parts of the system through various interfaces and lines.

[0114] The memory can be used to store the computer program and / or modules. The processor, by running or executing the computer program and / or modules stored in the memory and calling the data stored in the memory, realizes various functions of the rapid estimation system for the spatial distribution of land efficiency. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created based on the use of the mobile phone (such as audio data, phonebook, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0115] Although the invention has been described in considerable detail and particularly with regard to several of the described embodiments, it is not intended to limit itself to any of these details or embodiments or any particular embodiment, thereby effectively covering the intended scope of the invention. Furthermore, the invention has been described above with respect to embodiments foreseeable by the inventors in order to provide a useful description, and non-substantial modifications to the invention that have not yet been foreseen may still represent equivalent modifications.

Claims

1. A rapid method for estimating the spatial distribution of land efficiency, characterized in that, The method includes the following steps: S100: Acquire temporal remote sensing data of the area to be evaluated, and perform geometric correction on the remote sensing images of the temporal remote sensing data; S200: Acquire nighttime light images and population heat maps of the area to be evaluated, and perform image registration between the nighttime light images, population heat maps, and remote sensing images; S300 marks the planned land boundaries in remote sensing images at various time phases; S400, based on the population heat map, performs boundary correction on the planned land boundary in the nighttime light image to obtain the corrected boundary; S500 obtains nighttime light data within the planned land area of ​​the region to be evaluated by correcting the nighttime light images of the corresponding areas through boundary cutting. S600, calculates the total nighttime light radiation within each planned land area; In S400, the method for obtaining the corrected boundary by correcting the planned land boundary on the nighttime light image based on the population heat map includes: performing edge detection on the grayscale population heat map to obtain regions composed of multiple edge lines, recording the average gray value of all pixels in each region as the contrast gray value, and recording the regions in each region with an average gray value greater than the contrast gray value as high-population areas; according to the acquisition time of the nighttime light images, judging the population heat maps collected at the corresponding time of each nighttime light image in sequence: if a high-population area that did not appear at the corresponding position in the previous population heat map appears in the planned land boundary region of the current population heat map, the location of the high-population area is recorded as a population cluster area; The population heat map corresponding to the population cluster is taken as the initial cluster area of ​​the current planned land boundary area, and the point with the largest gray value in the population cluster is taken as the marker. If there are high-population heat areas other than the population cluster in the previous population heat map of the initial cluster area, then the point with the largest gray value among the points with the largest distance from the marker in the high-population heat areas other than the population cluster in the previous population heat map is taken as the anchor point. The high-population heat area where the anchor point is located is called the associated cluster area. The average gray value of each point on the edge of the initial cluster area is A1; the average gray value of each point on the edge of the associated cluster area is A2; the point closest to the edge of the associated cluster area among the points on the edge of the initial cluster area with a gray value greater than A1 is taken as the anchor point; the point closest to the edge of the initial cluster area among the points on the edge of the associated cluster area with a gray value greater than A2 is taken as the calibration point; the straight line between the anchor point and the anchor point is L1; the straight line between 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 current planned land boundary area. In each planned land boundary area, if a high-population hotspot exists in the population change scanning area passing through the planned land boundary area and meets the discontinuous duration condition, then 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 the corrected boundary.

2. The method for rapidly estimating the 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 nighttime light radiation within each planned land area: using the spatial mapping relationship between the total nighttime light radiation within the planned land area and the effective buildings within the planned land area, the effective buildings within each planned land area in the area to be evaluated are distributed across each planned land area; wherein, the calculation method for the effective buildings within the planned land area is: the effective buildings are the product of the number of buildings in the entire area to be evaluated and a second ratio, wherein the second ratio is: let N2 be the total number of planned land areas in the area to be evaluated, and let N1 be the number of planned land areas in the area to be evaluated whose total nighttime light radiation is greater than the average of the total nighttime light radiation of all planned land areas, then the ratio of N1 to N2 is used as the second ratio.

3. The method for rapidly estimating the spatial distribution of land efficiency according to claim 1, characterized in that, The discontinuous duration condition is as follows: In the population change scanning area, if the average value of the stable light intensity in the corresponding area of ​​the nighttime light image collected at the corresponding time of the current high population area is less than the average value of the stable light intensity in the corresponding area of ​​the nighttime light image of the initial cluster area in the planned land boundary area, then the current high population area is marked as meeting the discontinuous duration condition.

4. The method for rapidly estimating the spatial distribution of land efficiency according to claim 3, characterized in that, The discontinuous duration condition is replaced with: the time when the current high-population zone first appears is the start time ST; in the population change scanning area, the duration between the time when the initial agglomeration area first appears in the planned land boundary area and the start time ST of the current high-population zone is the radiation start duration; The duration from the end of the activation period to the moment when the average gray value of all points on the edge of the current high-population zone first exceeds the contrast gray value or A1 is the radiation reduction duration. If the radiation reduction duration is less than the radiation activation duration, and the average stable light intensity in the corresponding area of ​​the nighttime light image collected at the corresponding moment of the current high-population zone is less than the average stable light intensity in the corresponding area of ​​the nighttime light image of the initial gathering area, then the current high-population zone is marked as meeting the discontinuous duration condition.

5. The method for rapidly estimating the spatial distribution of land efficiency according to claim 1, characterized in that, In S400, the method for obtaining the corrected boundary by boundary correction of the boundary to be repaired is as follows: In the planning land boundary area, the point with the highest stable light intensity in the corresponding area of ​​the high-population hot zone that meets the discontinuous duration condition is designated as P1, and the point with the lowest stable light intensity is designated as P2. The point on the boundary to be repaired with the smallest difference in stable light intensity between P1 and P3 is designated as P3, and the point on the boundary to be repaired with the smallest difference in stable light intensity between P2 and P4 is designated as P4. The shortest curve segment on the boundary to be repaired between P3 and P4 is designated as the repair curve. The extracted curve is used on the boundary of the high-population hot zone that meets the discontinuous duration condition in the planning land boundary area, passing between P1 and P2. 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 then stitched onto the deleted repair curve. The boundary to be repaired at this point is designated as the corrected boundary.

6. The method for rapidly estimating the spatial distribution of land efficiency according to claim 5, characterized in that, In S400, the method of obtaining the corrected boundary by boundary correction of the boundary to be repaired is replaced by: The source region is defined as the region corresponding to the high-population-density area with the highest average stable light intensity among the corresponding regions of the high-population-density area that meets the discontinuous duration condition within the planned land boundary area. The target region is defined as the region corresponding to the high-population-density area with the lowest average stable light intensity among the corresponding regions of the high-population-density area that meets the discontinuous duration condition within the planned land boundary area. The initial intensity is defined as the difference between the average stable light intensity of all points on the boundary of the initial cluster area and the boundary to be repaired. The associated intensity is defined as the difference between the average stable light intensity of all points on the boundary of the associated cluster area and the boundary to be repaired. If the initial intensity is greater than the associated intensity, the boundary line of the source region is defined as the extraction boundary; otherwise, the boundary line of the target region is defined as the extraction boundary. The point with the highest stable light intensity on the extraction boundary is defined as BP, the point with the lowest stable light intensity is defined as SP, and the shortest curve segment passing through BP and SP on the extraction boundary is defined as the extraction curve. The point with the highest stable light intensity on the boundary to be repaired is designated as BP1, and the point with the lowest stable light intensity is designated as SP1. The shortest curve segment on the boundary to be repaired between BP1 and SP1 is designated as the curve to be repaired. The curve to be repaired on the boundary to be repaired is then deleted. The extracted curve is rotated and enlarged proportionally according to the curve to be repaired. The extracted curve is then stitched onto the deleted curve to be repaired. The boundary to be repaired at this point is recorded as the correction boundary.

7. A rapid estimation system for the spatial distribution of land efficiency, characterized in that, The rapid estimation system for the spatial distribution of land efficiency includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of any of the rapid estimation methods for the spatial distribution of land efficiency according to claims 1-6.

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