Ridge type recognition method and device based on morphological features

Abstract

The application discloses a ridge type recognition method and device based on morphological characteristics, which comprises the following steps: (1) reading two-dimensional ridge line data and DEM data to form a ridge line point set SL and a grid data set GeoDEM; (2) adding an elevation value to the points in the point set SL based on the GeoDEM; (3) extracting extreme value points in the SL and dividing mountain peak bands according to the extreme value points, and calculating morphological parameters k of each mountain peak band; (4) iteratively segmenting the ridge line based on the morphological parameters k, storing the morphological parameter set corresponding to the ridge line segmentation into a set KJ, and generating a point set set PJ of each ridge line segmentation; (5) for each parameter ksq in the KJ, calculating a length ratio LR, a compactness E and a mountain peak vector angle θ based on the set PJ, and identifying the type of the ridge line segmentation according to a preset threshold. The application has high efficiency and high accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of geographic information technology, and particularly relates to a ridge type recognition method and device based on morphological features. BACKGROUND

[0002] A ridge is a convex landform shape extending in a strip shape formed by the combination of two slopes with opposite slopes and different slopes. The top of a single mountain forming a ridge has different shapes, such as round, flat top, sharp edge, etc. When multiple mountains are continuously combined and repeatedly appear, four different ridge types can be formed: flat continuous ridge, comb-shaped ridge, undulating ridge, and jagged ridge. Different ridge shapes and types are related to the occurrence of rock layers, the uniformity of rocks, and the weathering resistance. In particular, when they continuously appear or regularly appear along a straight line in a plane, they are usually a reflection of rock property changes or structural phenomena. For example, a jagged ridge is usually formed by relatively hard rock layers due to joint and fracture development.

[0003] Ridge type recognition is an important part of landform type recognition. At present, domestic and foreign scholars have conducted certain researches on terrain recognition, ridge and valley line extraction, etc. However, the research on ridge shape judgment is relatively less, and is mainly based on manual discrimination of ridge lines. Manual discrimination of ridge types has a large workload, low efficiency, and the results are greatly affected by the subjectivity of different discriminators, and the accuracy and consistency of the results are difficult to guarantee. SUMMARY

[0004] The present application aims to provide a ridge type recognition method and device based on morphological features with higher efficiency and higher accuracy to solve the problems in the prior art.

[0005] The technical scheme of the present application is as follows:

[0006] (1) reading two-dimensional ridge line data and DEM data to form a ridge line point set SL and a grid data set GeoDEM;

[0007] (2) based on the grid data set GeoDEM, interpolating to obtain the elevation value of each point in the ridge line point set SL and adding it to the attribute of the corresponding point;

[0008] (3) based on the extreme point position of the ridge line point set SL, dividing the mountain peak wave band and calculating the morphological parameter k of each mountain peak wave band, and storing it in the morphological parameter set K;

[0009] (4) based on the morphological parameters of each mountain peak wave band, iteratively segmenting the ridge line, and storing the segmentation morphological parameter set corresponding to the ridge line segmentation in the set KJ, and corresponding to generate the set PJ of the point set mapped by each ridge line segmentation in the ridge line point set SL.

[0010] (5) Read any element ksq in set KJ and its corresponding set PJ in SL. Calculate the length ratio LR, compactness E and peak vector angle θ based on set PJ. Identify the type of ridge line segment corresponding to element ksq according to the preset threshold.

[0011] (6) Repeat step (5) until all elements in set KJ are traversed, and complete the type judgment of all ridgeline segments.

[0012] Furthermore, step (1) specifically includes:

[0013] (1-1) Read the two-dimensional ridgeline data and store it in the ridgeline point set SL = {sl} i |i=1,2,…,SLI};where sl i This represents the i-th point on the ridgeline, where i is the point number, and SLI represents the number of points in the ridgeline data.

[0014] (1-2) Read the DEM data and store it in the GeoDEM raster dataset.

[0015] Furthermore, step (3) includes:

[0016] (3-1) Traverse the ridgeline point set SL, find the maximum and minimum points in SL, and store the point indices of the maximum and minimum points in SL into the set MAX = {max i |i=1,2,…,MAXI} and MIN={min j In the sequence |j=1,2,…,MINI}, where MXI is the number of maxima, max i MINI is the index of the i-th maximum point in the ridgeline point set SL; MINI is the number of minimum points. j The index of the j-th local minimum point in the ridgeline point set SL;

[0017] (3-2) Take any two adjacent elements min from the set MIN. j min j+1 Then the corresponding point set interval in the ridgeline point set SL For a mountain peak band, The minth ridgeline j min j+1 Points; find the value in the set MAX that lies within the interval (min) j min j+1 any element max in ) i Based on the minimum points in the ridgeline point set SL and Maximum point The mountain peak band [sl] is calculated according to the following formula. a ,…,sl b The morphological parameter k is determined and stored in the morphological parameter set K;

[0018]

[0019] In the formula, Maximum point Elevation Minimum point elevation, Minimum point The elevation, l1 represents the maximum point. and the minimum point The horizontal distance, l2 represents the maximum point. and the minimum point Horizontal distance;

[0020] (3-3) Repeat step (3-2) until any two adjacent elements in set MIN have been traversed, resulting in the morphological parameter set K = {k p |p=1,2,…,KI},k p represents the morphological parameters of the p-th peak band, and KI represents the number of peak bands in SL.

[0021] Furthermore, step (4) includes:

[0022] (4-1) For each morphological parameter k in the morphological parameter set K p Calculate the interval [k1,…,k p The mean and interval [k] p ,…,k KI The absolute value of the difference between the means of and , denoted as d. p , and store it as the p-th element in set D = {d p |p=1,2,…,KI-1}, where KI represents the number of mountain peak bands in SL, and k1, k... KI It is the first and last element in the morphological parameter set K;

[0023] (4-2) Find the maximum value d in set D. m If d m If ≥r, then the ridgeline is d m The corresponding m-th peak band is divided into two ridgeline segments, and the morphological parameter set [k1,…,k] corresponding to the two ridgeline segments is... m ]、[k m+1 ,…,k KIis stored in set KJ and set D is emptied; if d m r, the ridge line segment does not need to be segmented, where r is a preset threshold, k m is the morphological parameter of the mth peak wave band;

[0024] (4-3) For the morphological parameter set of each ridge line segment in set KJ, steps (4-1) and (4-2) are iteratively executed until each ridge line segment in set KJ cannot be segmented any more. During the iterative process, when a ridge line segment can be segmented, the morphological parameter set of the current ridge line segment in set KJ is updated to the morphological parameter sets of the two ridge line segments obtained after segmentation. After the iteration, set KJ = {ksq|q = 1, 2, …, KJN} is obtained, where ksq represents the morphological parameter set of the qth ridge line segment, and KJN represents the number of ridge line segments;

[0025] (4-4) For any element ksq in set KJ, all peak wave bands included therein are obtained, and the point set interval included in the all peak wave bands is obtained from ridge line point set SL, and is sequentially stored in set PJ = {pq|q = 1, 2, …, KJN}, where pq represents the qth ridge line segment in set SL, pq = {pq g |g = 1, 2, …, Pq}, where pq g represents the gth point in point set pq, and Pq represents the number of points in the qth ridge line segment.

[0026] Further, step (5) comprises:

[0027] (5-1) Any element ksq in set KJ is obtained, and the corresponding point set pq in set PJ is obtained, and the length ratio LR is calculated according to the following formula:

[0028]

[0029] In the formula, length 3d is the length of the three-dimensional ridge line segment, Pq represents the number of points in the qth ridge line segment, x g is the X coordinate of the gth point pq g in point set pq g , y g is the Y coordinate of point pq g , h g is the elevation value of point pq 2d , and length

[0030] (5-2) If LR≤lr, the ridge line segment corresponding to ksq is determined to be a flat continuous ridge. The element ksq is deleted from the set KJ, the point set pq is stored in the flat continuous ridge set R1, and the point set pq is deleted from the set PJ. The ridge line type information is improved and step (6) is executed. Otherwise, step (5-3) is executed. Where lr is the preset length ratio threshold.

[0031] (5-3) For an element ksq, the compactness E is calculated based on its corresponding point set pq using the following formula:

[0032]

[0033] In the formula, H is the average height of the ridgeline segments, and A is the area enclosed by the average height of the ridgeline segments and the ridgeline segments.

[0034] (5-4) If E≤e, the ridge line corresponding to ksq is segmented and determined as a comb ridge. The element ksq is deleted from the set KJ. The point set pq is stored in the comb ridge set R2 and the point set pq is deleted from the set PJ. The ridge line type information is improved and step (6) is executed. Otherwise, step (5-5) is executed. Where e is the preset compactness threshold.

[0035] (5-5) For element ksq, based on its corresponding point set pq, calculate the angle θ between the peak vectors of the ridge line segments, and judge the undulating ridge and the sawtooth ridge according to the preset peak vector angle threshold angle.

[0036] Furthermore, step (5-5) includes:

[0037] (5-5-1) For element ksq, find the extreme points in the point set pq, and store the indexes of the extreme points in the point set pq into the set EX = {ex}. u |u=1,2,…,EXJ}, where ex u EXJ represents the index of the u-th extreme point in the point set pq, and EXJ represents the number of extreme points.

[0038] (5-5-2) Select any element ex from set EX. u If element ex u In the corresponding point set pq, the ex-th u Points Let be a local minimum point of the point set pq, then the ith point is e^x. u+2 Points It is also a local minimum point of the point set pq, the ex-th point. u+1 Points Let pq be a local maximum point. In this mountain peak band, from point and The vector formed by the point is denoted as From point and The vector formed by the point is denoted as Calculate the vector angle θ of the mountain peak band according to the following formula and store it in set A, where t is a preset value;

[0039]

[0040] (5-5-3) Repeat step (5-5-2) until all elements in set EX have been traversed, resulting in set A = {a v |v=1,2,…,AJ}, where a v AJ represents the vector angle of the v-th peak band in the point set pq, and AJ represents the number of peak bands.

[0041] (5-5-4) Calculate the mean avg of each element in set A. If avg ≤ angle, then determine that the ridge line segment corresponding to element ksq is a sawtooth ridge. Delete element ksq from set KJ, store point set pq into the sawtooth ridge set R3, and delete pq from set PJ. Otherwise, determine that the ridge line segment corresponding to element ksq is a wavy ridge. Delete element ksq from set KJ, store pq into the wavy ridge set R4, and delete pq from set PJ. Clear set A and set EX and complete the ridge line type information.

[0042] The ridge type identification device based on morphological features of the present invention includes a processor and a computer program stored in a memory and executable on the processor. When the processor executes the program, it implements the above-described method.

[0043] Beneficial effects: Compared with the prior art, the significant advantages of this invention are: this invention realizes the automatic identification of ridge types, and the accuracy of the identification results and the operating efficiency are relatively high. Attached Figure Description

[0044] Figure 1 These are the DEM data and ridgeline data used in the embodiments of the present invention;

[0045] Figure 2 This is a flowchart of the automatic ridge type identification method based on morphological features provided by the present invention;

[0046] Figure 3 This is a schematic diagram of the parameters in the formula for calculating the morphological parameter k;

[0047] Figure 4 This is a schematic diagram of the parameters in the length ratio LR calculation formula;

[0048] Figure 5 This is a schematic diagram of the parameters in the formula for calculating compactness E;

[0049] Figure 6 is an average vector angle θ calculation schematic diagram;

[0050] Figure 7 is a ridge line segmentation result map of an embodiment of the present application;

[0051] Figure 8 is a two-dimensional display map of a discrimination result of an embodiment of the present application;

[0052] Figure 9 is a three-dimensional display map of a discrimination result of an embodiment of the present application;

[0053] Figure 10 is a structural diagram of a ridge type automatic identification device based on morphological features provided by the present application. DETAILED DESCRIPTION

[0054] The technical solution of the present application will be further described in detail below. The experimental data of the present embodiment uses 30m resolution DEM data of Ganzi Tibetan Autonomous Prefecture in Sichuan Province. The projection coordinate system used by the DEM is WGS_1984_UTM_Zone_47N. The present embodiment will be further described by combining the accompanying drawings and describing a specific embodiment.

[0055] The present embodiment provides a ridge type automatic identification method based on morphological features, as shown in Figure 2 , specifically comprising the following steps:

[0056] (1) reading two-dimensional ridge line data and DEM data to form a ridge line point set SL and a grid data set GeoDEM.

[0057] This step specifically comprises:

[0058] (1-1) reading two-dimensional ridge line data and storing it in a ridge line point set SL = {sl i | i = 1, 2, …, SLI}; wherein sl i represents the i-th point of the ridge line, i is the point serial number, and SLI represents the number of points in the ridge line data; in the present embodiment SLI = 840;

[0059] (1-2) reading DEM data and storing it in a grid data set GeoDEM.

[0060] (2) based on the grid data set GeoDEM, interpolating to obtain the elevation value of each point in the ridge line point set SL and adding it to the attribute of the corresponding point;

[0061] (3) based on the extreme point position of the ridge line point set SL, dividing the mountain peak wave band and calculating the morphological parameter k of each mountain peak wave band, and storing it in a morphological parameter set K;

[0062] This step specifically comprises:

[0063] (3-1) Traverse the ridgeline point set SL, find the maximum and minimum points in SL, and store the point indices of the maximum and minimum points in SL into the set MAX = {max i |i=1,2,…,MAXI} and MIN={min j In the sequence |j=1,2,…,MINI}, where MXI is the number of maxima, max i MINI is the index of the i-th maximum point in the ridgeline point set SL; MINI is the number of minimum points. j The index of the j-th local minimum point in the ridgeline point set SL; in this embodiment, MAXI = 31, MINI = 31;

[0064] (3-2) Take any two adjacent elements min from the set MIN. j min j+1 Then the corresponding point set interval in the ridgeline point set SL For a mountain peak band, The minth ridgeline j min j+1 Points; find the value in the set MAX that lies within the interval (min) j min j+1 any element max in ) i Based on the minimum points in the ridgeline point set SL and Maximum point The mountain peak band [sl] is calculated according to the following formula. a ,…,sl b The morphological parameter k is determined and stored in the morphological parameter set K;

[0065]

[0066] In the formula, Maximum point Elevation Minimum point elevation, Minimum point The elevation, l1 represents the maximum point. and the minimum point The horizontal distance, l2 represents the maximum point. and the minimum point Horizontal distance, such as Figure 3 As shown;

[0067] (3-3) cyclically execute step (3-2) until any two adjacent elements in the set MIN are traversed, and a set of morphological parameters K = {k p |p = 1, 2, …, KI} is obtained, where k p represents the morphological parameter of the pth peak band, and KI represents the number of peak bands in SL.

[0068] (4) based on the morphological parameters of each peak band, the ridge line is iteratively segmented, and the segmented morphological parameter set corresponding to the ridge line segmentation is stored in the set KJ, and the set PJ of the point set mapped by each ridge line segmentation in the point set SL of the ridge line point set SL is generated;

[0069] This step specifically includes:

[0070] (4-1) for each morphological parameter k p in the set of morphological parameters K, the absolute value of the difference between the mean value of the interval [k p ] and the mean value of the interval [k p ,…,k KI ] is calculated, and is recorded as d p , and is stored in the set D = {d p |p = 1, 2, …, KI-1} as the pth element, where KI represents the number of peak bands in SL, and k KI and k m are the first and last elements in the set of morphological parameters K;

[0071] (4-2) query the maximum value d m in the set D; if d m ≥ r, the ridge line is divided into two ridge line segments with the mth peak band corresponding to d m , the morphological parameter sets [k m+1 ,…,k KI ] corresponding to the two ridge line segments are stored in the set KJ, and the set D is emptied; if d m < r, the ridge line does not need to be segmented, where r is a preset threshold, k m is the morphological parameter of the mth peak band, and r = 0.105 in this embodiment;

[0072] (4-3) For the morphological parameter set of each ridge line segment in the set KJ, the steps (4-1) and (4-2) are iteratively executed until each ridge line segment in the set KJ cannot be segmented again, and during the iteration process, when the ridge line segment can be segmented again, the morphological parameter set of the current ridge line segment in the set KJ is updated to the morphological parameter sets of the two ridge line segments obtained after segmentation, and after the iteration, the set KJ = {ksq | q = 1, 2, …, KJN} is obtained, where ksq represents the morphological parameter set of the qth ridge line segment, KJN represents the number of ridge line segments, and in this embodiment, KJN = 3. The segmentation result is as shown in FIG. 8. Figure 7

[0073] (4-4) For any element ksq in the set KJ, all peak wave bands included therein are obtained, and the point set interval included in the all peak wave bands is obtained from the ridge line point set SL, and is sequentially stored in the set PJ = {pq | q = 1, 2, …, KJN}, where pq represents the qth ridge line segment in the point set SL, pq = {pqg | g = 1, 2, …, Pq}, where pqg represents the gth point in the point set pq, and Pq represents the number of points in the qth ridge line segment, and in this embodiment, P1 = 104, P2 = 478, and P3 = 258. g g

[0074] (5) Any element ksq in the set KJ is read, the length ratio LR, the compactness E, and the peak vector angle θ are calculated based on the set PJ, and according to a preset threshold, the type of the ridge line segment corresponding to the element ksq is identified.

[0075] This step specifically includes:

[0076] (5-1) Any element ksq in the set KJ is obtained, and the point set pq corresponding thereto is obtained from the set PJ, and the length ratio LR is calculated according to the following formula:

[0077]

[0078] In the formula, length 3d is the length of the three-dimensional ridge line segment, Pq represents the number of points in the qth ridge line segment, x g is the X coordinate of the gth point pqg g in the point set pq, y g is the Y coordinate of the point pqg g , and h g is the elevation value of the point pqg g , length 2d is the length of the three-dimensional ridge line segment projected on a plane, as shown in FIG. 9. Figure 4

[0079] ​​​​(5-2) If LR≤lr, then the ridgeline segment corresponding to ksq is determined as a flat continuous ridge, the element ksq is deleted from the set KJ, the point set pq is stored in the set of flat continuous ridges R1, and the point set pq is deleted from the set PJ. The ridgeline type information is then completed and step (6) is executed. Otherwise, step (5-3) is executed. Wherein, lr is a preset length ratio threshold. In this embodiment, lr=1.090, LR ks1 =1.058, LR ks2 =1.167, LR ks3 =1.056, the number of flat continuous ridges in set R1 is 2;

[0080] (5-3) For an element ksq, the compactness E is calculated based on its corresponding point set pq using the following formula:

[0081]

[0082] In the formula, H is the average height of the ridgeline segments, and A is the area enclosed by the average height of the ridgeline segments and the ridgeline segments themselves. Figure 5 As shown;

[0083] (5-4) If E≤e, then the ridgeline corresponding to ksq is segmented and determined as a comb ridge. The element ksq is deleted from the set KJ, the point set pq is stored in the comb ridge set R2, and the point set pq is deleted from the set PJ. The ridgeline type information is then completed, and step (6) is executed. Otherwise, step (5-5) is executed. Where e is a preset compactness threshold. In this embodiment, e=0.35, E ks1 =0.839, the number of comb-shaped ridge sets R2 is 0;

[0084] (5-5) For element ksq, based on its corresponding point set pq, calculate the angle θ between the peak vectors of the ridge line segments, and judge the undulating ridge and the sawtooth ridge according to the preset peak vector angle threshold angle.

[0085] This step specifically includes:

[0086] (5-5-1) For element ksq, find the extreme points in the point set pq, and store the indexes of the extreme points in the point set pq into the set EX = {ex}. u |u=1,2,…,EXJ}, where ex u EXJ represents the index of the u-th extreme point in the point set pq, and EXJ represents the number of extreme points.

[0087] (5-5-2) Select any element ex from set EX. u If element ex u In the corresponding point set pq, the ex-th u Points is a minimum point of the point set pq, the ex u+2 th point is also a minimum point of the point set pq, the ex u+1 th point is a maximum point of the point set pq, in this peak segment, the vector formed by the point and the point is denoted as the vector formed by the point and the point is denoted as The vector angle θ of the peak segment is calculated according to the following formula and stored in the set A, t is a preset value, in this embodiment, t = 3;

[0088]

[0089] (5-5-3) Step (5-5-2) is executed in a loop until all elements in the set EX are traversed, obtaining the set A = {a v |v = 1, 2, …, AJ}, wherein a v represents the vector angle of the vth peak segment in the point set pq, and AJ represents the number of peak segments;

[0090] (5-5-4) The average value avg of the elements in the set A is calculated, if avg≤angle, it is determined that the ridge line segment corresponding to the element ksq is a jagged ridge, the element ksq is deleted from the set KJ, the point set pq is stored in the jagged ridge set R3 and deleted from the set PJ; otherwise, it is determined that the ridge line segment corresponding to the element ksq is a wavy ridge, the element ksq is deleted from the set KJ, pq is stored in the wavy ridge set R4 and deleted from the set PJ, the set A and the set EX are emptied, and the ridge line type information is perfected, in this embodiment, angle = 140.0, avg ks1 = 130.7, the number of elements in the jagged ridge set R3 is 1, and the number of elements in the wavy ridge set is 0.

[0091] (6) Step (5) is executed in a loop until all elements in the set KJ are traversed, completing the type judgment of all ridge line segments, and the final classification judgment result is as shown in Figure 8 and Figure 9 .

[0092] Example Two

[0093] Figure 10 is a structure diagram of a ridge type recognition device based on morphological features provided in Example Three of the present application, the present embodiment provides services for the implementation of the method of Example One of the present application, Figure 10A block diagram of an exemplary device 12 suitable for implementing embodiments of the present invention is shown. Figure 10 The device 12 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of the present invention.

[0094] like Figure 10 As shown, device 12 is represented as a general-purpose computing device. Components of device 12 may include, but are not limited to: one or more processors or processing units 16, system memory 28, and a bus 18 connecting different system components, including system memory 28 and processing unit 16.

[0095] Bus 18 represents one or more of several bus architectures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor, or a local bus using any of the various bus architectures. For example, these architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnect (PCI) bus.

[0096] Device 12 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by device 12, including volatile and non-volatile media, removable and non-removable media.

[0097] System memory 28 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. Device 12 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, storage system 34 may be used to read and write non-removable, non-volatile magnetic media (…). Figure 10 Not shown; usually referred to as a "hard drive"). Although Figure 10 Not shown, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk") and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to bus 18 via one or more data media interfaces. Memory 28 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments of the present invention.

[0098] Program / utility 40 having a set of program modules 42 can be stored in memory 28 by way of example, such program modules 42 include an operating system, one or more application programs, other program modules, and program data, each or some combination thereof, which can include implementation of the network environment in each or some combination of the above examples. Program modules 42 generally carry out the functions and / or methodologies of embodiments of the application as described herein.

[0099] Device 12 can also communicate with one or more external devices 14 such as a keyboard or pointing device, a display 24, etc.; one or more devices that enable a user to interact with device 12; and / or one or more devices that enable device 12 to communicate with one or more other computing devices. Such communication can occur via Input / Output (I / O) interface(s) 22. Still yet, device 12 can communicate with one or more networks, such as one or more local area networks (LAN), wide area networks (WAN), and / or public networks, such as the Internet, via network adapter 20. As depicted, network adapter 20 communicates with the other components of device 12 via bus 18. It should be appreciated that although not shown, other hardware and / or software modules could be used in conjunction with device 12. Such ​ modules include, but are not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data archival storage systems, etc.

[0100] Processing unit(s) 16 can execute instructions, for example, stored in system memory 28, to implement methods of embodiments of the present application.

Claims

1. A method of ridge type identification based on morphological features, characterized by The method comprises: (1) reading two-dimensional ridge line data and DEM data to form a ridge line point set SL and a grid data set GeoDEM; (2) based on the grid data set GeoDEM, the elevation values of the points in the ridge line point set SL are obtained by interpolation and added to the attributes of the corresponding points; (3) based on the extreme point position of the ridge line point set SL, the mountain peak wave band is divided and the morphological parameters k of each mountain peak wave band are calculated and stored in the morphological parameter set K; (4) based on the morphological parameters of each mountain peak wave band, the ridge line is iteratively segmented, and the segmented morphological parameter set corresponding to the ridge line segmentation is stored in the set KJ, and the set PJ of the point set mapped by each ridge line segmentation in the ridge line point set SL is generated; (5) reading any element ksq in the set KJ, calculating the length ratio LR, compactness E and the mountain vector angle based on the set PJ and identifying the type of the ridge line segment corresponding to the element ksq according to a preset threshold. (6) step (5) is executed in a loop until all elements in set KJ are traversed, and the type judgment of all ridge line segmentations is completed; Step (5) comprises: (5-1) obtaining any element ksq in set KJ and its corresponding point set pq from set PJ, and calculating the length ratio LR according to the following formula: ， In the formula, length 3d It is the length of the 3D ridgeline segment, Pq represents the number of midpoints in the q-th ridgeline segment, and x g It is the g-th point pq in the point set pq. g X coordinates, y coordinates g It's point PQ. g The Y-coordinate, h g It's point PQ. g Elevation value, length 2d It is the length of the segmented projection of the three-dimensional ridgeline onto the plane; (5-2) if LR≤lr, the ridge line segmentation corresponding to ksq is determined as a flat continuous ridge, the element ksq is deleted in set KJ, the point set pq is stored in the flat continuous ridge set R1, the point set pq is deleted in set PJ, the ridge line type information is perfected, and step (6) is executed, otherwise step (5-3) is executed, wherein lr is a preset length ratio threshold; (5-3) for element ksq, the compactness E is calculated according to the following formula based on its corresponding point set pq: ， In the formula, H is the average height of the ridge line segmentation, and A is the average height of the ridge line segmentation and the area enclosed by the ridge line segmentation; (5-4) if E≤e, the ridge line segmentation corresponding to ksq is determined as a comb-shaped ridge, the element ksq is deleted in set KJ, the point set pq is stored in the comb-shaped ridge set R2 and deleted in set PJ, the ridge line type information is perfected, and step (6) is executed, otherwise step (5-5) is executed, wherein e is a preset compactness threshold; (5-5) For the element ksq, based on its corresponding point set pq, calculate the ridge line of the mountain peak vector angle According to the preset mountain peak vector angle threshold angle, the judgment of the undulating ridge and the jagged ridge is carried out; Step (5-5) comprises: (5-5-1) For element ksq, find the extreme points in point set pq, and store the sequence number of the extreme points in point set pq into set EX = {ex u |u = 1, 2, …, EXJ} in turn, where ex u represents the sequence number of the u-th extreme point in point set pq, and EXJ represents the number of extreme points; (5-5-2) Select any element ex from set EX. u If element ex u In the corresponding point set pq, the ex-th u pq exu Let be a local minimum point of the point set pq, then the ith point is e^x. u+2 pq exu+2 It is also a local minimum point of the point set pq, the ex-th point. u+1 pq exu+1 Let p be a local maximum point of the point set pq, in [pj exu ,…,pq exu+2 In this mountain peak band, from point pq exu+2-t With PQ exu+2 The vector formed by the point is denoted as , from point pq exu+2+t With PQ exu+2 The vector formed by the point is denoted as The vector angle of the mountain peak band is calculated according to the following formula. And store it in set A, where t is a preset value; ， (5-5-3) Recursively execute step (5-5-2) until all elements in set EX are traversed, and set A = {a v |v = 1, 2, …, AJ} is obtained, where a v represents the vector angle of the vth peak band in the point set AJ represents the number of peak bands. (5-5-4) calculating the average value avg of each element in set A, if avg≤angle, the ridge line segmentation corresponding to element ksq is determined as a zigzag ridge, the element ksq is deleted in set KJ, the point set pq is stored in the zigzag ridge set R3 and deleted in set PJ; otherwise, the ridge line segmentation corresponding to element ksq is determined as a wave-shaped ridge, the element ksq is deleted in set KJ, the pq is stored in the wave-shaped ridge set R4 and deleted in set PJ, the set A and the set EX are emptied, and the ridge line type information is perfected.

2. The morphological feature based ridge type identification method as claimed in claim 1, wherein: Step (1) specifically comprises: (1-1) Read the two-dimensional ridge line data and store it in the ridge line point set SL={sl i | i = 1, 2, …, SLI}; wherein sl i represents the i-th point of the ridge line, i is the point serial number, and SLI represents the number of points in the ridge line data. (1-2) reading DEM data and storing it in grid data set GeoDEM. 3.The morphological feature based ridge type identification method of claim 1, wherein: Step (3) comprises: (3-1) Traverse the ridge line point set SL, find the maximum point and the minimum point in the ridge line point set SL, and store the point sequence number of the maximum point and the minimum point in the ridge line point set SL in the set MAX={max i |i=1,2,…,MAXI} and MIN={min j |j=1,2,…,MINI} respectively, where MAXI is the number of maximum points, max i is the sequence number of the ith maximum point in the ridge line point set SL; MINI is the number of minimum points, min j is the sequence number of the jth minimum point in the ridge line point set SL; (3-2) Find two adjacent elements min j , min j+1 in the set MIN minj , then the corresponding point set interval [sl minj+1 ,…,sl minj ] in the ridge line point set SL is a peak segment, sl minj+1 , sl j denote the min j+1 , min j th point of the ridge line; find any element max j+1 in the set MAX whose value is in the interval (min i , min minj ), based on the minimum point sl minj+1 and the maximum point sl maxi in the ridge line point set SL, calculate the shape parameter k of the peak segment [sl a ,…,sl b ] according to the following formula, and store k in the shape parameter set K; ， wherein , is a maximum point elevation, is a minimum point sl minj elevation of the maximum point sl , is a minimum point elevation of the minimum point l 1 represents the horizontal distance of the maximum point sl maxi from the minimum point sl minj , l 2 represents the horizontal distance of the maximum point from the minimum point ; (3-3) The step (3-2) is executed cyclically until any two adjacent elements in the set MIN are traversed, and the morphology parameter set K={k p |p=1,2,…,KI},k p represents the morphology parameter of the pth peak band, and KI represents the number of peak bands in SL.

4. The morphological feature based ridge type identification method of claim 3, wherein: Step (4) comprises: (4-1) For each morphological parameter k in the morphological parameter set K p Calculate the interval [k1,…, k p The mean and interval [k] p ,…, k KI The absolute value of the difference between the means of and , denoted as d. p , and store it as the p-th element in the set D={d p |p=1,2,…,KI-1}, where KI represents the number of mountain peak bands in SL, and k1, k... KI It is the first and last element in the morphological parameter set K; (4-2) Query the maximum value d of elements in set D m ; if d m ≥ r, the ridge line is divided into d m segments, and the corresponding morphological parameter set [k m , …, k m+1 , …, k KI ] of the two ridge line segments is stored in set KJ, and set D is emptied; if d m < r, the segment of the ridge line does not need to be segmented, wherein r is a preset threshold, and k m is the morphological parameter of the mth peak wave band. (4-3) for each ridge line segment in the set KJ, the steps (4-1), (4-2) are executed in a loop until each ridge line segment in the set KJ cannot be segmented any more, in the loop, when a ridge line segment can be segmented, the set of morphological parameters of the current ridge line segment in the set KJ is updated to the set of morphological parameters of the two ridge line segments obtained after segmentation, after the loop, the set KJ={ksq|q=1,2,…,KJN} is obtained, ksq represents the set of morphological parameters of the qth ridge line segment, and KJN represents the number of ridge line segments; (4-4) For any element ksqin the set KJ, get all the peak bands included by it, and get the point set interval included by the all the peak bands from the ridge line point set SL, and store them into the set PJ={pq|q=1,2,…,KJN} in turn, where pq represents the qth ridge line segment in the point set corresponding to the set SL, pq={pq g |g=1,2,…,Pq} where pq g represents the gth point in the point set pq, and Pq represents the number of points in the qth ridge line segment.

5. A morphological feature based ridge type identification apparatus comprising a processor and a computer program stored on a memory and executable on the processor, characterized in that: The processor implements the method in any one of claims 1-4 when executing the program.

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