TWI542898B - Method of cloud representative position location - Google Patents

Description

Cloud layer representation location location method

The invention relates to a cloud layer representative position localization method, in particular to a positioning method for judging a representative position of a cloud layer according to a thickness of a cloud layer.

Clouds are one of the main factors affecting the change of weather and rain. When the clouds above a region are too thin, the rain rate in the area is usually not high. When the clouds above the area are thicker in real time, the area usually has a higher Rain rate, therefore, cloud information can be used not only to judge weather conditions, but also as a reference for government agencies to implement related plans or contingency measures. For example, rain-fighting teams can use cloud information to determine the spatial location suitable for rain-producing areas, or rainfall. The monitoring center can use the cloud information to predict the rain conditions in each area, and then instantly monitor areas where heavy rains may occur.

The most common way to determine the location of the cloud is to observe a meteorological cloud map. To put it simply, the meteorological cloud map is taken from the meteorological satellite set at high altitude, or generated by the ground-mounted Doppler radar. The meteorological cloud map not only shows the distribution of clouds in the atmosphere, but also the cloud layer and the ground. The relative position of the meteorological cloud map can be divided into infrared satellite cloud image, visible satellite image and radar echo map.

In the case of a cluster of clouds, the cloud layer usually has different thicknesses in different regions, and the cloud layer has a centroid position according to the thickness distribution condition, since the centroid position is usually the most influential weather. Therefore, the centroid position can be regarded as the representative position of the cloud layer. However, in the judgment of the position of the cloud, it is customary to view the meteorological cloud image only through the human eye. Or draw a contour map to determine the range covered by the cloud in the meteorological cloud map. The above method can only show the difference of the distribution of the cloud layer or the thickness of the cloud layer, and the representative position of the cloud layer cannot be judged according to the thickness distribution of the cloud layer, so that the cloud layer The judgment of the representative position is not clear enough to accurately locate the representative position of the cloud.

In view of this, it is necessary to provide a cloud layer representative location positioning method to solve the problem that the conventional cloud layer represents inaccurate location location.

The object of the present invention is to provide a cloud layer representative position localization method, which can calculate the representative position of the cloud layer according to the thickness of the cloud layer, thereby improving the positioning accuracy of the representative position of the cloud layer.

In order to achieve the foregoing object, the technical means for the present invention includes: a cloud layer representative position localization method, which is executed by a processor, and the steps include: an image selection step, selecting a region range in a weather cloud map, and a plane coordinate represents the range of the region; a quantization step, performing a quantization process on the region range to obtain intensity values of the plurality of pixel points included in the region range; a calculation point determination step, setting a threshold range, and In the range of the region, the plurality of pixel points whose intensity values are within the threshold value range are regarded as a plurality of operation points, and the plurality of operation points respectively have a representative position according to the plane coordinates; and a centroid operation Step, substituting the representative position and the intensity value of the plurality of operation points into a centroid calculation formula to calculate a centroid position, and using the centroid position as a cloud representative position of the region range, performing the centroid After the operation step, another coordinate conversion step is performed, and the coordinate conversion step converts the cloud representative position from the plane coordinate value to the latitude and longitude coordinate .

Wherein, in the image selection step, the weather cloud image is a radar echo map.

In the quantization step, the quantization process first converts the image of the region range into a grayscale image, and uses the grayscale color value as the intensity value of the plurality of pixel points included in the region range.

Wherein, in the boundary determining step, the threshold value range is a grayscale color threshold value range.

Wherein, in the centroid calculation step, the centroid calculation formula is: Wherein C _{x is} a representative position of the centroid position on the X axis of the plane coordinate; C _{y is} a representative position of the centroid position on the Y axis of the plane coordinate; n is an operation point of the range of the area The maximum representative position of the X and Y axes of the plane coordinate, and n is an integer; x is the coordinate value on the X axis of the plane coordinate; y is the coordinate value on the Y axis of the plane coordinate; m _xy is the representative position (x, y) The intensity value of the computed point at the coordinate.

In the coordinate conversion step, the latitude and longitude coordinate value of the meteorological cloud map and the plane coordinate value of the region are compared by an interpolation method to convert the cloud representative position from the plane coordinate value to the latitude and longitude coordinate value.

Accordingly, the method for positioning a cloud layer according to the present invention can determine the representative position of the cloud layer by the thickness of the cloud layer, so that the representative position of the cloud layer has a high correlation with the thickness of the cloud layer, thereby improving the positioning accuracy of the representative position of the cloud layer.

〔this invention〕

S1‧‧‧Image selection steps

S2‧‧‧Quantification step

S3‧‧‧ Calculation point judgment step

S4‧‧‧ centroid calculation steps

S5‧‧‧ coordinate conversion steps

Figure 1 is a flow chart showing the steps of the cloud layer representative position localization method of the present invention.

The above and other objects, features and advantages of the present invention will become more <RTIgt; "Cloud map" means a satellite image taken from a meteorological satellite set at a high altitude towards the ground, or a radar generated by a ground-mounted Doppler radar. The echo map, in which the meteorological cloud map can be further divided into an infrared satellite cloud image, a visible light satellite cloud image, and a radar echo map, depending on the manner of shooting.

The "grayscale color value" as used throughout the present invention refers to a numerical value representing a gray scale representing a pixel, and generally, the grayscale color value ranges from 0 to 255.

Referring to FIG. 1 , the cloud layer representative position location method of the present invention includes an image selection step S1, a quantization step S2, a calculation point determination step S3, and a centroid calculation step S4. The above steps are all performed by a processor, and the processor can be a computer or any computing processor, and can capture image data or execute a software or program on the Internet to perform operations and statistics.

The image selection step S1 is performed by selecting a region range in a weather cloud image and expressing the region range by a plane coordinate.

More specifically, the processor may download the meteorological cloud map from the Central Weather Bureau or a related website, and select the range of the region in which the cloud representative position is to be determined in the meteorological cloud map, and the range of the region may be selected according to the user's needs. And arbitrarily selected, or selected by the processor according to historical data or scheduled schedules. For example, if the geographic range covered by the meteorological cloud map includes the sea area of Taiwan and its surroundings, the processor may select only the whole of Taiwan as the Regional scope, or choose any administrative region of Taiwan as the region, and the region should preferably be the location with cloud distribution in the meteorological cloud map. The type of the meteorological cloud map is not limited herein, and any meteorological cloud map that can exhibit a difference in the thickness of the cloud layer can be applied. In the embodiment, the meteorological cloud map is a radar echo map. Moreover, the meteorological cloud image is usually represented by a latitude and longitude coordinate. To reduce the processing complexity of the subsequent steps, the processor selects the range of the region from the meteorological cloud image, and then displays a region of the region with a plane coordinate, the plane The coordinates may include an X-axis and a Y-axis such that a plurality of pixel points in the range of the region may be located in the plane coordinate, and each pixel may have a value (x, y) according to its representative position.

The quantization step S2 is performed by performing a quantization process on the region range to obtain The intensity value of several pixels included in the range of the region.

In more detail, after the processor selects the image of the region range, the quantization processing software can analyze a plurality of color values corresponding to the plurality of pixel points in the region, and use the color value as the intensity value. Wherein, when the quantization processing software performs color quantization processing on the region range, the quantized color value may be represented by three primary colors (red, green, blue) or by grayscale color, and is not limited herein. In order to reduce the processing complexity of the subsequent steps, in the embodiment, the quantization process first converts the image of the region range into a grayscale image, and uses the grayscale color value as the number of pixels included in the region range. Strength value. Thereby, since the difference in thickness of the cloud layer may have different expression colors in the meteorological cloud image, the quantization step S2 may quantize the color of the pixel points in the range of the region to a corresponding value, so that the plurality of pixels are different in color. Each of the different intensity values has the effect of improving the accuracy of the subsequent cloud layer thickness.

The operation point determining step S3 is to set a threshold range, and in the range of the region, the plurality of pixel points whose intensity values are within the threshold value range are regarded as a plurality of operation points, and the plurality of operation points are determined The plane coordinates each have a representative position.

More specifically, since the thickness difference of the cloud layer will have different performance colors in the meteorological cloud image, and the cloud layer and the ground also have different performance colors in the meteorological cloud image, when the region range performs the quantization process, The plurality of pixels in the region may have different intensity values depending on the color. Then, in order to determine the thickness of the cloud in the region, the processor may set the threshold range, and the threshold may be in the cloud layer. The range of intensity values above a certain thickness, by setting the threshold value range, can treat the plurality of pixel points of the cloud layer having a certain thickness as a plurality of operation points, thereby improving the accuracy of subsequent cloud position determination. In this embodiment, the threshold value range may be a grayscale color threshold value range, and the grayscale color threshold value range may be adjusted according to actual needs, and is not limited herein. For example, in the grayscale image, the pixel point closer to white may be regarded as a cloud layer, and the grayscale color of the threshold value range may be set between white and light gray. In this embodiment, the threshold value range is the lowest. The value should be greater than 75, For example, the threshold value ranges from 75 to 255. Similarly, if the region range is color-reversed in the grayscale image, and the pixel closer to black is regarded as the cloud layer, the threshold value range is grayed out. The color of the order can be set between black and dark gray, which can be easily understood by those skilled in the art, and will not be described herein.

Moreover, since the range of the region is represented by the plane coordinate having the X axis and the Y axis, the plurality of operation points of the region range may have the representative position in the plane coordinate, and the plurality of operation points The representative position can be expressed as the coordinate value (x, y).

The centroid calculation step S4 substitutes the representative position and the intensity value of the plurality of operation points into a centroid calculation formula to calculate a centroid position, and uses the centroid position as a cloud representative position of the region range.

More specifically, since the cloud layer usually has different thicknesses at different positions within the region, and the cloud layer has the centroid position according to the thickness distribution condition, since the centroid position is usually the most influential weather. Therefore, the centroid position can be regarded as a representative position of the cloud layer. Moreover, after the weather cloud image passes through the image selection step S1 and the quantization step S2, the plurality of operation points of the region range respectively have representative position and intensity values, wherein the intensity value can represent the thickness of the cloud layer, When the plurality of operation points are substituted into the centroid calculation formula, the centroid position of the cloud layer in the region may be calculated according to the thickness distribution of the cloud layer, and the centroid position is used as the representative position of the cloud layer in the region range. In this embodiment, the centroid calculation formula is as follows:

Wherein C _{x is} a representative position of the centroid position on the X axis of the plane coordinate; C _{y is} a representative position of the centroid position on the Y axis of the plane coordinate; n is an operation point of the range of the area The maximum representative position of the X and Y axes of the plane coordinate, and n is an integer; x is the coordinate value on the X axis of the plane coordinate; y is the coordinate value on the Y axis of the plane coordinate; m _xy is the representative position (x, y) The intensity value of the computed point at the coordinate.

By performing the centroid calculation step S4, the centroid position of the cloud layer in the region can be calculated according to the thickness distribution of the cloud layer, and the centroid position can be used as the representative position of the cloud layer in the region range, and the cloud layer can be made. The representative position has a high correlation with the thickness of the cloud layer, thereby improving the positioning accuracy of the representative position of the cloud layer. When the representative position of the cloud layer is used as the meteorological reference data, the effect of improving the reference value of the meteorological reference data is obtained.

Moreover, after performing the centroid calculation step S4, the cloud layer representative position locating method of the present invention may further perform a label conversion step S5, which converts the cloud layer representative position from the plane coordinate value to the latitude and longitude coordinate value.

In more detail, since the image selection step S1 is performed, the area range is represented by the plane coordinate. Therefore, after the centroid calculation step S4 is performed and the cloud layer representative position is generated, the cloud layer representative position is still The coordinate value of the plane coordinate is indicated. At this time, if the representative position of the cloud layer is converted from the coordinate value of the cloud to the coordinate value of the latitude and longitude, and the representative position of the cloud layer is used as the meteorological reference data, the meteorological cloud map for calculating the representative position of the cloud layer is added to the meteorological reference material. Taking time, the meteorological reference data can be directly transmitted to any meteorological related institution, so that the meteorological related organization can obtain the regional range, latitude and longitude coordinates and time related to the representative position of the cloud layer from the meteorological reference data, so as to facilitate the direct meteorological agencies. The use of this meteorological reference has the effect of improving the ease of use of the data. For example, when the rain-creating group wants to execute the rain-making plan, the latitude and longitude coordinates and the relevant time of the representative position of the cloud layer can be obtained according to the meteorological reference material, and the exact position of the rain-making to be performed is determined according to the above-mentioned data, so that the This meteorological reference for the location of the cloud layer is fully utilized.

In summary, the cloud layer representative position positioning method of the present invention can calculate the centroid position according to the thickness distribution of the cloud layer, and use the centroid position as the representative position of the cloud layer, so that the representative position of the cloud layer and the thickness of the cloud layer can be compared. High correlation, which in turn improves the positioning accuracy of the representative position of the cloud.

While the invention has been described in connection with the preferred embodiments described above, it is not intended to limit the scope of the invention. The technical scope of the invention is protected, and therefore the scope of the invention is defined by the scope of the appended claims.

S1‧‧‧Image selection steps

S2‧‧‧Quantification step

S3‧‧‧ Calculation point judgment step

S4‧‧‧ centroid calculation steps

S5‧‧‧ coordinate conversion steps

Claims (6)

A cloud layer representative position localization method is performed by a processor, and the step comprises: an image selection step of selecting a region range in a weather cloud image and expressing the region range by a plane coordinate; a quantization step, the region range Performing a quantization process to obtain intensity values of a plurality of pixel points included in the range of the region; a calculation point determination step of setting a threshold range, and in the range of the region, the intensity value is within the threshold value range The plurality of pixel points are regarded as a plurality of operation points, and the plurality of operation points respectively have a representative position according to the plane coordinates; and a centroid calculation step, the representative position and the intensity value of the plurality of operation points are substituted into one The centroid calculation formula calculates a centroid position, and uses the centroid position as a cloud representative position of the region range. After performing the centroid calculation step, another label conversion step is performed, and the coordinate conversion step is performed. The cloud representative position is converted from a plane coordinate value to a latitude and longitude coordinate value. The cloud layer representative position localization method according to claim 1, wherein in the image selection step, the weather cloud map is a radar echo map. The cloud layer representative position localization method according to claim 1, wherein in the quantizing step, the quantization process first converts the image of the region range into a grayscale image, and uses the grayscale color value as the region range. The intensity value of the included pixels. The cloud layer representative position localization method according to claim 3, wherein in the boundary determining step, the threshold value range is a grayscale color threshold value range. The cloud layer representative position locating method according to claim 1, wherein in the centroid operation step, the centroid calculation formula is: Wherein Cx is a representative position of the centroid position on the X-axis of the plane coordinate; Cy is a representative position of the centroid position on the Y-axis of the plane coordinate; n is an operation point of the region range at the plane coordinate The maximum representative position of the X and Y axes, and n is an integer; x is the coordinate value on the X axis of the plane coordinate; y is the coordinate value on the Y axis of the plane coordinate; mxy is the representative position at (x, y) The intensity value of the point of operation at the coordinates. The cloud layer representative position locating method according to claim 1, wherein in the coordinate conversion step, the latitude and longitude coordinate value of the weather cloud map and the plane coordinate value of the region range are compared by an interpolation method, so as to The cloud representative position is converted from a plane coordinate value to a latitude and longitude coordinate value.