TWD97座標轉經緯度

Proj4j.java

import org.osgeo.proj4j.CRSFactory;
import org.osgeo.proj4j.CoordinateReferenceSystem;
import org.osgeo.proj4j.CoordinateTransform;
import org.osgeo.proj4j.CoordinateTransformFactory;
import org.osgeo.proj4j.ProjCoordinate;

public class Proj4j {
  /**
  * https://search.maven.org/search?q=a:proj4j 找出proj4j轉案
  * http://www.sunriver.com.tw/taiwanmap/grid_tm2_convert.php#a03 線上轉換(參考範本)
  * https://proj4.org/usage/projections.html 參數說明 lon_0: 中央經線 +lat_0: 中央緯線
  * +x_0: X 軸座標原點，向西平移 250000 units(公尺,meters) +y_0: Y 軸座標原點位在赤道
  *
  */
  public static void main(String[] args) {
    CoordinateTransformFactory ctFactory = new CoordinateTransformFactory();
    CRSFactory csFactory = new CRSFactory();
    //台灣基準
    CoordinateReferenceSystem crsTaiwan = csFactory.createFromParameters("EPSG:3826", "+title=TWD97 +proj=tmerc +lat_0=0 +lon_0=121 +k=0.9999 +x_0=250000 +y_0=0 +ellps=GRS80 +units=meters +no_defs");
    //澎湖,金門與馬祖基準
    CoordinateReferenceSystem crsPenghu = csFactory.createFromParameters("EPSG:3825", "+title=TWD97 +proj=tmerc +lat_0=0 +lon_0=119 +k=0.9999 +x_0=250000 +y_0=0 +ellps=GRS80 +units=公尺 +no_defs");
    //WGS84
    CoordinateReferenceSystem WGS84 = csFactory.createFromParameters("WGS84", "+proj=longlat +datum=WGS84 +no_defs");
    //台灣基準轉換為WGS84
    CoordinateTransform trans = ctFactory.createTransform(crsTaiwan, WGS84);
    ProjCoordinate p = new ProjCoordinate(306976.247, 2769609.563); //TGOS全國門牌地址定位服務找出台北101的TWD97座標
    ProjCoordinate p2 = new ProjCoordinate();
    ProjCoordinate p3 = trans.transform(p, p2);
    System.out.printf("Taipei 101:%.7f,%.7f\n",p2.x, p3.y);
    System.out.printf("Taipei 101:%.7f,%.7f\n",p3.x, p3.y);//其實p2的座標與p3一樣
    //澎湖,金門與馬祖基準轉換為WGS84
    trans = ctFactory.createTransform(crsPenghu, WGS84);
    p = new ProjCoordinate(308217.440, 2607766.233);//澎湖縣馬公市文光路48巷4號，也是由TGOS全國門牌地址定位服務找出後再轉成澎湖基準
    p2 = new ProjCoordinate();
    trans.transform(p, p2);
    System.out.printf("馬公市:%.7f,%.7f\n",p2.x, p3.y);
  }
}