public static CuttedImageInfo GetCuttedImageInfoByPolygonData(UtmPolygon utmPolygon, double[] geoTransform)
{
//utm-easting upperleft point
var xinit = geoTransform[0];
//utm-northing upperleft point
var yinit = geoTransform[3];
//размер пикселя
var xsize = geoTransform[1];
var ysize = geoTransform[5];
var row1 = Convert.ToInt32((utmPolygon.UpperLeft.Northing - yinit) / ysize);
var col1 = Convert.ToInt32((utmPolygon.UpperLeft.Easting - xinit) / xsize);
var row2 = Convert.ToInt32((utmPolygon.LowerRight.Northing - yinit) / ysize);
var col2 = Convert.ToInt32((utmPolygon.LowerRight.Easting - xinit) / xsize);
var colSize = col2 - col1 + 1;
var rowSize = row2 - row1 + 1;
var cuttedImageInfo = new CuttedImageInfo
{
Col = col1,
Row = row1,
Width = colSize,
Height = rowSize
};
return(cuttedImageInfo);
}
public static bool CloudValidation(string[] folders, GeographicPolygon polygon, string resultCloudMaskTifFilename, string resultCloudMaskPngFilename)
{
byte[] cloudMask = null;
int width = 0;
SpatialReference tifProjection = null;
int height = 0;
var utmPolygon = new UtmPolygon();
foreach (var folder in folders)
{
var landsatData = new LandsatDataDescription(folder);
var qaFile = landsatData.ChannelBqa;
using (var ds = Gdal.Open(qaFile, Access.GA_ReadOnly))
{
double[] geotransform = new double[6];
ds.GetGeoTransform(geotransform);
utmPolygon = Helper.ConvertGeographicPolygonToUtm(polygon, ds);
using (var band = ds.GetRasterBand(1))
{
var projectionRef = ds.GetProjectionRef();
tifProjection = new SpatialReference(projectionRef);
var cuttedImageInfo = ClipImageHelper.GetCuttedImageInfoByPolygonData(utmPolygon, geotransform);
cloudMask = cloudMask ?? new byte[cuttedImageInfo.Width * cuttedImageInfo.Height];
cloudMask = GetCloudMaskByBandAndCoordinates(band, cuttedImageInfo, cloudMask);
width = cuttedImageInfo.Width;
height = cuttedImageInfo.Height;
}
}
}
if (cloudMask == null)
{
return(false);
}
double cloudedPointCount = cloudMask.Count(x => x != 0);
var percentOfCloudedPoints = cloudedPointCount / cloudMask.Count();
bool isValidCloudy = percentOfCloudedPoints < 0.14;
tifProjection.ExportToWkt(out var inputShapeSrs);
double[] argin = { polygon.UpperLeft.Latitude, 30, 0, polygon.UpperLeft.Longitude, 0, -30 };
Helper.SaveDataInFile(resultCloudMaskTifFilename, cloudMask, width, height, DataType.GDT_Byte, argin, inputShapeSrs);
DrawLib.DrawMask(cloudMask, width, height, resultCloudMaskPngFilename);
return(isValidCloudy);
}
public static GeographicPolygon ConvertUtmPolygonToGeographic(UtmPolygon utmPolygon, Dataset ds)
{
SpatialReference monUtm = new SpatialReference(ds.GetProjectionRef());
var geoPolygon = new GeographicPolygon();
SpatialReference monGeo = new SpatialReference(ds.GetProjectionRef());
monGeo.ImportFromEPSG(4326);
double[] res = new double[3];
CoordinateTransformation coordTrans = new CoordinateTransformation(monUtm, monGeo);
coordTrans.TransformPoint(res, utmPolygon.UpperLeft.Easting, utmPolygon.UpperLeft.Northing, 0);
geoPolygon.UpperLeft.Longitude = res[0];
geoPolygon.UpperLeft.Latitude = res[1];
coordTrans.TransformPoint(res, utmPolygon.LowerRight.Easting, utmPolygon.LowerRight.Northing, 0);
geoPolygon.LowerRight.Longitude = res[0];
geoPolygon.LowerRight.Latitude = res[1];
return(geoPolygon);
}
