public Bitmap GetNonRotatedPreview(Size size, Envelope bbox)
{
if (!IsValid)
{
return(null);
}
var geoTrans = (double[])_gt.Clone();
// default transform
if (DoublesAreEqual(geoTrans[0], 0) && DoublesAreEqual(geoTrans[3], 0))
{
geoTrans = new[] { 999.5, 1, 0, 1000.5, 0, -1 }
}
;
Bitmap bitmap = null;
var geoTransform = new GeoTransform(geoTrans);
BitmapData bitmapData = null;
var intVal = new double[BandsNumber];
const int iPixelSize = 3; //Format24bppRgb = byte[b,g,r]
//check if image is in bounding box
if ((bbox.MinX > _envelope.MaxX) || (bbox.MaxX < _envelope.MinX) || (bbox.MaxY < _envelope.MinY) || (bbox.MinY > _envelope.MaxY))
{
return(null);
}
double left = Math.Max(bbox.MinX, _envelope.MinX);
double top = Math.Min(bbox.MaxY, _envelope.MaxY);
double right = Math.Min(bbox.MaxX, _envelope.MaxX);
double bottom = Math.Max(bbox.MinY, _envelope.MinY);
double x1 = Math.Abs(geoTransform.PixelX(left));
double y1 = Math.Abs(geoTransform.PixelY(top));
double imgPixWidth = geoTransform.PixelXwidth(right - left);
double imgPixHeight = geoTransform.PixelYwidth(bottom - top);
//get screen pixels image should fill
double dblBBoxW = bbox.Width;
double dblBBoxtoImgPixX = imgPixWidth / dblBBoxW;
double dblImginMapW = size.Width * dblBBoxtoImgPixX * geoTransform.HorizontalPixelResolution;
double dblBBoxH = bbox.Height;
double dblBBoxtoImgPixY = imgPixHeight / dblBBoxH;
double dblImginMapH = size.Height * dblBBoxtoImgPixY * -geoTransform.VerticalPixelResolution;
if ((DoublesAreEqual(dblImginMapH, 0)) || (DoublesAreEqual(dblImginMapW, 0)))
{
return(null);
}
//// ratios of bounding box to image ground space
//double dblBBoxtoImgX = size.Width / dblBBoxW;
//double dblBBoxtoImgY = size.Height / dblBBoxH;
//double dblLocX = 0, dblLocY = 0;
//// set where to display bitmap in Map
//if (!DoublesAreEqual(bbox.MinX, left))
//{
// if (!DoublesAreEqual(bbox.MaxX, right))
// dblLocX = (_envelope.MinX - bbox.MinX) * dblBBoxtoImgX;
// else
// dblLocX = size.Width - dblImginMapW;
//}
//if (!DoublesAreEqual(bbox.MaxY, top))
//{
// if (!DoublesAreEqual(bbox.MinY, bottom))
// dblLocY = (bbox.MaxY - _envelope.MaxY) * dblBBoxtoImgY;
// else
// dblLocY = size.Height - dblImginMapH;
//}
double bitScalar = GetBitScalar();
try
{
bitmap = new Bitmap((int)Math.Round(dblImginMapW), (int)Math.Round(dblImginMapH), PixelFormat.Format24bppRgb);
bitmapData = bitmap.LockBits(new Rectangle(0, 0, (int)Math.Round(dblImginMapW), (int)Math.Round(dblImginMapH)), ImageLockMode.ReadWrite, bitmap.PixelFormat);
byte cr = NoDataInitColor.R;
byte cg = NoDataInitColor.G;
byte cb = NoDataInitColor.B;
var noDataValues = new double[BandsNumber];
var scales = new double[BandsNumber];
ColorTable colorTable = null;
unsafe
{
var buffer = new double[BandsNumber][];
var band = new Band[BandsNumber];
var ch = new int[BandsNumber];
// get data from image
for (int i = 0; i < BandsNumber; i++)
{
buffer[i] = new double[(int)Math.Round(dblImginMapW) * (int)Math.Round(dblImginMapH)];
band[i] = _ds.GetRasterBand(i + 1);
//get nodata value if present
Int32 hasVal;
band[i].GetNoDataValue(out noDataValues[i], out hasVal);
if (hasVal == 0)
{
noDataValues[i] = Double.NaN;
}
band[i].GetScale(out scales[i], out hasVal);
if (hasVal == 0)
{
scales[i] = 1.0;
}
band[i].ReadRaster((int)Math.Round(x1), (int)Math.Round(y1), (int)Math.Round(imgPixWidth),
(int)Math.Round(imgPixHeight),
buffer[i], (int)Math.Round(dblImginMapW), (int)Math.Round(dblImginMapH),
0, 0);
switch (band[i].GetRasterColorInterpretation())
{
case ColorInterp.GCI_BlueBand:
ch[i] = 0;
break;
case ColorInterp.GCI_GreenBand:
ch[i] = 1;
break;
case ColorInterp.GCI_RedBand:
ch[i] = 2;
break;
case ColorInterp.GCI_Undefined:
if (BandsNumber > 1)
{
ch[i] = 3; // infrared
}
else
{
ch[i] = 4;
if (ColorBlend == null)
{
Double dblMin, dblMax;
band[i].GetMinimum(out dblMin, out hasVal);
if (hasVal == 0)
{
dblMin = Double.NaN;
}
band[i].GetMaximum(out dblMax, out hasVal);
if (hasVal == 0)
{
dblMax = double.NaN;
}
if (Double.IsNaN(dblMin) || Double.IsNaN(dblMax))
{
double dblMean, dblStdDev;
band[i].GetStatistics(0, 1, out dblMin, out dblMax, out dblMean, out dblStdDev);
//double dblRange = dblMax - dblMin;
//dblMin -= 0.1*dblRange;
//dblMax += 0.1*dblRange;
}
var minmax = new float[] { Convert.ToSingle(dblMin), 0.5f * Convert.ToSingle(dblMin + dblMax), Convert.ToSingle(dblMax) };
var colors = new Color[] { Color.Blue, Color.Yellow, Color.Red };
ColorBlend = new ColorBlend(colors, minmax);
}
intVal = new Double[3];
}
break;
case ColorInterp.GCI_GrayIndex:
ch[i] = 0;
break;
case ColorInterp.GCI_PaletteIndex:
colorTable = band[i].GetRasterColorTable();
ch[i] = 5;
intVal = new Double[3];
break;
default:
ch[i] = -1;
break;
}
}
if (BitDepth == 32)
{
ch = new[] { 0, 1, 2 }
}
;
int pIndx = 0;
for (int y = 0; y < Math.Round(dblImginMapH); y++)
{
byte *row = (byte *)bitmapData.Scan0 + (y * bitmapData.Stride);
for (int x = 0; x < Math.Round(dblImginMapW); x++, pIndx++)
{
for (int i = 0; i < BandsNumber; i++)
{
intVal[i] = buffer[i][pIndx] / bitScalar;
Double imageVal = intVal[i] = intVal[i] / bitScalar;
if (ch[i] == 4)
{
if (!DoublesAreEqual(imageVal, noDataValues[i]))
{
Color color = ColorBlend.GetColor(Convert.ToSingle(imageVal));
intVal[0] = color.B;
intVal[1] = color.G;
intVal[2] = color.R;
//intVal[3] = ce.c4;
}
else
{
intVal[0] = cb;
intVal[1] = cg;
intVal[2] = cr;
}
}
else if (ch[i] == 5 && colorTable != null)
{
if (!DoublesAreEqual(imageVal, noDataValues[i]))
{
ColorEntry ce = colorTable.GetColorEntry(Convert.ToInt32(imageVal));
intVal[0] = ce.c3;
intVal[1] = ce.c2;
intVal[2] = ce.c1;
//intVal[3] = ce.c4;
}
else
{
intVal[0] = cb;
intVal[1] = cg;
intVal[2] = cr;
}
}
else
{
if (ColorCorrect)
{
// TODO
// intVal[i] = ApplyColorCorrection(intVal[i], 0, ch[i], 0, 0);
}
}
if (intVal[i] > 255)
{
intVal[i] = 255;
}
}
WritePixel(x, intVal, iPixelSize, ch, row);
}
}
}
}
catch
{
return(null);
}
finally
{
if (bitmapData != null)
{
bitmap.UnlockBits(bitmapData);
}
}
if (TransparentColor != Color.Empty)
{
bitmap.MakeTransparent(TransparentColor);
}
//g.DrawImage(bitmap, new Point((int)Math.Round(dblLocX), (int)Math.Round(dblLocY)));
return(bitmap);
}
#endregion IImage Members
}
