using System;
using System.Drawing;
using System.Drawing.Imaging;
using GDAL;
/**
*
Title: GDAL C# GDALRead example.
* Description: A sample app to read GDAL raster data directly to a C# bitmap.
* @author Tamas Szekeres (szekerest@gmail.com)
* @version 1.0
*/
///
/// A C# based sample to read GDAL raster data directly to a C# bitmap.
///
class GDALReadDirect {
public static void usage()
{
Console.WriteLine("usage: gdalread {GDAL dataset name} {output file name}");
System.Environment.Exit(-1);
}
public static void Main(string[] args)
{
if (args.Length != 2) usage();
// Using early initialization of System.Console
Console.WriteLine("");
try
{
/* -------------------------------------------------------------------- */
/* Register driver(s). */
/* -------------------------------------------------------------------- */
gdal.AllRegister();
/* -------------------------------------------------------------------- */
/* Open dataset. */
/* -------------------------------------------------------------------- */
Dataset ds = gdal.Open( args[0], 0 );
if (ds == null)
{
Console.WriteLine("Can't open " + args[0]);
System.Environment.Exit(-1);
}
Console.WriteLine("Raster dataset parameters:");
Console.WriteLine(" Projection: " + ds.GetProjectionRef());
Console.WriteLine(" RasterCount: " + ds.RasterCount);
Console.WriteLine(" RasterSize (" + ds.RasterXSize + "," + ds.RasterYSize + ")");
/* -------------------------------------------------------------------- */
/* Get driver */
/* -------------------------------------------------------------------- */
Driver drv = ds.GetDriver();
if (drv == null)
{
Console.WriteLine("Can't get driver.");
System.Environment.Exit(-1);
}
Console.WriteLine("Using driver " + drv.LongName);
/* -------------------------------------------------------------------- */
/* Get raster band */
/* -------------------------------------------------------------------- */
for (int iBand = 1; iBand <= ds.RasterCount; iBand++)
{
Band band = ds.GetRasterBand(iBand);
Console.WriteLine("Band " + iBand + " :");
Console.WriteLine(" DataType: " + band.DataType);
Console.WriteLine(" Size (" + band.XSize + "," + band.YSize + ")");
}
/* -------------------------------------------------------------------- */
/* Processing the raster */
/* -------------------------------------------------------------------- */
if (ds.RasterCount < 3)
{
Console.WriteLine("The number of the raster bands is not enough to run this sample");
System.Environment.Exit(-1);
}
SaveBitmapDirect(ds, args[1]);
}
catch (Exception e)
{
Console.WriteLine("Application error: " + e.Message);
}
}
private static void SaveBitmapDirect(Dataset ds, string filename)
{
// Get the GDAL Band objects from the Dataset
Band redBand = ds.GetRasterBand(1);
Band greenBand = ds.GetRasterBand(2);
Band blueBand = ds.GetRasterBand(3);
// Get the width and height of the Dataset
int width = ds.RasterXSize;
int height = ds.RasterYSize;
// Create a Bitmap to store the GDAL image in
Bitmap bitmap = new Bitmap(ds.RasterXSize, ds.RasterYSize, PixelFormat.Format32bppRgb);
DateTime start = DateTime.Now;
// Use GDAL raster reading methods to read the image data directly into the Bitmap
BitmapData bitmapData = bitmap.LockBits(new Rectangle(0, 0, width, height), ImageLockMode.ReadWrite, PixelFormat.Format32bppRgb);
try
{
int stride = bitmapData.Stride;
IntPtr buf = bitmapData.Scan0;
blueBand.ReadRaster(0, 0, width, height, buf, width, height, 1, 4, stride);
greenBand.ReadRaster(0, 0, width, height, new IntPtr(buf.ToInt32()+1), width, height, 1, 4, stride);
redBand.ReadRaster(0, 0, width, height, new IntPtr(buf.ToInt32()+2), width, height, 1, 4, stride);
TimeSpan renderTime = DateTime.Now - start;
Console.WriteLine("SaveBitmapDirect fetch time: " + renderTime.TotalMilliseconds + " ms");
}
finally
{
bitmap.UnlockBits(bitmapData);
}
bitmap.Save(filename);
}
}