Tiff轉換Bitmap處理方法

首先項目中引入BitMiracle.LibTiff.NET的dll

命名空間：

using BitMiracle.LibTiff.Classic;

using System.Runtime.InteropServices;

using System.Windows.Forms;

private static Bitmap TiffToBitmap(string asTiffFile)

  {

   Bitmap bmp = null;

   try

   {

    bmp = (Bitmap)Bitmap.FromFile(asTiffFile);

    return bmp;

   }

   catch

   {

   }

   Tiff tif = Tiff.Open(asTiffFile, "r");

   if (tif == null)

   {

    return null;

   }

   // Find the width and height of the image

   FieldValue[] value = tif.GetField(TiffTag.IMAGEWIDTH);

   int width = value[0].ToInt();

   value = tif.GetField(TiffTag.IMAGELENGTH);

   int height = value[0].ToInt();

   // Read the image into the memory buffer

   int[] raster = new int[height * width];

   if (!tif.ReadRGBAImage(width, height, raster))

   {

    tif.Close();

    tif.Dispose();

    return null;

   }

   tif.Close();

   tif.Dispose();

   // bitmap作成

   bmp = new Bitmap(width, height, PixelFormat.Format24bppRgb);

   Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);

   BitmapData bmpdata = bmp.LockBits(rect, ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);

   byte[] bits = new byte[bmpdata.Stride * bmpdata.Height];

   for (int y = 0; y < bmp.Height; y++)

   {

    int rasterOffset = y * bmp.Width;

    int bitsOffset = (bmp.Height - y - 1) * bmpdata.Stride;

    for (int x = 0; x < bmp.Width; x++)

    {

     int rgba = raster[rasterOffset++];

     bits[bitsOffset++] = (byte)((rgba >> 16) & 0xff);

     bits[bitsOffset++] = (byte)((rgba >> 8) & 0xff);

     bits[bitsOffset++] = (byte)(rgba & 0xff);

    }

   }

   Marshal.Copy(bits, 0, bmpdata.Scan0, bits.Length);

   bmp.UnlockBits(bmpdata);

   return bmp;

  }

使用方法：

Bitmap oBmp = TiffToBitmap(asFileName);