lsm/ntwain
1
0
Fork 0
mirror of https://github.com/soukoku/ntwain.git synced 2026-02-25 13:04:07 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

Update image parse code.

Browse Source
This commit is contained in:
soukoku
2015-02-19 22:30:13 -05:00
parent eef0b9db92
commit 9ba2b0d0e0
10 changed files with 284 additions and 182 deletions
Download Patch File Download Diff File Expand all files Collapse all files

138
NTwain/Internals/ImageTools.cs Normal file
View File

@@ -0,0 +1,138 @@
using NTwain.Interop;
using System;
using System.IO;
using System.Runtime.InteropServices;
namespace NTwain.Internals
{
static class ImageTools
{
// this is modified from twain cs sample
// http://sourceforge.net/projects/twainforcsharp/?source=typ_redirect
public static bool IsDib(IntPtr data)
{
// a quick check not guaranteed correct,
// compare first 2 bytes to size of struct (which is also the first field)
var test = Marshal.ReadInt16(data);
// should be 40
return test == BITMAPINFOHEADER.GetByteSize();
}
public static bool IsTiff(IntPtr data)
{
var test = Marshal.ReadInt16(data);
// should be II
return test == 0x4949;
}
public static Stream GetBitmapStream(IntPtr data)
{
var infoHeader = (BITMAPINFOHEADER)Marshal.PtrToStructure(data, typeof(BITMAPINFOHEADER));
if (infoHeader.Validate())
{
var fileHeaderSize = Marshal.SizeOf(typeof(BITMAPFILEHEADER));
var fileHeader = new BITMAPFILEHEADER();
fileHeader.bfType = 0x4D42; // "BM"
fileHeader.bfOffBits = (uint)fileHeaderSize +
infoHeader.biSize +
(infoHeader.biClrUsed * 4);
fileHeader.bfSize = fileHeader.bfOffBits + infoHeader.biSizeImage;
var dataCopy = new byte[fileHeader.bfSize];
// write file header
IntPtr tempPtr = Marshal.AllocHGlobal(fileHeaderSize);
Marshal.StructureToPtr(fileHeader, tempPtr, true);
Marshal.Copy(tempPtr, dataCopy, 0, fileHeaderSize);
Marshal.FreeHGlobal(tempPtr);
// write image
Marshal.Copy(data, dataCopy, fileHeaderSize, (int)fileHeader.bfSize - fileHeaderSize);
return new MemoryStream(dataCopy);
}
return null;
}
public static Stream GetTiffStream(IntPtr data)
{
// Find the size of the image so we can turn it into a memory stream...
var headerSize = Marshal.SizeOf(typeof(TIFFHEADER));
var tagSize = Marshal.SizeOf(typeof(TIFFTAG));
var tiffSize = 0;
var tagPtr = data.ToInt64() + headerSize;
for (int i = 0; i < 999; i++)
{
tagPtr += (tagSize * i);
var tag = (TIFFTAG)Marshal.PtrToStructure((IntPtr)tagPtr, typeof(TIFFTAG));
switch (tag.u16Tag)
{
case 273: // StripOffsets...
case 279: // StripByteCounts...
tiffSize += (int)tag.u32Value;
break;
}
}
if (tiffSize > 0)
{
var dataCopy = new byte[tiffSize];
// is this optimal?
Marshal.Copy(data, dataCopy, 0, tiffSize);
return new MemoryStream(dataCopy);
}
return null;
}
//internal static Bitmap ReadBitmapImage(IntPtr data)
//{
// Bitmap finalImg = null;
// Bitmap tempImg = null;
// try
// {
// var header = (BITMAPINFOHEADER)Marshal.PtrToStructure(data, typeof(BITMAPINFOHEADER));
// if (header.Validate())
// {
// PixelFormat format = header.GetDrawingPixelFormat();
// tempImg = new Bitmap(header.biWidth, Math.Abs(header.biHeight), header.GetStride(), format, header.GetScan0(data));
// ColorPalette pal = header.GetDrawingPalette(data);
// if (pal != null)
// {
// tempImg.Palette = pal;
// }
// float xdpi = header.GetXDpi();
// float ydpi = header.GetYDpi();
// if (xdpi != 0 && ydpi == 0)
// {
// ydpi = xdpi;
// }
// else if (ydpi != 0 && xdpi == 0)
// {
// xdpi = ydpi;
// }
// if (xdpi != 0)
// {
// tempImg.SetResolution(xdpi, ydpi);
// }
// if (header.IsBottomUpImage)
// {
// tempImg.RotateFlip(RotateFlipType.RotateNoneFlipY);
// }
// finalImg = tempImg;
// tempImg = null;
// }
// }
// finally
// {
// if (tempImg != null)
// {
// tempImg.Dispose();
// }
// }
// return finalImg;
//}
}
}