16bpp图像原始文件怎么解析或转化

[jianzhinengwan]

原始文件.dat,每个像素16bit(应该是gray16),300X300，下面的代码没用

string path = "C:\\test.dat";
byte[] byteArray = null;
if (File.Exists(path))
{
byteArray = File.ReadAllBytes(path);
}
BitmapImage item = new BitmapImage();
MemoryStream ms = new MemoryStream(byteArray);


item.BeginInit();
item.StreamSource = ms;
item.CacheOption = BitmapCacheOption.OnLoad;
item.CreateOptions = BitmapCreateOptions.None;
//item.EndInit();
item.Freeze();
ms.Dispose();


JpegBitmapEncoder en = new JpegBitmapEncoder();
en.Frames.Add(BitmapFrame.Create(item));
FileStream fstream = new FileStream("C:\\Users\\Sai\\Desktop\\sj.jpg", 
FileMode.Create, FileAccess.ReadWrite);
en.Save(fstream);
fstream.Close();

[_lee_chong]

	[StructLayoutAttribute(LayoutKind.Sequential, Pack = 1)]
	struct BITMAPFILEHEADER
	{
		public UInt16	bfType;
		public UInt32	bfSize;
		public UInt16	bfReserved1;
		public UInt16	bfReserved2;
		public UInt32	bfOffBits;
	}

	[StructLayoutAttribute(LayoutKind.Sequential, Pack = 1)]
	struct BITMAPINFOHEADER
	{
		public UInt32	biSize;
		public Int32	biWidth;
		public Int32	biHeight;
		public UInt16	biPlanes;
		public UInt16	biBitCount;
		public UInt32	biCompression;
		public UInt32	biSizeImage;
		public Int32	biXPelsPerMeter;
		public Int32	biYPelsPerMeter;
		public UInt32	biClrUsed;
		public UInt32	biClrImportant;
	}

	[StructLayoutAttribute(LayoutKind.Sequential, Pack = 1)]
	struct BITMAPFILE
	{
		public BITMAPFILEHEADER file;
		public BITMAPINFOHEADER info;

	}

		// 保存一个 大小 16*16 颜色格式rgb565 的16bpp原始数据图（纯红色）
		static void saveADemo()
		{
			FileStream fs = new FileStream ("/Users/leendx/Desktop/demo.dat",FileMode.Create);
			byte[] colorBytes = {0xf8,0x00}; // 1个纯红像素

			for (int i = 0; i < 16*16; i++) {
				fs.Write (colorBytes,0,2);
			}
			fs.Close ();
		}
		// 将示例的原始数据转为32位位图
		static void dataTo32BMP()
		{
			FileStream fs = new FileStream ("/Users/leendx/Desktop/demo.dat",FileMode.Open);
			byte[] colorBytes = new byte[16*16*2];
			fs.Read (colorBytes, 0, 16 * 16 * 2);

			byte[] bmpBytes32 = getBGRAFrom16bpp565 (colorBytes);
			saveBMP_bgra ("/Users/leendx/Desktop/demo.bmp",16,16, bmpBytes32);
		}
		// 将16bpp 565原始数据 转换为 32bpp bgra
		static byte[] getBGRAFrom16bpp565(byte[] src)
		{
			List<byte> lstResult = new List<byte>();

			for (int i = 0; i < src.Length; i+=2) {

				byte one = src[i];
				byte two = src[i+1];

				lstResult.Add((byte)(two & 0x1F <<3));				// b
				lstResult.Add((byte)((two >> 5)&(one << 3) <<2));	// g
				lstResult.Add((byte)(one >> 3 << 3));				// r
				lstResult.Add(0xFF);								// a
			}
			return lstResult.ToArray();
		}
		// 保存bgra位图
		static void saveBMP_bgra(string fileName, int width, int height, byte[] data)
		{
			// 写文件头
			uint bitmapFileStructSize = Convert.ToUInt32(Marshal.SizeOf(typeof(BITMAPFILE)));
			uint dataBytes = Convert.ToUInt32(width * height << 2);
			BITMAPFILE bf = new BITMAPFILE();
			bf.file.bfType = 0x4D42;
			bf.file.bfSize =  bitmapFileStructSize + dataBytes;
			bf.file.bfOffBits = bitmapFileStructSize;
			bf.info.biSize = Convert.ToUInt32(Marshal.SizeOf(typeof(BITMAPINFOHEADER)));
			bf.info.biWidth = width;
			bf.info.biHeight = -height;
			bf.info.biPlanes = 1;
			bf.info.biBitCount = 32;
			bf.info.biSizeImage = dataBytes;

			// 获得文件头bytes
			byte[] bmpFileHead = new byte[bitmapFileStructSize];
			IntPtr pHead = Marshal.AllocHGlobal((int)bitmapFileStructSize);
			Marshal.StructureToPtr (bf, pHead, false);

			Marshal.Copy (pHead, bmpFileHead, 0, bmpFileHead.Length);
			Marshal.FreeHGlobal (pHead);

			// 将文件头及图像数据写入文件
			FileStream fs = new FileStream (fileName,FileMode.Create);
			fs.Write(bmpFileHead,0,bmpFileHead.Length);
			fs.Write(data,0,data.Length);
			fs.Close ();
		}
		public static void Main (string[] args)
		{
			saveADemo ();
			dataTo32BMP ();
		}