c# 读取二进制文件画灰度图

发布网友发布时间：2024-08-07 07:25

共2个回答

热心网友时间：2024-08-17 06:10

搜到了下面的程序段，希望能行
/// <summary>
/// 使用byte[]数据，生成256色灰度 BMP 位图
/// </summary>
/// <param name="originalImageData"></param>
/// <param name="originalWidth"></param>
/// <param name="originalHeight"></param>
/// <returns></returns>
public static Bitmap CreateBitmap(byte[] originalImageData, int originalWidth, int originalHeight)
{
//指定8位格式，即256色
Bitmap resultBitmap = new Bitmap(originalWidth, originalHeight, System.Drawing.Imaging.PixelFormat.Format8bppIndexed);

//将该位图存入内存中
MemoryStream curImageStream = new MemoryStream();
resultBitmap.Save(curImageStream, System.Drawing.Imaging.ImageFormat.Bmp);
curImageStream.Flush();

//由于位图数据需要DWORD对齐（4byte倍数），计算需要补位的个数
int curPadNum = ((originalWidth * 8 + 31) / 32 * 4) - originalWidth;

//最终生成的位图数据大小
int bitmapDataSize = ((originalWidth * 8 + 31) / 32 * 4) * originalHeight;

//数据部分相对文件开始偏移，具体可以参考位图文件格式
int dataOffset = ReadData(curImageStream, 10, 4);

//改变调色板，因为默认的调色板是32位彩色的，需要修改为256色的调色板
int paletteStart = 54;
int paletteEnd = dataOffset;
int color = 0;

for (int i = paletteStart; i < paletteEnd; i += 4)
{
byte[] tempColor = new byte[4];
tempColor[0] = (byte)color;
tempColor[1] = (byte)color;
tempColor[2] = (byte)color;
tempColor[3] = (byte)0;
color++;

curImageStream.Position = i;
curImageStream.Write(tempColor, 0, 4);
}

//最终生成的位图数据，以及大小，高度没有变，宽度需要调整
byte[] destImageData = new byte[bitmapDataSize];
int destWidth = originalWidth + curPadNum;

//生成最终的位图数据，注意的是，位图数据从左到右，从下到上，所以需要颠倒
for (int originalRowIndex = originalHeight - 1; originalRowIndex >= 0; originalRowIndex--)
{
int destRowIndex = originalHeight - originalRowIndex - 1;

for (int dataIndex = 0; dataIndex < originalWidth; dataIndex++)
{
//同时还要注意，新的位图数据的宽度已经变化destWidth，否则会产生错位
destImageData[destRowIndex * destWidth + dataIndex] = originalImageData[originalRowIndex * originalWidth + dataIndex];
}
}

//将流的Position移到数据段
curImageStream.Position = dataOffset;

//将新位图数据写入内存中
curImageStream.Write(destImageData, 0, bitmapDataSize);

curImageStream.Flush();

//将内存中的位图写入Bitmap对象
resultBitmap = new Bitmap(curImageStream);

return resultBitmap;
}

/// <summary>
/// 从内存流中指定位置，读取数据
/// </summary>
/// <param name="curStream"></param>
/// <param name="startPosition"></param>
/// <param name="length"></param>
/// <returns></returns>
public static int ReadData(MemoryStream curStream, int startPosition, int length)
{
int result = -1;

byte[] tempData = new byte[length];
curStream.Position = startPosition;
curStream.Read(tempData, 0, length);
result = BitConverter.ToInt32(tempData, 0);

return result;
}

/// <summary>
/// 向内存流中指定位置，写入数据
/// </summary>
/// <param name="curStream"></param>
/// <param name="startPosition"></param>
/// <param name="length"></param>
/// <param name="value"></param>
public static void WriteData(MemoryStream curStream, int startPosition, int length, int value)
{
curStream.Position = startPosition;
curStream.Write(BitConverter.GetBytes(value), 0, length);
}

热心网友时间：2024-08-17 06:11

要看你的二进制文件是怎么编码的
比如每个数代表什么意思，哪个位置的数字表示图像的长和宽等

================
你试一下是否符合你的要求
/// <summary>
/// 载入灰度图
/// </summary>
/// <param name="pb">目标 PictureBox 对象</param>
/// <param name="data">字节数组</param>
/// <param name="width">图片宽度</param>
/// <param name="height">图片高度</param>
void LoadPicture(PictureBox pb,byte[] data,int width,int height)
{
Bitmap bmp = new Bitmap(width, height);
Graphics gp = Graphics.FromImage(bmp);
gp.Clear(Color.White);
int t = 0;
for (int y = 0; y < height; y++)
{
for (int x = 0; x < width; x++ ,t++)
{
if (t >= data.Length)
{
goto endfor;
}
byte c = data[t];
Color color = Color.FromArgb(c, c, c);
gp.FillRectangle(new SolidBrush(color), x, y, 1, 1);
}
}
endfor:
gp.Save();
pb.Image = bmp;
}