public static int Max(this UnmanagedImage image)
{
if ((image.PixelFormat != PixelFormat.Format8bppIndexed) &&
(image.PixelFormat != PixelFormat.Format16bppGrayScale))
throw new UnsupportedImageFormatException("Only grayscale images are supported");
int width = image.Width;
int height = image.Height;
int stride = image.Stride;
int max = 0;
unsafe
{
if (image.PixelFormat == PixelFormat.Format8bppIndexed)
{
byte* src = (byte*)image.ImageData.ToPointer();
for (int y = 0; y < height; y++)
for (int x = 0; x < width; x++, src++)
if (*src > max) max = *src;
}
else
{
ushort* src = (ushort*)image.ImageData.ToPointer();
for (int y = 0; y < height; y++)
for (int x = 0; x < width; x++, src++)
if (*src > max) max = *src;
}
}
return max;
}
public void MaxTest2()
{
Bitmap image = new byte[, ]
{
{ 5, 2, 7 },
{ 5, 3, 5 },
{ 9, 1, 2 }
}.ToBitmap();
{
Rectangle rectangle = new Rectangle(1, 0, 2, 2);
int expected = 7;
int actual = Tools.Max(image, rectangle);
Assert.AreEqual(expected, actual);
}
{
int expected = 9;
int actual = Tools.Max(image);
Assert.AreEqual(expected, actual);
}
}