public static FastDirectImage Create(int width, int height, PixelFormat pixelFormat)
{
var newImg = new FastDirectImage();
newImg.PixelFormat = pixelFormat;
newImg.BitPerPixel = Image.GetPixelFormatSize(pixelFormat);
newImg.PixelFormatSize = newImg.BitPerPixel / 8;
// Gör inte såhär för att räkna ut Stride: newImg.Stride = width * newImg.PixelFormatSize;
// Detta då stride för bitmappar måste alignbara med 32 bitar (4 byte). (Antagligen för att förenkla kopiering av rader)
// http://www.tech-archive.net/Archive/DotNet/microsoft.public.dotnet.framework.drawing/2006-09/msg00057.html
//In your loop, you copy the pixels one scanline at a time and take into
//consideration the amount of padding that occurs due to memory alignment.
newImg.Stride = ((width * newImg.BitPerPixel + 31) & ~31) >> 3;
newImg.Padding = newImg.Stride - (((width * newImg.BitPerPixel) + 7) / 8);
newImg.bits = new byte[newImg.Stride * height];
newImg.handle = GCHandle.Alloc(newImg.bits, GCHandleType.Pinned);
IntPtr pointer = Marshal.UnsafeAddrOfPinnedArrayElement(newImg.bits, 0);
newImg.NativeBitmap = new Bitmap(width, height, newImg.Stride, pixelFormat, pointer);
// Kan kanske vara något för
//var b = newImg.NativeBitmap.LockBits(new Rectangle(0, 0, newImg.NativeBitmap.Width, newImg.NativeBitmap.Height), ImageLockMode.ReadWrite, pixelFormat);
return newImg;
}
public double[] CreateVerticalHistogram(FastDirectImage img)
{
Stopwatch totalTime = Stopwatch.StartNew();
int width = img.Width;
int height = img.Height;
double[] vhist = new double[height];
for (int y = 0; y < height; y++)
{
double sum = 0;
for (int x = 0; x < width; x++)
sum += img.GetPixel(x, y).GetBrightness();
vhist[y] = sum / width;
}
Debug.WriteLine("HistogramCreator:CreateVerticalHistogram Total time: " + totalTime.Elapsed.TotalSeconds.ToString());
return vhist;
}
public static FastGrayScaleImage FromImage(FastDirectImage img)
{
int width = img.Width;
int height = img.Height;
var result = new FastGrayScaleImage(width, height);
int oIndex = -img.Padding;
int dIndex = -result.image.Padding;
int dIndexLineLenght = result.image.Stride - result.image.Padding;
int dIndexEoi = (height * result.image.Stride) - result.image.Padding;
int dIndexNextLine;
int r;
int g;
int b;
int imgPixelFormatSize = img.PixelFormatSize;
int resultPixelFormatSize = result.image.PixelFormatSize;
byte[] imgBytes = img.Bits;
byte[] resultBytes = result.image.Bits;
while (dIndex < dIndexEoi)
{
oIndex += img.Padding;
dIndex += result.image.Padding;
dIndexNextLine = dIndex + dIndexLineLenght;
while(dIndex < dIndexNextLine)
{
r = imgBytes[oIndex];
g = imgBytes[oIndex + 1];
b = imgBytes[oIndex + 2];
resultBytes[dIndex] = (byte)((b * 0.11) + (g * 0.59) + (r * 0.3));
oIndex += imgPixelFormatSize;
dIndex += resultPixelFormatSize;
}
}
return result;
}
public FastGrayScaleImage(int width, int height)
{
image = FastDirectImage.Create(width, height, PixelFormat.Format8bppIndexed);
CreateGrayScalePalette(image.NativeBitmap);
}
private void UpdateVerticalHistogram(FastDirectImage image)
{
var h = new HistogramCreator();
double[] vhist = h.CreateVerticalHistogram(image);
Bitmap b = new Bitmap(100, image.Height, PixelFormat.Format16bppRgb555);
using (Graphics g = Graphics.FromImage(b))
{
g.FillRectangle(Brushes.Black, 0, 0, b.Width, b.Height);
for (int i = 0; i < vhist.Length; i++)
g.DrawLine(Pens.White, 0, i, (float)vhist[i] * (float)100, i);
g.Flush();
}
verticalHistPictureBox.Image = b;
}
