/// <summary>
/// Convert an float image to a squared integral image
/// </summary>
/// <remarks>
/// We skip the last line to keep the original size (better performance)
/// </remarks>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void IntegralSquare(IImage2DFloatA source, IImage2DFloatA dest)
{
if (source == null) throw new ArgumentNullException("source");
if (dest == null) throw new ArgumentNullException("dest");
if ((source.Width > dest.Width) || (source.Height > dest.Height)) throw new ArgumentException("Destination image (" + dest.Width + "x" + dest.Height + ") must have at least the source image width and height but is only " + source.Width + "x" + source.Height);
int heightS = source.Height;
int widthS = source.Width;
int heightD = dest.Height;
int widthD = dest.Width;
float[] sBuf = source.HostBuffer;
float[] dBuf = dest.HostBuffer;
for (int x = 0; x < widthD; x++) dest.HostBuffer[x] = 0; // zero first line
for (int y = 0, a = widthD * heightD; y < a; y += widthD) dest.HostBuffer[y] = 0; // zero first column
int y1IndexS = 0;
int yIndexD = widthD;
int y1IndexD = 0; // last
// for each line
for (int y = 1; y < heightS; y++)
{
// for each pixel
for (int x = 1; x < widthS; x++)
{
float p = sBuf[y1IndexS + x - 1];
dBuf[yIndexD + x] = p * p + dBuf[yIndexD + x - 1] + dBuf[y1IndexD + x] - dBuf[y1IndexD + x - 1];
}
yIndexD += widthD;
y1IndexS += widthS;
y1IndexD += widthD;
}
dest.Normalized = false;
}
/// <summary>
/// Flip image Y coordinate
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void FlipY(IImage2DFloatA source, IImage2DFloatA dest)
{
if (source == null) throw new ArgumentNullException("source");
if (dest == null) throw new ArgumentNullException("dest");
if (source == dest) throw new ArgumentException("Flipping kernel is not designed to run inline therefore source and destination must be different images");
if ((source.Width > dest.Width) || (source.Height > dest.Height)) throw new ArgumentException("Destination image (" + dest.Width + "x" + dest.Height + ") must have at least the same size as the source image (" + source.Width + "x" + source.Height + ")");
var sBuf = source.HostBuffer;
var dBuf = dest.HostBuffer;
int posSource = 0;
int posDest = (source.Height - 1) * dest.Width;
for (int y = 0, h = source.Height; y < h; y++)
{
for (int x = 0, w = source.Width; x < w; x++)
{
float color = sBuf[posSource++];
dBuf[posDest++] = color;
}
posDest -= dest.Width + source.Width;
}
}
/// <summary>
/// GrayScale image
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void GrayScale(IImage2DFloatRgbA source, IImage2DFloatA dest)
{
if (source == null) throw new ArgumentNullException("source");
if (dest == null) throw new ArgumentNullException("dest");
if ((source.Width > dest.Width) || (source.Height > dest.Height)) throw new ArgumentException("Destination image (" + dest.Width + "x" + dest.Height + ") must have at least the same size as the source image (" + source.Width + "x" + source.Height + ")");
int length = source.Width * source.Height;
int pos = 0;
for (int i = 0; i < length; i++)
{
float gray = 0.2989f * source.HostBuffer[pos++] + 0.5870f * source.HostBuffer[pos++] + 0.1140f * source.HostBuffer[pos++];
pos++;
dest.HostBuffer[i] = gray;
}
dest.Normalized = source.Normalized;
}
/// <summary>
/// Extracts a channel of an RGB image
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
/// <param name="offset">offset (0..3)</param>
public void ExtractChannel(IImage2DFloatRgbA source, IImage2DFloatA dest, byte offset)
{
if (source == null) throw new ArgumentNullException("source");
if (dest == null) throw new ArgumentNullException("dest");
if (offset > 3) throw new ArgumentOutOfRangeException("offset", String.Format("offset must be between 0..3 but was {0}", offset));
if ((source.Width > dest.Width) || (source.Height > dest.Height)) throw new ArgumentException("Destination image (" + dest.Width + "x" + dest.Height + ") must have at least the same size as the source image (" + source.Width + "x" + source.Height + ")");
int length = source.Width * source.Height;
int pos = 0;
for (int i = 0; i < length; i++)
for (int j = 0; j < 4; j++)
if (j == offset) dest.HostBuffer[i] = source.HostBuffer[pos++]; else pos++;
dest.Normalized = source.Normalized;
}
/// <summary>
/// Sobel filter image
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void Sobel(IImage2DFloatA source, IImage2DFloatA dest)
{
if (source == null) throw new ArgumentNullException("source");
if (dest == null) throw new ArgumentNullException("dest");
if ((source.Width > dest.Width) || (source.Height > dest.Height)) throw new ArgumentException("Destination image (" + dest.Width + "x" + dest.Height + ") must have at least the same size as the source image (" + source.Width + "x" + source.Height + ")");
// TODO: Sobel filter image
dest.Normalized = source.Normalized;
}
/// <summary>
/// Sets channel of a RGBA image
/// </summary>
/// <param name="source">source image</param>
/// <param name="mask">mask image</param>
/// <param name="dest">destination image</param>
/// <param name="offset">offset (0..3)</param>
public void SetChannel(IImage2DFloatRgbA source, IImage2DFloatA mask, IImage2DFloatRgbA dest, byte offset)
{
if (source == null) throw new ArgumentNullException("source");
if (mask == null) throw new ArgumentNullException("mask");
if (dest == null) throw new ArgumentNullException("dest");
if (offset > 3) throw new ArgumentOutOfRangeException("offset", String.Format("offset must be between 0..3 but was {0}", offset));
if ((source.Width > mask.Width) || (source.Height > mask.Height)) throw new ArgumentException("Image mask (" + dest.Width + "x" + dest.Height + ") must have at least the same size as the source image (" + source.Width + "x" + source.Height + ")");
if ((source.Width > dest.Width) || (source.Height > dest.Height)) throw new ArgumentException("Destination image (" + dest.Width + "x" + dest.Height + ") must have at least the same size as the source image (" + source.Width + "x" + source.Height + ")");
int length = source.Width * source.Height;
int pos = 0;
for (int i = 0; i < length; i++)
for (int j = 0; j < 4; j++)
{
dest.HostBuffer[pos] = (j == offset) ? mask.HostBuffer[i] : source.HostBuffer[pos];
pos++;
}
}
/// <summary>
/// Gets the sum of a rectangular feature in an integral image.
/// </summary>
public static float GetSum(ref HaarRectangle rect, IImage2DFloatA integralImage, int x, int y)
{
return integralImage.GetIntegralSum(x + rect.ScaledX, y + rect.ScaledY, rect.ScaledWidth, rect.ScaledHeight) * rect.ScaledWeight;
}
/// <summary>
/// Gets the sum of the areas of the rectangular features in an integral image.
/// </summary>
public static float GetNodeSum(ref HaarFeatureNode node, IImage2DFloatA integralImage, int x, int y)
{
float sum;
sum = GetSum(ref node.Rect1, integralImage, x, y);
sum += GetSum(ref node.Rect2, integralImage, x, y);
if (node.RectCount == 3) sum += GetSum(ref node.Rect3, integralImage, x, y);
return sum;
}