/// <summary>
/// Create color histogram with N bins
/// </summary>
/// <param name="source">image source</param>
/// <param name="histogram">byte buffer (N^3 bytes)</param>
/// <param name="bins">number of bins</param>
/// <param name="startX">start from this X coordinate</param>
/// <param name="startY">start from this Y coordinate</param>
/// <param name="width">width</param>
/// <param name="height">height</param>
public void HistogramN(IImage2DByteRgbA source, uint[] histogram,
byte bins, int startX, int startY = 0, int width = 0, int height = 0)
{
if (source == null) throw new ArgumentNullException("source");
if (histogram == null) throw new ArgumentNullException("histogram");
if (bins < 2) throw new ArgumentException("bins must be at least 2", "bins");
int size = bins * bins * bins;
if (histogram.Length < size) throw new ArgumentException("Buffer size for histogram must be at least " + size + " bytes", "histogram");
if (width == 0) width = source.Width - startX;
if (height == 0) height = source.Height - startY;
if (width < 0) throw new ArgumentOutOfRangeException("width");
if (height < 0) throw new ArgumentOutOfRangeException("height");
for (int i = 0; i < size; i++) histogram[i] = 0;
float div = 256.0f / bins;
int bins2 = bins * bins;
for (int y = startY, yh = startY + height; y < yh; y++)
{
int pos = (y * source.Width + startX) * 4;
for (int x = startX, xw = startX + width; x < xw; x++)
{
byte r = (byte)(source.HostBuffer[pos++] / div);
byte g = (byte)(source.HostBuffer[pos++] / div);
byte b = (byte)(source.HostBuffer[pos++] / div);
pos++;
histogram[r + g * bins + b * bins2]++;
}
}
}
/// <summary>
/// Create color histogram with N bins
/// </summary>
/// <param name="source">image source</param>
/// <param name="histogram">byte buffer (N^3 bytes)</param>
/// <param name="bins">number of bins</param>
public void HistogramN(IImage2DByteRgbA source, uint[] histogram,
byte bins)
{
if (source == null) throw new ArgumentNullException("source");
if (histogram == null) throw new ArgumentNullException("histogram");
int size = bins * bins * bins;
if (histogram.Length < size) throw new ArgumentException("Buffer size for histogram must be at least " + size + " bytes", "histogram");
for (int i = 0; i < size; i++) histogram[i] = 0;
float div = 256f / bins;
int pos = 0;
int bins2 = bins * bins;
for (int i = 0, length = source.Width * source.Height; i < length; i++)
{
byte r = (byte)(source.HostBuffer[pos++] / div);
byte g = (byte)(source.HostBuffer[pos++] / div);
byte b = (byte)(source.HostBuffer[pos++] / div);
pos++;
histogram[r + g * bins + b * bins2]++;
}
}
/// <summary>
/// Create color histogram with N bins
/// </summary>
/// <param name="source">image source</param>
/// <param name="histogram">byte buffer (N^3 bytes)</param>
/// <param name="bins">number of bins</param>
/// <param name="startX">start from this X coordinate</param>
/// <param name="startY">start from this Y coordinate</param>
/// <param name="width">width</param>
/// <param name="height">height</param>
public void HistogramN(IImage2DByteRgbA source, IBuffer<uint> histogram,
byte bins, int startX, int startY = 0, int width = 0, int height = 0)
{
HistogramN(source, histogram.HostBuffer, bins, startX, startY, width, height);
}
/// <summary>
/// GrayScale image
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void GrayScale(IImage2DByteRgbA source, IImage2DByteA 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 * (float)source.HostBuffer[pos++] + 0.5870f * (float)source.HostBuffer[pos++] + 0.1140f * (float)source.HostBuffer[pos++];
pos++;
dest.HostBuffer[i] = (byte)gray;
}
}
/// <summary>
/// Create color histogram with N bins
/// </summary>
/// <param name="source">image source</param>
/// <param name="histogram">byte buffer (N^3 bytes)</param>
/// <param name="bins">number of bins</param>
public void HistogramN(IImage2DByteRgbA source, IBuffer<uint> histogram,
byte bins)
{
HistogramN(source, histogram.HostBuffer, bins);
}
/// <summary>
/// Flip image Y coordinate
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void FlipY(IImage2DByteRgbA source, IImage2DByteRgbA 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 = 4 * (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++)
{
byte color;
color = sBuf[posSource++]; dBuf[posDest++] = color;
color = sBuf[posSource++]; dBuf[posDest++] = color;
color = sBuf[posSource++]; dBuf[posDest++] = color;
color = sBuf[posSource++]; dBuf[posDest++] = color;
}
posDest -= 4 * (dest.Width + source.Width);
}
}
/// <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(IImage2DByteRgbA source, IImage2DByteA 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++;
}
/// <summary>
/// Convert gray byte image to RGB byte image
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void ByteAToByteRgbA(IImage2DByteA source, IImage2DByteRgbA 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.HostBuffer.Length;
int pos = 0;
for (int i = 0; i < length; i++)
{
byte val = source.HostBuffer[i];
dest.HostBuffer[pos++] = val;
dest.HostBuffer[pos++] = val;
dest.HostBuffer[pos++] = val;
dest.HostBuffer[pos++] = 255;
}
}
/// <summary>
/// Sets a constant value to all cells in an image
/// </summary>
/// <param name="image">image</param>
/// <param name="value">value to set</param>
public void SetValue(IImage2DByteRgbA image, uint value)
{
if (image == null) throw new ArgumentNullException("image");
byte r = (byte)((value >> 24) % 256);
byte g = (byte)((value >> 16) % 256);
byte b = (byte)((value >> 8) % 256);
byte a = (byte)((value) % 256);
int length = image.Width * image.Height;
int pos = 0;
for (int i = 0; i < length; i++)
{
image.HostBuffer[pos++] = r;
image.HostBuffer[pos++] = g;
image.HostBuffer[pos++] = b;
image.HostBuffer[pos++] = a;
}
}
/// <summary>
/// RGB to HSL image
/// </summary>
/// <param name="source">image source</param>
/// <param name="dest">image destination</param>
public void RgbToHsl(IImage2DByteRgbA source, IImage2DByteRgbA 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 + ")");
for (int i = 0, j = 0, length = source.HostBuffer.Length; i < length;)
{
Color color = Color.FromArgb((int)source.HostBuffer[i++], (int)source.HostBuffer[i++], (int)source.HostBuffer[i++]);
dest.HostBuffer[j++] = (byte)(color.GetHue() * 255f / 360f);
dest.HostBuffer[j++] = (byte)(color.GetSaturation() * 255f);
dest.HostBuffer[j++] = (byte)(color.GetBrightness() * 255f);
dest.HostBuffer[j++] = source.HostBuffer[i++];
}
}
