/// <summary>
/// Extract the depth image and create a mask
/// </summary>
/// <param name="depthInfo">The depth info</param>
/// <param name="y">The current line in the depth and color map</param>
private void WritePlayersMask(DepthImageFrameInfo depthInfo, int y)
{
for (int x = 0; x < depthInfo.Width; ++x)
{
// calculate index into depth array
int depthIndex = x + (y * depthInfo.Width);
short depthPixel = depthInfo.FrameData[depthIndex];
int player = depthPixel & DepthImageFrame.PlayerIndexBitmask;
// if we're tracking a player for the current pixel, do green screen
if (player > 0)
{
// retrieve the depth to color mapping for the current depth pixel
ColorImagePoint colorImagePoint =
_colorCoordinates[depthIndex];
// scale color coordinates to depth resolution
int colorInDepthX = colorImagePoint.X /
depthInfo.ColorToDepthDivisor;
int colorInDepthY = colorImagePoint.Y /
depthInfo.ColorToDepthDivisor;
// make sure the depth pixel maps to a valid point in color space
// check y > 0 and y < depthHeight to make sure we don't write outside of the array
// check x > 0 instead of >= 0 since to fill gaps we set opaque current pixel plus the one to the left
// because of how the sensor works it is more correct to do it this way than to set to the right
if (colorInDepthX > 0 && colorInDepthX < depthInfo.Width &&
colorInDepthY >= 0 &&
colorInDepthY < depthInfo.Height)
{
// calculate index into the green screen pixel array
int greenScreenIndex = colorInDepthX +
(colorInDepthY * depthInfo.Width);
// set opaque
_greenScreenPixelData[greenScreenIndex] =
OpaquePixelValue;
// compensate for depth/color not corresponding exactly by setting the pixel
// to the left to opaque as well
_greenScreenPixelData[greenScreenIndex - 1] =
OpaquePixelValue;
}
}
}
if (_playerOpacityMaskImage == null)
{
_playerOpacityMaskImage = new WriteableBitmap(
depthInfo.Width,
depthInfo.Height,
96,
96,
PixelFormats.Bgra32,
null);
}
_playerOpacityMaskImage.WritePixels(
new Int32Rect(0, 0, depthInfo.Width, depthInfo.Height),
_greenScreenPixelData,
depthInfo.Width * ((_playerOpacityMaskImage.Format.BitsPerPixel + 7) / 8), 0);
}
/// <summary>
/// Do the image composition
/// </summary>
/// <param name="tuple">The depth and color information</param>
/// <param name="image">The background image</param>
private void Merge(Tuple <DepthImageFrameInfo, ColorImageFrameInfo> tuple, BitmapSource image)
{
//No background
if (image == null)
{
return;
}
DepthImageFrameInfo depthInfo = tuple.Item1;
ColorImageFrameInfo colorInfo = tuple.Item2;
//Initiate buffer
if (_greenScreenPixelData.Length != depthInfo.DepthStreamFramePixelDataLength)
{
_greenScreenPixelData = new int[depthInfo.DepthStreamFramePixelDataLength];
}
Array.Clear(_greenScreenPixelData, 0, _greenScreenPixelData.Length);
//Initiate buffer
if (_colorCoordinates.Length != depthInfo.DepthStreamFramePixelDataLength)
{
_colorCoordinates = new ColorImagePoint[depthInfo.DepthStreamFramePixelDataLength];
}
Array.Clear(_colorCoordinates, 0, _colorCoordinates.Length);
_kinectManager.MapDepthFrameToColorFrame(
depthInfo.Format,
depthInfo.FrameData,
colorInfo.Format,
_colorCoordinates);
// loop over each row and column of the depth
for (int y = 0; y < depthInfo.Height; ++y)
{
WritePlayersMask(depthInfo, y);
}
WriteColorPixels(colorInfo);
//Use the bigger image as the size for the resulting picture
int width = Math.Max(colorInfo.Width, image.PixelWidth);
int height = Math.Max(colorInfo.Height, image.PixelHeight);
// create a render target that we'll render our images to
var renderBitmap = new RenderTargetBitmap(width, height,
96.0, 96.0, PixelFormats.Pbgra32);
var imageBrushSource = new ImageBrush
{
ImageSource = image,
Stretch = Stretch.Fill,
TileMode = TileMode.None,
AlignmentX = AlignmentX.Left,
AlignmentY = AlignmentY.Top,
Opacity = 1,
};
var imageBrushMask = new ImageBrush
{
ImageSource = _playerOpacityMaskImage,
Stretch = Stretch.UniformToFill,
TileMode = TileMode.None,
AlignmentX = AlignmentX.Left,
AlignmentY = AlignmentY.Top,
Opacity = 1,
};
var imageBrushPlayer = new ImageBrush
{
ImageSource = _colorBitmap,
Stretch = Stretch.UniformToFill,
TileMode = TileMode.None,
AlignmentX = AlignmentX.Left,
AlignmentY = AlignmentY.Top,
Opacity = 1,
};
var drawingVisual = new DrawingVisual();
//Compose images
using (DrawingContext dc = drawingVisual.RenderOpen())
{
dc.DrawRectangle(imageBrushSource, null /* no pen */,
new Rect(0, 0, width, height));
dc.PushOpacityMask(imageBrushMask);
dc.DrawRectangle(imageBrushPlayer, null /* no pen */,
new Rect(0, 0, width,
height));
}
var result = new RenderTargetBitmap(width,
height,
renderBitmap.DpiX, renderBitmap.DpiY,
renderBitmap.Format);
result.Render(drawingVisual);
//Make it thread context free
result.Freeze();
//broadcast the result
_resultBlock.SendAsync(result);
}
