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function rgbImage = MonoImageToSRGB(monoImage,xy,SCALE)
% rgbImage = MonoImageToSRGB(monoImage,xy,[SCALE])
%
% Take a single plane image in and convert to an sRGB standard
% color image out. The chromaticity of the output image will
% be at the specify CIE x,y chromaticity value.
%
% Result is a uint8 image scaled into range [0,255].
%
% The value of SCALE is passed on to SRGBGammaCorrect, and
% there determines whether autoscaling is applied to the image.
%
% See MonoImageToSRGBTest.
%
% 6/15/11 dhb, ms Wrote it.
% Set default
if (nargin < 3 || isempty(SCALE))
SCALE = 1;
end
% First step. Project input plane to CIE XYZ tristimulus image
% at specified chromaticity.
XYZ0 = xyYToXYZ([xy ; 1]);
% String out monochrome image values as a single row.
[monoImageCalFormat,nX,nY] = ImageToCalFormat(monoImage);
% Now convert to a 3 by n matrix, where each column is a scaled
% version of the target XYZ0 values
xyzImageUnscaledCalFormat = XYZ0*monoImageCalFormat;
% Convert to sRGB
rgbImagePrimaryCalFormat = XYZToSRGBPrimary(xyzImageUnscaledCalFormat);
% Gamma correct. This scales the result so that the maximum of the
% RGB values comes out at 255. Thus it is not so good for calibrated
% image processing, where we might want to preserve overall intensity
% differences. But for just looking at stuff, it seems about right.
RGBImageCalFormat = uint8(SRGBGammaCorrect(rgbImagePrimaryCalFormat,SCALE));
% Turn it back into an image
rgbImage = CalFormatToImage(RGBImageCalFormat,nX,nY);
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