/// <summary>
/// Creates a new ColorProfileViewModel from a given file, but only
/// if the color profile's color space is known by the view model.
/// Note that the lcms2.dll must have been loaded prior to calling
/// this method!
/// </summary>
/// <param name="fileName">Full file name of the ICS color profile.</param>
/// <returns>Instance of ColorProfileViewModel, or null if the color
/// profile has an unknown color space.</returns>
public static ColorProfileViewModel CreateFromFile(string fileName)
{
cmsHProfile h = cmsOpenProfileFromFile(fileName, "r");
ColorProfileViewModel cpvm = null;
if (h != IntPtr.Zero)
{
ColorSpaceSignature c;
try
{
// Only create a view model if we can handle
// the current profile's color space.
// Attempt to convert the CMS color space signature
// to an XL Toolbox ColorSpaceSignature enum value.
// If this fails, cpvm will remain null.
c = cmsGetColorSpace(h);
ColorSpace colorSpace = c.ToColorSpace();
cpvm = new ColorProfileViewModel(fileName);
cpvm.ColorSpace = colorSpace;
}
catch (NotImplementedException)
{
// NO-OP
}
finally
{
cmsCloseProfile(h);
}
}
return(cpvm);
}
/// <summary>
/// Transforms the pixels of a FreeImageBitmap using a standard color profile
/// for the bitmap's color space and the current color profile.
/// </summary>
/// <param name="freeImageBitmap">FreeImageBitmap whose pixels to convert.</param>
/// <remarks>
/// Since Excel does not support color management at all, conversions are done
/// using standard color profiles that LittleCMS provides.
/// </remarks>
public void TransformFromStandardProfile(FreeImageAPI.FreeImageBitmap freeImageBitmap)
{
cmsHProfile standardProfile = CreateStandardProfile(freeImageBitmap);
if (standardProfile == cmsHProfile.Zero)
{
throw new InvalidOperationException(
"Unable to create standard profile for " + freeImageBitmap.ColorType.ToString());
}
cmsHProfile targetProfile = cmsOpenProfileFromFile(GetPathFromName(), "r");
if (targetProfile == cmsHProfile.Zero)
{
throw new InvalidOperationException(
"Unable to open desired color profile: " + Name);
}
// Create transform with perceptual intent (0) and no special options (0)
cmsHTransform t = cmsCreateTransform(
standardProfile, Lcms.Formatters.TYPE_BGRA_8,
targetProfile, GetLcmsPixelFormat(ColorSpace),
0, 0);
if (t == cmsHTransform.Zero)
{
throw new InvalidOperationException("Unable to create CMS transform.");
}
UInt32 numPixels = (UInt32)freeImageBitmap.Size.Width * (UInt32)freeImageBitmap.Size.Height;
cmsDoTransform(t, freeImageBitmap.Bits, freeImageBitmap.Bits, numPixels);
freeImageBitmap.CreateICCProfile(GetIccBytes());
cmsDeleteTransform(t);
cmsCloseProfile(standardProfile);
cmsCloseProfile(targetProfile);
}
private static extern cmsHTransform cmsCreateTransform(
cmsHProfile Input, cmsUInt32Number InputFormat,
cmsHProfile Output, cmsUInt32Number OutputFormat,
cmsUInt32Number Intent, cmsUInt32Number dwFlags);
private static extern ColorSpaceSignature cmsGetColorSpace(cmsHProfile hProfile);
private static extern cmsBool cmsCloseProfile(cmsHProfile hProfile);
