How to add text to images with the CMYK ColorSpace in .NET 4

Question

I am working on a project that at it's core involves adding text to an image, so as an example given a background image (B) and some text in a specified font, point size and font (A) the two are composited together to produce (C):

The eventual result is to go to print with these images, so the backgrounds are using the CMYK Color Space and I need to keep the whole process within CMYK or the colors look wrong when printed. (note: excellent article on Color Spaces and .NET on CodeProject)

I have tried several different ways of compositing these images together:

• System.Drawing implicitly converts everything to RGB
• System.Windows.Media.Imaging - no compositing methods
• System.XAML/WPF - very promising however RenderTargetBitmap does not work in PixelFormats.Cmyk32 (throws an ArgumentException).

I have looked at but not tried third party commercial components as the prices seem to start high and continue going up:

• Graphics Mill (~US$1800 as of 12/2010)
• Atalasoft DotImage (~US$3300 as of 12/2010)

Is this possible in .NET 4?

Edit: Because someone else might want to do something slightly different and just convert any format that Windows.System.Media.Imaging is able to load to CMYK here is the code I have used:

var bitmapConverter = new FormatConvertedBitmap();
bitmapConverter.BeginInit();
bitmapConverter.Source = sourceImage;
bitmapConverter.DestinationFormat = PixelFormats.Cmyk32;
bitmapConverter.EndInit();

To clarify the above code converts an image source to CMYK32 (no transparency) however if you are using certain classes (namely RenderTargetBitmap passing the above ImageSource will throw an exception).

Answer 1

If you have looked much on SO, you have probably already seen these links. But, just in case, here are some links that I found that might be helpful to you.

Here is a link from here on SO about working with CMYK in .NET:

Convert RGB color to CMYK?

Specifically it mentions using Color Profiles and Windows Color Management APIs.

Here is another SO link:

How to convert CMYK to RGB programmatically in indesign

One answerer mentions that there is not an exact conversion between CMYK and RGB.

Here is a link about compositing two CMYK images without converting to RGB:

The are any CMYK graphics library?

The answerer suggests using a commercial product that he is affiliated with.