Digital Color Management: Encoding Solutions, 2nd Edition

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Output Signal Processing

In the preceding chapters, several different methods for encoding color images in terms of numerical values were described. Once images are encoded according to such methods, they can be stored in digital form, edited, manipulated, and interchanged among systems. But the ultimate use of encoded color images is to produce hardcopy or softcopy output images.

Producing high-quality output images from digitally encoded color values involves consideration of many of the same factors that were discussed in regard to the input encoding process itself. There also are other considerations that are unique to output signal processing and output image formation. A full discussion of all the relevant output-specific considerations is beyond the scope of this book. However, there are certain aspects of the output imaging process that need to be discussed here because they directly relate to color encoding and because they will be referred to in later discussions on complete color-managed systems.

Generating output images

Generating output images requires the use of output signal processing, which converts encoded color values to output-device digital code values. These code values control output-device drive signals, which in turn control the amounts of the color-forming elements that make up the output image. For example, in the case of an LCD display, RGB device code values ultimately determine the intensities of displayed red, green, and blue light by controlling ...