Colors can be specified in a number of ways - most commonly in
terms of RGB or CMYK values. These values are literal - RGB values
relate directly to the brightness of the red, green and blue
phosphors on a display - CMYK values relate directly to the amounts
of Cyan, Magenta, Yellow and Black inks applied to a piece of
These literal values do not always equate to the same perceived
color. Monitors vary and an image displayed on one may look quite
different to the same image displayed on another. Similarly a CMYK
value applied with one printer to one type of paper may look quite
different to a CMYK value applied with a different printer to a
different type of paper.
The International Color
Consortium (ICC) provides specifications to allow an
independent definition of color. An ICC color profile is designed
to complement your raw color data. So if you have a CMYK image you
also specify an color profile which tells you more about the
intended destination of the image. This allows you to adjust the
colors for your intended output medium.
In order to maintain flexibility and color fidelity it is
important to preserve both the raw image data and the ICC profile
associated with it. This can only be done if you provide images in
pass-through rather than direct mode.
ABCpdf will accept RGB TIFF, CMYK TIFF, LAB TIFF, Grayscale
JPEG, RGB JPEG and CMYK JPEG direct. This means whatever colors you
pass into ABCpdf will go direct into the PDF without any
modification. Additionally any ICC profile will be preserved and
inserted appropriately so that the colors can be adjusted
accurately for any output.