Cache / Browser-Cache

Browser Cache is a buffer memory of the web browser, in which retrieved resources (e.g. texts or images) are stored on the user's computer (locally) as a copy. If a resource is needed again later, it can be retrieved from the local cache more quickly than if it had to be reloaded from the server via the Internet.



A Calender is a series of hard pressure rollers used to finish or smooth a sheet of material such as paper, textiles, or plastics.

callas Software

callas Software

Schönhauser Allee 6/7
D-10119 Berlin

Telephone: +49 30 443 90 31 0
Fax: +49 30 441 64 02

E-Mail: info@callassoftware.com


The PDF Preflight and Fixups as well as the Impose functionality and the output via APDFL (Adobe PDF Library) are based on the integration of the SDKs pdfToolbox and pdfChip from callas. The Preflight technology in Adobe Acrobat DC was also developed by callas for Adobe.


Chroma is the C component of the LCH color space.

Chroma represents how far out from the center of the color space (radially) a color lies. The farther out the more saturated the color. The "colorfulness" of a sample judged proportional to the brightness of a white reference sample in the same medium and under the same illumination.

Chromatic/Color Separation

The term Chromatic has it's roots from color separations.

All color tones are built up from Process colors (CMY). K is only available as skeleton black (short black). Undercolor Removal (UCR) is only effective in the darker portions of the image.

Figure: Comparison of chromatic vs. achromatic versions of an image.

Figure: Comparison of the chromatic structure versus the achromatic structure.

Figure: Comparison of the chromatic structure versus the achromatic structure - achromatic structure

Color Depth

Also known as "bit depth". Specifies the number of bits used for each pixel to store the color or brightness value of that pixel.

Color Depth / in Bits Number of Colors (2^n)
1 Bit 2 (Black & White)
2 Bit 4
4 Bit
8 Bit
16 Bit
16,7 Million
32 Bit
~4,3 Billion

Color Engine

Method/algorithm for Color Conversion.

See article Background Knowledge.

Color Logic

ColorLogic GmbH

Robberskamp 40
D-48432 Rheine

Telephone: +49 (0)5971 401016-0
Fax: +49 (0)5971 401016-6

E-Mail: info@colorlogic.de


The Color Management in the Workflow is based on ColorLogic's Cross Color-X technology.

The integration includes the color calculator and profiling functions.

Color Space

A Color Space is a specific organization of colors. In combination with physical device profiling, it allows for reproducible representations of color, in both analog and digital representations. In our case this includes the following Color Spaces:

  • Black and White – also known as "bitmap" or "dash". Each pixel is either black (or 0 or "off") and white (or 1 or "on"), there are no nuances between the two colors.
  • Grayscale colloquially referred to as a black-and-white image. Between black and white there are graded grey tones (= half tones). See also Color Depth
  • RGB – The RGB color model is an additive color model in which red, green and blue light are added together in various ways to reproduce a broad array of colors.
  • CMYK – is a subtractive color model, used in color printing, and is also used to describe the printing process itself.
  • LAB – the absolute (mathematical) color space with which the light perceived by the human eye can be imaged.

Color Spaces can vary greatly in a PDF file.

Device Color Space

A Device Color Space is the device-dependent color space, described in numeric values, e.g.: C=20, M=30, Y=100, K=0. The following device color spaces can be found in a PDF file:

  • Device RGB
  • Device CMYK
  • Device Gray

ICC Based Color Space

An ICC-based Color Space is the device-independent color space described in absolute numeric values in LAB, e.g. L=70, a=-40, b=30. The following ICC-based Color Spaces can be found in a PDF file:

  • ICC-based CMYK
  • ICC-based RGB
  • ICC-based grey
  • ICC-based Lab


  1. A utility found on Mac operating systems that allows users to view and manipulate the details of ICC profiles installed on the computer.
  2. The underlying structure within Mac operating systems that coordinates the color between devices.

Command Prompt

As a normal user, you can start the Command Prompt as an Administrator as follows:

Before Windows 10:

In the search window of the (Windows) Start menu, type cmd, right-click Command Prompt in the search results, and then select Run as Administrator.

Windows 10 and later:

Right-click the (Windows) Start menu (Windows icon) and select Command Prompt (Administrator).

Crop Marks

Bleed Marks [1] are small strokes that are found on the untrimmed printed sheet and mark the final format of the printed matter. They give the final processor - bookbinder or operator on the cutting plotter - an indication of where the final product should be trimmed and separated from the bleed.

A cutting mark, also known as a cutting mark, cutting mark or format mark, belongs to the print marks.

Figure 1: A schematic representation of Crop Marks, this example also includes Bleed Marks as well.

Another type of Printing Mark is the Crop Mark [2]. On the untrimmed printed sheet, it marks the area that an operator on the cutting plotter is to use to trim the final product plus the bleed.