User Manual


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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: [email protected]

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.


CCITT – short for Comité Consultatif International Télégraphique et Téléphonique – is a lossless compression algorithm defined by the ITU. The best-known methods are CCITT Group 3 (technical designation = CCITT T.4) and CCITT Group 4 (technical designation = CCITT T.6). Both encodings have been developed specifically for the compression of 1-bit image data, not for color and grayscale images and also not for general data. While Group 3 coding was specially designed for analogue data transmission via communication lines (telephony/fax), Group 4 is already optimized for the coding of digital data for transmission.

CCITT contains three different algorithms that have been specially optimized for typewritten and handwritten documents. These are:

  • CCITT Group 3 one-dimensional: This type of coding is quite similar to that of RLE. Here too, "runs" are recognized and their length is coded with the corresponding value. The difference to RLE is that the "Runs" are not self-defined, but the coding of the "runs" is taken from fixed value tables in which typical "Runs" of black and white pixels are stored. These tables are based on statistical surveys (non-adaptive procedure) on the frequency of average "runs" of black and white pixels and are part of the CCITT T.4 specification. As with RLE, each scan line is considered separately in one-dimensional coding.
  • CCITT Group 3 two-dimensional: While one-dimensional coding only takes into account the horizontal "Runs", two-dimensional coding also takes into account the vertical sequences. Only the differences to the previous line are saved or transferred. This means that the coding of a scan line is influenced by the previous line, which in turn can lead to transmission errors when transmitting via telecommunication channels. Two-dimensional coding thus achieves a significantly higher degree of compression by storing the difference values than can ever be achieved by the optimized storage of "Runs".
  • CCITT Group 4 two-dimensional: In practice, CCITT Group 4 coding has already completely replaced two-dimensional Group 3 coding. Group 4 coding is essentially based on exactly two-dimensional Group 3 coding. It differs only in two important points. First of all, the K-factor has been set to infinity. This factor describes how many scan lines are encoded vertically on top of each other. Furthermore, since Group 4 was developed for data encoding on hard disks, parity bits can be neglected as no transmission errors are to be expected. Group 4 coding is more complex and requires a great deal of computer power, which is, however, always available in today's systems.

Summary: CCITT Group 4 encoding provides the best algorithm for compressing 1-bit image data. This type of coding leads to almost no reduction in halftone images.

Technically speaking, CCITT is a lossless, symmetrical and non-adaptive compression method. In PDF, CCITT is addressed via the CCITTFax-Decode-Filter . Parameterization of the filter is provided. It is not often possible to set these in the graphical user interface of graphic, layout and PDF editors.


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


CMYK basiert auf der subtraktive Farbmischung – eine lineare Umkehrung des RGB-Modells. Farben werden aus einer Mischung von Cyan, Magenta und Gelb (Yellow) erzeugt. Die Farbanmutung entsteht dabei durch Reflexion von Licht und dem Fehlen bestimmter Wellenlängenbereiche des ursprünglich ausgesandten Lichts.

Abbildung 1: Schematische Darstellung, wie aus Licht durch Hinzufügen von Filtern der Sekundärfarben, Primärfarben übrig bleiben.

Da jedes Material, auf das Licht trifft, einen Teil des Lichtes und damit die darin enthaltene Wellenlängen absorbiert, gelangt ein spektral verändertes Signal zum Auge. Schluckt eine Oberfläche den roten Teil des Spektrums, werden nur grüne und blaue Teile reflektiert. Die Mischung aus Grün und Blau ist Cyan, das Auge sieht also eine Cyan-farbige Oberfläche.

Ein Material, welches alle Bereiche des Spektrums ausfiltert, erscheint als Schwarz. Nicht wie bei Monitoren, die das farbige Licht selber emittieren, werden Farben nach dem CMYK Verfahren durch Übereinanderdruck der subtraktiven Primärfarben erzeugt. Die subtraktiven Farben leben aber auch von Ihrer Beleuchtung.

Abbildung 2: Schematische Darstellung des subtraktiven Farbmodells CMYK

Die Primärfarben in der subtraktiven Farbmischung sind Cyan, Magenta und Yellow. Die Sekundärfarben im subtraktiven Farbmodell sind somit Rot, Grün und Blau. Die Sekundärfarben entstehen dabei aus der Mischung von zwei Primärfarben und der Auslassung der dritten Primärfarbe. Komplementärfarben zu den Primärfarben der subtraktiven Farbmischung CMYK sind:

  • Cyan > Rot
  • Magenta > Grün
  • Yellow > Blau

CMYK in Anwendungen

In Grafik-, Layout-, PDF-Editoren oder auch im Workflow werden CMYK-Werte in Schritten von 0% bis 100% pro Kanal eingegeben. Nachkommastellen werden in der Regel nicht angezeigt, obwohl selbstverständlich diese in der internen Umrechnung entstehen.

Color Books & Grid Charts

The Color Books & Grid Charts tab of the Administration > Settings menu item displays all Templates for Color Books and Grid Charts which are available in the Workflow. The templates differ only in size. After installation, templates for DIN-A4, a 160 mm high template for use on narrow web printers and a DIN-A3 template are available by default.

See link

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: [email protected]

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 Policy

Color Policy : After profiling, a default Color Policy must be assigned for each Substrate so that the Substrate can be applied in the Workflow to Articles, Orders, or Production Jobs.

Color Setup

Doing the Color Setup for a substrate means determining its calibration - the printer prints on the substrate in a linearly defined state - and the Color Setup - the description of the printer's color gamut on the substrate.

See Link

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.

Color Space: Device

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

Color Space: ICC Based

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.

Contract Proof

A Contract Proof is a color-binding and legally binding proof according to ISO 12647-7. The contract proof is currently the highest proof standard with the tightest tolerances and is therefore considered a "contract", i.e. it is the contract between the proof producer and the print shop.

An example for checking and issuing a printing system is the Validation Print Creation certificate by Fogra. Companies that are certified by Fogra for Validation Print Creation are likely to carry the FograCert logo. By entering the certification number on the Fogra website, it is easy to check the standard of the Proof and whether the certification is correct and valid.

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.

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