A Glossary of Terms

For users of the Digimarc Online Services Portal to enable interactive printed images.

As with most specializations, terms and acronyms are often borrowed or created, leaving us with modified meanings for commonly used terms. Much of the terminology that is used for watermarking printed materials comes from print production with minor, if any, modifications. That being said, not everyone has a printing background, and some borrowed terms might need clarification due to these expanded definitions.

Digimarc Barcode Manager - Digimarc Barcode Manager - the service has 2 functions:

• Provides a simple database to manage your projects, services, and payoffs.
  • Project - Folders used by the OSP to organize your services for a particular project such as "Our June issue recipes" or "My client's local scavenger hunt".
  • Services - This is a record that has a description of what is to be watermarked and the payoff response for that watermark.
  • Payoffs - This is what the person using a watermark reader application will see. Payoffs are usually URLs that connect to a web link that can be a recipe, video, coupon or any mobile engagement that is considered rewarding. It's extremely important that these payoffs are highly valuable so that your customer will want to re-engage and/or share with others. Weak payoffs result in users opting out of future scans, or uninstalling scanning software.

• Provides image and audio watermarking tools.
  • Watermarking or Embedding - Mostly interchangeable when referring to Digimarc's process for imperceptibly modifying an image or audio data file. These modifications allow a scanning device (your mobile phone, etc.) to read the watermark when it is presented as analog output: printed, displayed or played over speakers.
  • Read - The process an application does when it detects, decodes and provides a response to a watermarked file.
  • MRC - File extension and general term for files that are used by the Photoshop plug-in embedder. The MRC file is loaded into the Mobile Watermark Embedder filter (AKA the embedder plug-in) in Photoshop and provides the data for a watermarked file to link to your service and the payoff on the OSP.

• DPI/PPI - Dots per inch for analog (printers) devices and pixels per inch for digital devices (displays and digital cameras). This is the resolution that a device or a bitmapped (digital) image uses when it is reproduced.
  • For watermarking, images that are 300dpi at the size they are printing is recommended.
• LS - Line screen, used by a printing press for printing color images. Line screens allow color printing plates to place process inks close together in a controlled pattern when reproducing a color image.
  • Traditional LS screening can be used for a general characterization of the quality of printing, e.g. 65-85ls are used for newsprint and have a course image quality, higher LS usually offer better image quality; a coffee table book can be 200ls or greater.
• FM - Frequency modulated screening (often referred to as stochastic) creates dithering patterns used to reproduce color images for ink jets or some commercial presses.
  • Typically stochastic, and hybrids using FM screening with traditional LS, are indications of a fairly high quality image reproduction.
  • The direct effect color screening has on the watermark is its relationship to image reproduction. Watermarking works with newsprint or for coffee table books, it's just a matter of adjusting the watermarking strength for the quality of the printing (image reproduction).
• Color Mode - Color model or color space, usually considered interchangeable, is the image in color and for watermarking in either RGB or CMYK.
  • The RGB color model uses light to create colors, your computer monitor display is RGB.
  • CMYK - 4C process - uses pigments to produce colors (4 colors are mixed to generate all colors), most printed color images are CMYK.
  • OSP watermarking is optimized for 4C (CMYK) process printing.

Resizing and resample - These are two very different ways to change the size of an image. A previous blog, The Difference Between Resize and Resample, goes into greater detail.