Unique identifying code is vitally important in a variety of fields, whether to prevent theft or, in the case of media, for example, copyright infringement. The watermark that is embedded into content after its point of creation has to be permanent, imperceptible, standardize-able and constant -- capable of withstanding changes or modifications in that content over time. According to the Asset Identification Primer, current digital watermarking methods allow for images to be altered without losing the ability to extract and read the watermark.
The definitions below offer insight into the basics of watermarking as a generic term for media. In the following weeks we will examine Ad Codes and Program Codes. Both are specific forms of Watermarking as it pertains to media and Set-Top-Box data measurement requirements.
See also: Watermark
CIMM DEFINITION : The process of embedding information into a digital signal in a way that is difficult to remove. The signal may be audio, pictures or video, for example. If the signal is copied, then the information is also carried in the copy, so it prevents copyright infringement. A signal may carry several different watermarks at the same time.
See also: Ad-ID, Metadata, Program Code, Digital Watermarking
CIMM DEFINITION : An element or a specific identifier that is added to content to prevent copyright infringement. This code is embedded in the signal.
Note: According to the Asset ID Primer, there are two types of watermarking: 1. Audio Watermarking, which hides information in an audio file, with that information audible to the listener or affecting the audio quality of the original file; and 2. Video Watermarking, which is an indelible pattern embedded in video content that is imperceptible to the eye but can also be deliberately visible.
Please refer to the CIMM Lexicon online at http://www.cimm-us.org/lexicon.htm for additional information on these and other terms.