History[ edit ] The origin of the water part of a watermark can be found back when a watermark was something that only existed in paper. Watermarks were first introduced in FabrianoItalyin Traditionally, a watermark was made by impressing a water-coated metal stamp or dandy roll onto the paper during manufacturing. The invention of the dandy roll in by John Marshall revolutionised the watermark process and made it easier for producers to watermark their paper.
Source tracking different recipients get differently watermarked content Broadcast monitoring television news often contains watermarked video from international agencies Video authentication Software crippling on screencasting and video editing software programs, to encourage users to purchase the full version to remove it.
Content management on social networks  Digital watermarking life-cycle phases[ edit ] General digital watermark life-cycle phases with embedding- attacking- and detection and retrieval functions The information to be embedded in a signal is called a digital watermark, although in some contexts the phrase digital watermark means the difference between the watermarked signal and the cover signal.
The signal where the watermark is to be embedded is called the host signal. A watermarking system is usually divided into three distinct steps, embedding, attack, and detection. In embedding, an algorithm accepts the host and the data to be embedded, and produces a watermarked signal. Then the watermarked digital signal is transmitted or stored, usually transmitted to another person.
If this person makes a modification, this is called an attack. While the modification may not be malicious, the term attack arises from copyright protection application, What does watermarked paper mean third parties may attempt to remove the digital watermark through modification.
There are many possible modifications, for example, lossy compression of the data in which resolution is diminishedcropping an image or video, or intentionally adding noise. Detection often called extraction is an algorithm which is applied to the attacked signal to attempt to extract the watermark from it.
If the signal was unmodified during transmission, then the watermark still is present and it may be extracted. In robust digital watermarking applications, the extraction algorithm should be able to produce the watermark correctly, even if the modifications were strong.
In fragile digital watermarking, the extraction algorithm should fail if any change is made to the signal. Classification[ edit ] A digital watermark is called robust with respect to transformations if the embedded information may be detected reliably from the marked signal, even if degraded by any number of transformations.
Typical image degradations are JPEG compression, rotation, cropping, additive noise, and quantization. For video content, temporal modifications and MPEG compression often are added to this list. A digital watermark is called imperceptible if the watermarked content is perceptually equivalent to the original, unwatermarked content.
Robustness[ edit ] A digital watermark is called "fragile" if it fails to be detectable after the slightest modification. Fragile watermarks are commonly used for tamper detection integrity proof.
Modifications to an original work that clearly are noticeable, commonly are not referred to as watermarks, but as generalized barcodes. A digital watermark is called semi-fragile if it resists benign transformations, but fails detection after malignant transformations.
Semi-fragile watermarks commonly are used to detect malignant transformations. A digital watermark is called robust if it resists a designated class of transformations.
Robust watermarks may be used in copy protection applications to carry copy and no access control information. Perceptibility[ edit ] A digital watermark is called imperceptible if the original cover signal and the marked signal are perceptually indistinguishable. A digital watermark is called perceptible if its presence in the marked signal is noticeable e.
This should not be confused with perceptual, that is, watermarking which uses the limitations of human perception to be imperceptible. Capacity[ edit ] The length of the embedded message determines two different main classes of digital watermarking schemes: The message is conceptually zero-bit long and the system is designed in order to detect the presence or the absence of the watermark in the marked object.
This kind of watermarking scheme is usually referred to as zero-bit or presence watermarking schemes. Sometimes, this type of watermarking scheme is called 1-bit watermark, because a 1 denotes the presence and a 0 the absence of a watermark. The message is an n-bit-long stream.Define watermark.
watermark synonyms, watermark pronunciation, watermark translation to mark (paper) with a watermark. wa•ter•mark I will have watermarked. What is Watermarking What is a watermark? Originally a watermark is a more or less transparent image or text that has been applied to a piece of paper, another image to either protect the original image, or to make it harder to copy the item e.g.
money watermarks or stamp watermarks. FAQ-What is a stamp watermark? October 24, October 24, by Lisa. is listed at $6,! Obviously, it’s a good thing to find a stamp with a watermark.
It can mean the difference between an ordinary stamp and a rarity. So then, what is a stamp watermark? Watermarks are designs or patterns that appear in the actual paper of the stamp. Watermarked videos - what does this mean?
"Watermarked or Pixelated Photos or Videos This Hub has been moderated for low-quality or watermarked images/videos. A watermark is a branding embedded in the paper stock. When you hold some paper up to the light, you can see noticeable brand or logo or wordmark that is brighter than the rest of the paper.
This is because that particular part of the paper is thinner than the rest of . A watermark is an identifying image or pattern in paper that appears as various shades of lightness/darkness when viewed by transmitted light (or when viewed by reflected light, atop a dark.