Where does watermark collide?

In signal processing and information security, a digital watermark is a signal imperceptibly embedded in an image, audio, or video file so that it persists through copying and ordinary processing and can later be detected to prove ownership or trace a source. Cox, Miller, and Bloom's Digital watermarking sets out the embedding, detection, and robustness problems of the field. The referent is an embedded, recoverable signal in digital content, named by analogy with the paper watermark but realised as data rather than a thinning of a sheet.[1]

Unit

Not applicable (an embedded signal); robustness measured against attacks

Recovery means

Not applicable

Measured by

By detectability, imperceptibility (e.g. signal-to-noise), and robustness to attacks

In finance, a high-water mark is the highest value an investor's account in a fund has previously reached, used as a threshold in performance-fee contracts: the manager earns an incentive fee only on gains above that prior peak, so losses must be recovered before new fees apply. Goetzmann, Ingersoll, and Ross analyse the value and incentive effects of such high-water-mark contracts. The referent is a contractual accounting threshold, borrowing the flood-level image but measured in account value, unrelated to paper or embedded signals.[2]

Unit

Account value (the prior peak net asset value)

Recovery means

A fund below its high-water mark earns no incentive fee until the prior peak is regained

Measured by

Tracked as the running maximum of account value net of fees