DC offset

DC offset

DC offset is an offsetting of a signal from zero. The term originated in electronics, where it refers to a direct current voltage, but the concept has been extended to any representation of a waveform. DC offset is the mean amplitude of the waveform; if the mean amplitude is zero, there is no DC offset.

DC offset is usually undesirable. For example, in audio processing, a sound that has DC offset will not be at its loudest possible volume when normalized (because the offset consumes headroom), and this problem can possibly extend to the mix as a whole, since a sound with DC offset and a sound without DC offset will have DC offset when mixed. It may also cause other artifacts depending on what is being done with the signal.

DC offset can be reduced in real-time by a one-pole one-zero high-pass filter. When one already has the entire waveform, subtracting the mean amplitude from each sample will remove the offset. Often, very low frequencies are called "slowly changing DC". While not technically accurate, a highpass filter can remove such a "changing offset" better because its cutoff does not extend to as low a bandwidth as the above method.

External links

* [http://www.harmony-central.com/articles/tips/eq_dc_offset/ DC Offset: The Case of the Missing Headroom]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • offset — [ ɔfsɛt ] n. m. • 1932; mot angl. « report » ♦ Anglic. Techn. Procédé d impression à plat utilisant le report sur caoutchouc. Affiche imprimée en offset. Par appos. Presse offset. Papier offset, utilisé pour l impression en offset. ● offset nom… …   Encyclopédie Universelle

  • Offset binary — Offset binary,[1] also referred to as excess K, is a digital coding scheme where all zero corresponds to the minimal negative value and all one to the maximal positive value. There is no standard for offset binary, but most often the offset K for …   Wikipedia

  • Offset (mémoire) — Offset (informatique) Pour les articles homonymes, voir Offset. Offset est un terme anglais qui en informatique désigne une adresse relative. L offset est une valeur entière représentant le déplacement en mémoire, par rapport à une adresse de… …   Wikipédia en Français

  • Offset Software — Industry Video gaming Founded 2004 Defunct 2010 Headquarters Newport Beach …   Wikipedia

  • Offset (wheel) — Offset (ET): Distance in mm from center (C) of rim to mounting plane (M) The offset of a vehicle s wheel is the distance between the centerline of the wheel and the plane of the hub mounting surface of the wheel. It can thus be either positive or …   Wikipedia

  • offset — off·set 1 / ȯf ˌset/ n: a claim or amount that reduces or balances another claim or amount: set off the creditor s own debt was an offset; also: the reduction or balance achieved by such a claim off·set 2 /ˌȯf set/ vt: to balance, reduce, or… …   Law dictionary

  • Offset Press Inc. — Offset Press Inc. Type Public TSE: OFST1 Industry Printing Founded 1957 …   Wikipedia

  • offset — [ôf′set΄; ] for v., usually [ ôf set′] n. 1. something that is set off, or has sprung or developed, from something else; offshoot; extension; branch; spur 2. anything that balances, counteracts, or compensates for something else; compensation 3.… …   English World dictionary

  • Offset (gears) — Offset is the perpendicular distance between the axes of hypoid gears or offset face gears.In the diagram to the right, (a) and (b) are referred to as having an offset below center , while those in (c) and (d) have an offset above center . In… …   Wikipedia

  • Offset — steht für: Offset (Film), deutsch rumänischer Film aus dem Jahr 2005 im weiteren Sinn für Kompensationsgeschäft (engl. offset für Verrechnung, Gegenbuchung) in der Technik (engl. offset für Regelabweichung, Versatz) ein konstanter, additiver oder …   Deutsch Wikipedia

  • Offset —   [dt. »Versatz«, »Ausgleich«] der, Verfahren zur relativen bzw. indirekten Adressierung, bei der zu einer Basisadresse ein zusätzlicher Wert, der Offset, addiert wird, um die Zieladresse zu erhalten (Segment Offset Adressierung). Das Verfahren… …   Universal-Lexikon

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”