DVD glossary

Eccentricity

Variation in radius of an information track from the true axis of rotation of the disc. May be confused with runout.

ECC

Mathematically determined Error Correction Code specified in the standards that represents data and is recorded with that data to enable limited correction of read errors.

ECMA

European Computer Manufacturers Association, a regional member of ISO headquartered in Geneva, Switzerland that often initiates and issues standards that are precursors of subsequent ISO standards.

EDC

Mathematically determined Error Detection Code specified in the standards that represents data and is recorded with that data to support limited identification of read errors.

Effect Length

Electrical or optical length in the direction of an information track of a physical data feature such as a pit or land.

EFM

Eight-to-Fourteen Modulation used to convert eight data bits to fourteen channel bits prior to recording.

El Torito

Bootable CD specification named for the restaurant where it was initiated.

Enhanced Music CD

Multisession CD-DA and CD-ROM disc specified in Blue Book playable as an audio CD without data-generated static.

Entrance Surface (Readout Surface)

Substrate surface nearest to the optical pickup head where the laser beam enters and, after reflection, exits.

Erasure Byte

Byte containing one or more erroneous bits flagged by error detection for processing in a subsequent operation.

Error Byte

Byte of unknown location containing one or more erroneous bits.

Extent

Set of logical blocks having addressing numbers that form a continuous ascending sequence.

Easter Eggs
Many DVDs contain "hidden features" stored on the disc, which can usually be accessed by some hidden icon on a menu screen. This practice is becoming more and more common, and is even becoming a promotional device for many distributors.

ECC/EDC
Error Correction Code/Error Detection Code. Codes specified in the color book standards and imbedded in DVD data which facilitate the reconstruction of data if read errors occur.

Encode
In the context of digital video, the process of converting the color space of a video clip from RGB to YUV and then compressing it.

Error Correction
A digital circuit that corrects errors during the retrieving/decoding process.