DeskriptorTabelle

DeskriptorTabelle is a term used in digital media and data specification to describe a structured collection of metadata descriptors. It refers to a container or sequence that groups individual descriptors, each of which conveys specific metadata about a data element such as a program, a video stream, or a service. The concept is not tied to a single standard but appears in various specifications that require extensible metadata without altering core data formats.

A descriptor itself is a small data unit consisting of a tag that identifies the descriptor type, a length field that specifies the size of the descriptor data, and the descriptor data payload. A DeskriptorTabelle therefore aggregates multiple such descriptors, often associated with a particular context within a transport stream, program metadata, or service information.

In practice, descriptor tables are common in standards used for digital broadcasting and multimedia streaming, such as DVB and MPEG-derived specifications. Descriptor loops are embedded in higher-level tables (for example, program-related tables or service information sections), and each descriptor’s tag value points to a defined format and interpretation. Decoders use the tag to parse and interpret the descriptor data; unknown descriptors can be skipped to maintain compatibility.

Parsing a DeskriptorTabelle typically involves iterating through the table, reading a descriptor_tag (8 bits), a descriptor_length (8 bits), and then descriptor_length bytes of data, applying the appropriate interpretation based on the tag. The system remains extensible through new descriptor definitions without changing existing structures. See also: Descriptor, Descriptor loop, DVB, MPEG.