International Organization for Standardization

Information technology - Coding of audio-visual objects - Part 20: Lightweight Application Scene Representation (LASeR) and Simple Aggregation Format (SAF) AMENDMENT 3: Presentation and Modification of Structured Information (PMSI) - Second Edition
 N ISO/IEC 14496-20 AMD 3

Annotation

This part of ISO/IEC 14496 defines a scene description format (LASeR) and an aggregation format (SAF) respectively suitable for representing and delivering rich-media services to resource-constrained devices such as mobile phones.

LASeR aims at fulfilling all the requirements of rich-media services at the scene description level. LASeR supports

— an optimized set of objects inherited from SVG to describe rich-media scenes,

— a small set of key compatible extensions over SVG,

— the ability to encode and transmit a LASeR stream and then reconstruct SVG content,

— dynamic updating of the scene to achieve a reactive, smooth and continuous service,

— simple yet efficient compression to improve delivery and parsing times, as well as storage size, one of the design goals being to allow both for a direct implementation of the SDL as documented, as well as for a decoder compliant with ISO/IEC 23001-1 to decode the LASeR bitstream,

— an efficient interface with audio and visual streams with frame-accurate synchronization,

— use of any font format, including the OpenType industry standard, and

— easy conversion from other popular rich-media formats in order to leverage existing content and developer communities.