HEVCSVC

HEVCSVC, also written as HEVC SVC or SHVC, is an extension of the High Efficiency Video Coding (HEVC, H.265) standard that enables scalable video coding. A single HEVCSVC bitstream can be decoded at multiple spatial resolutions, frame rates, and quality levels by extracting the appropriate layers. The base layer provides a basic representation, while one or more enhancement layers add resolution, temporal detail, or quality through hierarchical prediction and inter-layer references. This layered approach allows efficient adaptation to heterogeneous networks and devices without requiring a separate stream for each quality level.

Technical aspects of HEVCSVC center on layered coding. The bitstream is organized into a base layer and one or more enhancement layers, with decoding of enhancement layers depending on the base layer. The scheme supports spatial, temporal, and quality scalability, and uses signaling of layer dependencies and inter-layer prediction structures to enable rate-utility tradeoffs while remaining compatible with decoders that only process the base layer.

Standardization and status: SHVC was developed jointly by ITU-T Video Coding Experts Group (VCEG) and ISO/IEC MPEG as a scalable extension to HEVC. It is defined as part of the HEVC family to support scalable delivery. Adoption has been limited in consumer devices due to increased encoding/decoding complexity and licensing considerations, though there is support in some software, codecs, and broadcast workflows.

Applications and context: HEVCSVC is intended for scenarios requiring delivery of video at multiple qualities from a single stream, such as adaptive streaming over networks with variable bandwidth, broadcast and contribution workflows, and certain conferencing and immersive media use cases. It competes with other scalable or adaptive codecs and with newer codecs that emphasize simplicity or different performance traits.