Recent developments in video encoding and streaming technology have come together to supply two major tools to optimize the delivery of synchronized video streams across multiple devices.
The first development is the next generation video coding standard HEVC, which offers significant compression efficiency gains over AVC. And the second is MPEG-DASH, which gives key advantages over HLS, in managing adaptive bitrate streaming of synchronized resolutions and profiles across varying network bandwidths. The combination of HEVC and MPEG-DASH supports higher quality video delivery over limited bandwidth networks.
Apple’s HLS ABR standard is in broad use today, but MPEG-DASH is not that new having been standardized before HEVC, and being applied in the distribution of AVC (H.264) content. MPEG-DASH is codec and media format agnostic, and the magic of MPEG-DASH is that it splits content into a collection of file segments, each containing a short section of the content. The MPEG-DASH standard defines guidelines for implementing interoperable adaptive streaming services, and it describes specific media formats for use with the ISO Base Media File Format (e.g., MP4) or MPEG-2 Transport Stream containers, making the integration of HEVC into an MPEG-DASH workflow possible within existing standards.
MPEG-DASH targets OTT delivery and CDNs but is also finding a home in broadcast and MSO/MVPD environments as a replacement for MPEG-2 TS-based workflows. Through the exhaustive descriptions available in the MPD, MPEG-DASH clients can determine which media segments best fit their user’s preferences, device capability, and network conditions, guaranteeing a high-quality viewing experience and support for next-generation video services.
Early in the development of HEVC, Beamr realized the need for true adaptive bitrate (ABR) Multistreaming support in HEVC as a tool for content preparation for multistreaming services. In Version 3.0 of our HEVC encoder SDK, V.265, we introduced several API extensions supporting multistream encoding. This architecture allows for the encoding of a single master source video into multiple, GOP-aligned streams of various resolutions and bitrates with a single encoder instance. Moreover, newly exposed encoder input settings allow for the specification of individual settings and flags for each of the streams.
Supporting multiple streams of varying resolutions, bitrates, and settings from a single source in a single encoder instance, which guarantees GOP alignment and offers computational savings across shared processes, is critical for reliable ABR encoding/transcoding performance. Beamr’s V.265 encoding SDK offers service providers the opportunity to combine the advancements of HEVC coding with the versatility of MPEG-DASH.
This functionality offers two significant advantages for developing a multistreaming workflow. First, the architecture guarantees that the multiple streams generated by the encoder are 100% GOP-aligned, an essential requirement for any multistreaming workflow. Second, it simplifies the encoding process to a single input source and encoder instance, reducing command-and-control and resource management.
Despite the performance savings available from multistreaming as a result of the shared computing resources that can be leveraged, our implementation yields optimally synchronized streams that are nearly impossible to generate with separate encoders. Beamr’s Multistreaming capability positions V.265 as highly unique, a contributing factor to why V.265 is in use by leading OTT service providers who use our solution as the basis for encoding their 4k HDR and 1080p ABR profiles.