General description of ESB3019 - the ew-vod2cbm service

The core of the ESB3019 product is ew-vod2cbm. The ew-vod2cbm service provides linear video or audio channels via the Edgeware CBM HTTP interface from playlists of VoD assets.

The benefit of using the CBM interface is that the EW repackager sees the source as an ordinary live channel as a normal Edgeware live channel as would originate from the Catchup Buffer Manager (CBM) and can thereby encrypt and package content in all its usual output formats.

The HTTP interface also allows for running the ew-vod2cbm service on a different machine than the EW repackager ESB3002.

Main concepts

To get an efficient and versatile service, it is essential to prepare content in a stream-lined way so that playlists and other metadata content can be minimal and stitching of content can be done on GoP boundaries with no alignment issues.

The main concepts for such a solution are:

  1. Prepare content in a homogeneous way.
  2. Ingest content using ESB3005 into CMAF/ESF format or use DASH OnDemand assets
  3. Start up the server with or without assets and channels configured
  4. Use CBM HTTP interface for repackager integration
  5. Update the assets, channels, and schedules of the channels dynamically via the REST API.

Step 1 and 2 may be fulfilled by a recording of a live channel. Such a recording can be made using the ew-recorder tool of ESB3005 as described in the ESB3005 user guide.

You can also start with VoD assets. If the VoD asset is already in DASH OnDemand format it may work as it is, but otherwise it needs to be converted to ESF format using the ESB3005 ew-recorder component. If the asset consists of SMIL + mp4 + subtitle files, it can also be ingested using the new ESB3021 ew-vodingest tool. That tool can also ingest a directory containing mp4 and subtitle files without referring to a SMIL file.

Supported codecs and formats

The VoD assets must be in DASH OnDemand or Edgeware’s ESF format. In both cases, the audio and video should be in CMAF track files. For subtitles, the DASH OnDemand ingest uses one complete non-segmented side-car file per language, while ESF uses a CMAF track with wvtt segments

The supported codecs are

  • video: AVC/H.264 and HEVC/H.265
  • audio: AAC-LC, HE-AACv1, HE-AACv2
  • DASH OnDemand subtitles: TTML, WebVTT, SRT, STL
  • ESF subtitles: wvtt