EMBEDDED INGEST PRE-PROCESSING AUDIO PROCESSING
Synapse External Control and Monitoring A number of Synapse cards can store multiple configurations in on-board presets which can be recalled by either GPI or via Ethernet commands. By employing this functionality the configuration of the pro-processing system could be dynamically controlled by the Ingest/MAM system. This could be used to change the target video format/frame rate or if the surround sound audio was to encoded using Dolby-E for instance. All cards in the Synapse range provide comprehensive status monitoring information to
the user using the Cortex application which is freely available from the Axon website www.axon.tv and follow the links to the software download page. There is a chargeable option for Cortex to add a customised user interfaces, which could be used to give the Ingest operator a tailor-made screen showing all of the essential information about signal status together with only those controls which are thought necessary.
Video Legalisation and Audio Loudness Control The example on the next page shows the combination of a GDL200 and a DLA44 with an optional DBD18 card providing detection of Dolby-E presence and substitution of PCM audio if Dolby-E is not present. The card GDL200 card detects the video standard and selects the appropriate legaliser standard, manual adjustment of video and color levels is available. The de-embedded audio from the GDL200 is placed on (up to) the first 16-channels of the Quad Speed Multiplexing Audio Bus. By positioning the DLA44 card (and DBD18 if required) in the succeeding numbered slots (N+1 etc.) it is possible to configure the cards to select the audio input from the Quad Speed Bus, process it as required and return it to the Bus for other cards to utilise. The diagram shows the de-embedded Dolby-E stream being placed on the Quad Speed Bus,
the DBD18 is configured to route the appropriate signals from the bus through its Dolby-E decoder and then place the 6 decoded audio channels back into the same bus for the DLA44 card make use of. All audio channels are corrected for normalised dialog level by the DLA44 card which can also produce a 5.1 upmix from a source of stereo audio if the native 5.1 is not available. The output of the DLA44 is also placed on a second Quad Speed Multiplexing Audio Bus which returns the outputs of the “Add-on� cards back to the GDL200 where it can be re-embedded into the legalised video stream. All processing latencies can be accounted for in this combination and the appropriate amount of video delay is adjusted in the GDL200 for absolute lipsync.