Audio Processing Notes. Imagine communications Platinum PX-HSR8OMX8O-OBG, Platinum PX-HSR8CMX8C-OBG, Platinum PX-HSRMX-OBG, Platinum PT-FSDMX8O1D-IBG, Platinum PT-FSDX8C1D-IBG, Platinum PT-FSDMXO-IBG, Platinum PT-FSDMX-IBG, Platinum PX-HSR8C2D-OBG, Platinum PX-HSR8O2D-OBG, Platinum PX-HSR16O-OBG

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Platinum™ IP3

Installation and Operation Manual PX-HSRMX-OBG Frame Sync and Mux Output Module

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Audio Swap (on a per mono-channel basis, but based on a predefined list of Swaps)

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Audio Test Tone Generator (Off, 400Hz, 2kHz, 4kHz)

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Dolby-E Header alignment (for Dolby-E data received via TDM only)

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Embedding 4 groups (16 mono channels) of Audio after the Frame/Audio Synchronizer.

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Automatic Audio selection from video source (embedded audio) or associated 16 channels of Audio received via TDM.

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Audio TDM channels if present (i.e. routed from the Audio crosspoint) take precedence over channels de-embedded from the video source.



Fixed mapping of Audio channels received via TDM and the eight SDI streams

(e.g. TDM1-16 -> SDI1, TDM17-32 -> SD).

Audio Processing Notes

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De-embedding: For De-embedding, audio must be embedded synchronously at a sample rate of

48kHz.

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Embedded Dolby-E frames must be properly aligned with the Video frame in order to be transferred from the Frame Synchronizer’s input clock domain into the output clock domain. Proper alignment

(position of guard-band) is important since Dolby-E frames can be dropped or repeated alongside the active video content.



TDMed Audio All Audio channels received from the Audio crosspoint via TDM are assumed to have a

48kHz sample rate and locked to the same Video reference applied to the board.



Automatic Dolby-E header alignment supported for Dolby-E data received via TDM, where Audio data (PCM or non-PCM) is expected to be already synchronous to the reference applied to the board. When receiving Dolby-E data via TDM, alignment with the actual Video data is unknown and it is therefore important to have the Dolby- E data automatically re-aligned prior to muxing it back into the SDI stream.



Sample Rate Conversion is applied to both, de-embedded and Audio TDM data, but only if it is PCM.

The downstream clock for the SRCs will be locked to the applied Video reference. Non-PCM Audio data (such as Dolby-E/D) cannot be sample rate converted.



If Non-PCM Audio originates from the ingested SDI channel ('embedded Audio'), it is transferred from the input clock domain to the output clock domain by dropping or repeating a full frame of non-PCM data, every time the Video Frame Synchronizer reaches its roll-over point.



If Non-PCM Audio is received via TDM, it is expected to be already in the output clock domain and therefore the SRC in the TDM path gets automatically bypassed.