SDI Interface

Applicable to AIXpressor

The SDI Interface menu contains sub-pages for Status, Setup, the De-Embedder, and the Embedder.


Select Status (A) from the Interfaces > SDI menu.

Displayed information includes:

  • SDI Status (B) - Shows the status of the internal clock as Locked or Unlocked.

  • Video Format (C) - Indicates the video format as SD, HD, 3G, or N/A.

  • Video Standard (D) - Displays the actual decoded standard (e.g., 1080i50), no SDI lock, or TAG last valid.

  • Overview (E) - Graphically shows the status and potential issues within the SDI signal path. For example, If there is no SDI reference present, the input portion of the graphic will turn red.

  • Audio De-Embedder Status (F) - Indicates the format of the de-embedded signal as PCM, Dolby E, Dolby Digital, Dolby Digital Plus, MPEG-4 HE AAC, MPEG-4 AAC, or N/A.

  • VANC Metadata De-Embedder Status (G) - The indicator turns green when the SDID is detected in the stream; the pre-selected stream as established in the de-embedder setup stream is also identified.

  • Audio Embedder Status (H) - Indicates the status of the embedder as follows:

    • AUTO Embedding - A new group will be built.

    • AUTO Replace - The structure of the group from the input is retained and the audio content is simply replaced.

    • Delete - The group from the input is deleted.

    • OFF - The embedder for the group is disabled.

  • VANC Metadata Embedder Status (I) - Shows the status of the embedder as Enabled or Disabled (for details, see the SMPTE ST 2020-2 standard).

  • ARIB STD-B39 Control Data Status (J) - Indicates the status as Available or Not Available along with the Audio Mode; for more information on the ARIB Japanese standard, see "Structure of Inter-Stationary Control Data Conveyed by Ancilliary Data Packets" at

  • Embedder Metadata Errors (K) - Indicates metadata errors including No Show, Overwrite, Overwrite Block, Overflow, and Audio Sync errors plus the status of the test pattern generator.


Select Setup (A) from the Interfaces > SDI menu.

The SDI Bypass section (B) contains two controls:

  • The SDI Relay Bypass, when enabled, de-activates the bypass relay which serves to connect SDI-IN directly to SDI-OUT1 in the event of a power failure. It also disconnects the de-embedder from the SDI input.

  • The SDI Embedder Bypass, when enabled, will pass embedded audio data from the de-embedder directly through to the embedder 1:1, preserving the original Ancillary Data structure.

The Video Delay section (D) sets the video delay in whole frames to compensate for any latency incurred in the audio chain. "0" turns off the delay function.

The Level B Stream Select dropdown in the 3G SDI Mode section (E) allows Stream 1 or Stream 2 to be used for the embedded audio per SMPTE 425M for details should the 3G-SDI signal contain two HD sub-streams.

The Test Pattern Generator section (C) offers a test generator to either check downstream connections during installation or for use when there is an input source failure. It can also be used to move 16 independent audio channels over a single coax cable from point to point.

The Mode menu includes OFF, AUTO (Input Loss), and Always ON.

The Video Format menu sets the generator's desired output format (resolution and frame rate) and whether it displays color bars or a black frame.


Select De-Embedder (A) from the Interfaces > SDI menu.

The HD SDI standard allows for asynchronous audio, which may require the use of an embedded Wordclock, and is critical in applications that synchronize the audio transport from the SDI de-embedder.

The Audio Sync Source section (B) sets the Embedded Wordclock source.

  • Auto - Asychornous audio is automatically sync'd to the Wordclock of De-Embedded Channel 1.

  • DEM1 - Asynchronous audio is manually sync'd to the incoming SDI signal.

The VANC Metadata De-Embedder section (C) enables or disables the metadata de-embedder; when enabled, the Stream Select menu chooses the individual stream source for the metadata (SSID 1 - SSID 9).


Select Embedder (A) from the Interfaces > SDI menu.

The Audio Embedder Section (B) contains the following controls:

  • Delete Existing Data - Choices include ALL, New HANC Structure, and OFF.

  • Each Group, 1 - 4, has its own Embedding Mode menu. Choices include:

    • OFF - Disables embedding altogether.

    • AUTO - Embedding

    • AUTO - Replace Audio

    • Delete

  • The AES Channel Status menu offers a choice of Transparent or Professional.




Audio Mode

Audio / Non-Audio



Frequency Mode


Sample Frequency


Channel Mode

Not Indicated

User Bits


Auxillary Bits

24 Bit

Audio Word Length

Not Indicated

Important - If you generate a new AES channel status, the Audio Mode will automatically be set to Non-Audio ("Other") for both channels if an adjacent pair (1/2, 3/4, etc.) carries compressed audio (such as a Dolby-encoded stream).

VANC Metadata can be embedded using the following controls in the VANC Metadata Embedder Section (C).

  • Enable - Enables and disables the metadata embedder.

  • Delete Existing Metadata - All / OFF.

  • Stream Select - Determines into which stream the metadata is inserted (SSID 1 - SSID 9).

  • Vidoe Line - Selects which line number receives the metadata, which varies depending upon the video standard employed and how many lines are available for data insertion.

Each embedded audio signal can be delayed independently in the Embedder Audio Delay section (D). This feature is useful for maintaining lip sync when if a video delay is used. Values are in milliseconds (ms) with a range of 0 - 340.

Important - When using a Dolby-encoded signal, adjacent pairs must be set to the same delay values to maintain proper data structure.


Select Device (A) from the Interfaces > SDI menu.

The Parameter Version (B) and Firmware Version (C) of the SDI interface are displayed.

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