Table of Contents

Class DecklinkVANCLines

Namespace
VisioForge.Core.Types.Decklink
Assembly
VisioForge.Core.dll

Defines Vertical Ancillary (VANC) data line numbers for embedding metadata and auxiliary data in the video signal.

public class DecklinkVANCLines

Inheritance

Inherited Members

Remarks

VANC (Vertical Ancillary Data) refers to the non-visible lines in a video signal's vertical blanking interval that can carry additional data such as closed captions, timecode, audio metadata, and other broadcast information. In professional broadcast workflows, VANC data is essential for:

  • Closed captioning (CEA-608/708) for accessibility compliance
  • SMPTE timecode for frame-accurate synchronization
  • Audio metadata including channel assignments and loudness information
  • AFD (Active Format Description) for aspect ratio signaling
  • SCTE-104/35 markers for ad insertion points
  • Teletext data (in PAL regions)
  • V-Chip ratings and parental control data

Different video standards allocate different line numbers for VANC data: - NTSC: Lines 10-20 (525-line system) - PAL: Lines 6-22 (625-line system) - HD formats: Lines vary by standard (e.g., 1080i uses lines 8-20 and 571-583)

This class allows configuration of up to three VANC lines for data insertion or extraction, accommodating various broadcast requirements and standards.

Constructors

DecklinkVANCLines()

Initializes a new instance of the VisioForge.Core.Types.Decklink.DecklinkVANCLines class with all lines disabled.

public DecklinkVANCLines()

Properties

Gets or sets the first VANC line number for data insertion/extraction, or zero to disable.

public ulong Line1 { get; set; }

Property Value

ulong

Remarks

Typically used for primary closed caption data (Line 21 in NTSC, Line 22 in PAL).

Gets or sets the second VANC line number for data insertion/extraction, or zero to disable.

public ulong Line2 { get; set; }

Property Value

ulong

Remarks

Often used for secondary data services or additional caption channels.

Gets or sets the third VANC line number for data insertion/extraction, or zero to disable.

public ulong Line3 { get; set; }

Property Value

ulong

Remarks

Can be used for auxiliary data such as timecode, AFD, or custom metadata.