`line_injections` (project level)¶

The project-wide VITS set, applied to every frame of every section, and the placement policy it is held to. Optional — omit it for a project with no test signals.

This is a sibling of output: and sections:, not a key inside them. Do not confuse it with the per-section line_injections: list, which only names the (unimplemented) vitc injection — see section laserdisc. The disc format is laserdisc.disc_type.

line_injections:
  placement: laserdisc
  vits:
    - vits_type: uk-national
      target_lines: [19, 332]
    - vits_type: vits20
      target_lines: [20, 333]

Keys¶

Key	Type	Required	Values	Default
`placement`	string	No	`standard`, `laserdisc`, `custom`	`standard`
`vits`	list	No	VITS entries (below)	empty

No other key is accepted.

`placement`¶

How strictly the validator constrains each VITS entry's target_lines.

Value	Rule
`standard`	Each VITS type must sit on its broadcast recommended line. Any other line is rejected. `virs` has no single recommended line and is not constrained
`laserdisc`	VITS must sit on the laserdisc VBI lines — PAL 19, 20, 332, 333; NTSC/PAL-M 19, 20, 282, 283. Not available for `SECAM`
`custom`	Any valid VBI line, subject to the overlap and reserved-range rules

standard is used when the key is absent.

Under custom the validator still rejects overlapping lines, and when laserdisc.disc_type is set it still rejects the reserved address-code ranges.

`vits[]`¶

Each entry is a test signal applied to every frame of every section.

Key	Type	Required	Description
`vits_type`	string	Yes	The waveform — see VITS types
`target_lines`	list of int	Yes	1-based frame lines, sequential across the whole frame

Line numbers run across the whole frame, so PAL field 2 lines are 313–625 and NTSC field 2 lines are 263–525. vits20 on line 20 is a field 1 line; on line 333 it is the field 2 equivalent.

Valid vits_type values depend on the video standard; PAL types are rejected in NTSC projects and vice versa. SECAM projects use the PAL types, with a warning that they are rendered with their PAL definitions.

Rules¶

Lines must be within the standard's range (1–625 PAL, 1–525 NTSC/PAL-M).
Every entry needs at least one line, and no line may appear twice, within or between entries.
Under standard placement, each type must be on its recommended line (virs excepted).
Under laserdisc placement, lines must be from that standard's laserdisc VITS set.
When laserdisc.disc_type is set, no VITS may target a reserved address-code line (PAL 6–18, 319–331; NTSC/PAL-M 10–18, 273–281).
When laserdisc.disc_type is set on an NTSC or PAL-M project, a virs entry is required (IEC 60857 §9.1.3).

Why VITS are project-wide¶

A signal path's reference signals do not change halfway through a recording, and on a disc they are a property of the disc rather than of the lead-in or the programme area. Declaring them once removes any way for them to accidentally differ between sections.

There is no section-level vits injection type.

line_injections (project level)¶