VITS types¶
Every vits_type accepted in the project-level line_injections.vits list.
Valid values depend on the video standard: PAL types are rejected in an NTSC project and vice versa. PAL-M projects use the NTSC catalogue. SECAM projects use the PAL catalogue, and any VITS on a SECAM project produces a warning:
SECAM warning: VITS test signals are rendered with their PAL definitions,
including any PAL-modulated chroma packets.
Line numbers are 1-based and sequential across the whole frame, so PAL field 2 lines are 313–625 and NTSC field 2 lines are 263–525.
PAL¶
vits_type |
Signal | Recommended line | Reference |
|---|---|---|---|
vits17 |
EBU/CCIR primary insertion test signal | 17 (field 1) | EBU/CCIR |
itu-multiburst |
ITU multiburst for PAL systems B, D, G, H, I | 18 (field 1) | ITU-R |
uk-national |
IBA/EBU UK national insertion test signal, PAL-I | 19 (field 1) | IBA/EBU |
vits20 |
IBA/EBU UK ITS-2 chrominance amplitude reference | 20 (field 1) | IBA/EBU |
itu-composite |
ITU PAL composite insertion test signal | 330 (field 2) | ITU-R BT.628 / BT.473 |
itu-combination |
ITU combination insertion test signal for PAL | 331 (field 2) | ITU-R BT.473 |
NTSC and PAL-M¶
vits_type |
Signal | Recommended line | Reference |
|---|---|---|---|
ntc7-composite |
NTC-7 composite insertion test signal | 17 (field 1) | EIA RS-498 / SMPTE RP 168 |
fcc-multiburst |
FCC multi-burst insertion test signal | 18 (field 1) | FCC Part 73 / EIA RS-498 |
ntc7-combination |
NTC-7 combination insertion test signal | 280 (field 2) | EIA RS-498 / SMPTE RP 168 |
fcc-composite |
FCC composite insertion test signal | 281 (field 2) | FCC Part 73 / EIA RS-498 |
virs |
Video Index Reference Signal — format identification and level calibration | 19 / 282 (not enforced) | SMPTE RP 168 / EIA RS-498 |
Placement¶
The placement policy decides which lines are accepted:
standard (default)¶
Each type must sit on its recommended line, as listed above. Any other line is rejected. virs is the exception: it has no single recommended line, so standard placement accepts it on any valid line.
laserdisc¶
VITS must sit on the laserdisc VBI lines, which are clear of the address-code ranges. Not available for SECAM projects.
| Standard | Permitted lines | Reference |
|---|---|---|
| PAL | 19, 20, 332, 333 | IEC 60856 §9.1.3 |
| NTSC / PAL-M | 19, 20, 282, 283 | IEC 60857 §9.1.3, §9.1.4 |
The spec-required sets, which the GUI seeds when you select this policy:
| Standard | Set |
|---|---|
| PAL | uk-national on 19/332, vits20 on 20/333 |
| NTSC / PAL-M | virs on 19/282, ntc7-composite on 20, ntc7-combination on 283 |
custom¶
Any valid VBI line. The overlap and reserved-range rules still apply.
Compatibility with laserdisc codes¶
When laserdisc.disc_type is set, no VITS may target a line in the reserved address-code ranges — PAL 6–18 and 319–331, NTSC/PAL-M 10–18 and 273–281. That rules out most of the broadcast lines.
PAL¶
vits_type |
Line | On a disc |
|---|---|---|
vits17 |
17 | Rejected |
itu-multiburst |
18 | Rejected |
uk-national |
19 | Allowed |
vits20 |
20 | Allowed |
itu-composite |
330 | Rejected |
itu-combination |
331 | Rejected |
NTSC and PAL-M¶
vits_type |
Line | On a disc |
|---|---|---|
ntc7-composite |
17 | Rejected |
fcc-multiburst |
18 | Rejected |
ntc7-combination |
280 | Rejected |
fcc-composite |
281 | Rejected |
virs |
19, 282 | Required |
NTSC discs must carry VIRS
IEC 60857 §9.1.3 makes the Video Index Reference Signal mandatory on NTSC laserdiscs. An NTSC or PAL-M project that sets laserdisc.disc_type and has no virs entry fails validation:
Noise measurement lines¶
Analysis tools measure White SNR from the white reference on PAL frame line 19 or NTSC frame line 20. If a section uses noise_spread_db and no VITS targets that line, videosynth warns that the White SNR target will not be verifiable downstream. See noise.