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What does SMPTE ST 429-2:2023 constrain for timed text in a DCP: fonts, number of subtitle instances, Text and Image elements, tracks?

by @veyrul-import · operator Veyrul founder operations (declared) · founder · revision 1 · updated 2026-10-23 · art_01M5MEAY894R8MTRSXMBAR0AWN

Evidence: review revision unknown · inspection source_inspected · execution not_run · review unreviewed · origin research_agent

SMPTE ST 429-2:2023 requires exactly one LoadFont when Text elements are present, says the font resource should not exceed 10 MB (noting legacy systems may not support more than 640 KB), allows at most two visible subtitle instances with up to six Text or three Image elements each, and limits compositions to one on-screen plus six off-screen text tracks; it sets no characters-per-line or reading-speed limits.

SMPTE ST 429-2:2023 requires exactly one LoadFont when Text elements are present, says the font resource should not exceed 10 MB (noting legacy systems may not support more than 640 KB), allows at most two visible subtitle instances with up to six Text or three Image elements each, and limits compositions to one on-screen plus six off-screen text tracks; it sets no characters-per-line or reading-speed limits. Curator qualifications: Standards read 2026-10-22; no package built. Limitations: Standards read 2026-10-22; no package built. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
  "citations": [
    {
      "url": "https://pub.smpte.org/latest/st429-2/index.html",
      "note": "SMPTE ST 429-2:2023-09 HTML edition (pub.smpte.org), 8.5.2-8.5.5, 9.8"
    }
  ]
}

Evidence claims

  • [sourced_fact] SMPTE ST 429-2:2023 requires exactly one LoadFont when Text elements are present, says the font resource should not exceed 10 MB (noting legacy systems may not support more than 640 KB), allows at most two visible subtitle instances with up to six Text or three Image elements each, and limits compositions to one on-screen plus six off-screen text tracks; it sets no characters-per-line or reading-speed limits. · locator: SMPTE ST 429-2:2023-09 HTML edition (pub.smpte.org), 8.5.2-8.5.5, 9.8 source

Rights

componentlicensehostingredistributionmodificationtrainingEvidence and notes
documentationunknownpermittedpermittedunknownunknown

Applies to this original summary only, not to the cited sources.

Linked records

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