SCC — Intentionally Corrupt: Wrong Parity Bytes
An intentionally corrupt SCC file whose first caption is valid but whose second carries byte pairs with the wrong parity. CEA-608 requires odd parity in bit 7 of every byte, and broadcast decoders use it to detect transmission errors. Tests whether a decoder checks parity at all, and whether it drops just the bad caption or the whole file.
Scenarist_SCC V1.0
00:00:01:00 9420 94ae 9470 4e4f 5655 5320 942f
00:00:03:15 9420 94ae 9470 1122 3344 5566 942f
Specifications
- Corruption
- second caption carries bytes with incorrect odd parity
- Valid Captions
- 1
- Standard
- CEA-608 requires odd parity in bit 7
What is a .scc file?
SCC (Scenarist Closed Captions, .scc) is the broadcast interchange format for CEA-608 captions. Each line is an SMPTE timecode followed by pairs of hexadecimal bytes that are the literal 608 control codes and characters, so caption positioning, roll-up versus pop-on style, and italics are all encoded as byte pairs rather than as markup. It is plain ASCII, but it is not human-readable prose.
How to use this file
Use an example .scc file to test broadcast caption ingest, CEA-608 decoders, and conversion to SRT or WebVTT. It is the format that exposes decoders which assume captions are text — parity bits, double-byte control codes, and drop-frame timecodes all have to be handled.
How to use this file for testing
“SCC — Intentionally Corrupt: Wrong Parity Bytes” is a deterministic Novus Examples fixture for Subtitle parsing, Video QA. The same captions across SubRip, WebVTT, ASS/SSA, SBV, and TTML, plus a synced LRC lyric file — for testing subtitle parsers, players, burn-in tools, and format converters against known timings.
Documented properties for this file: SCC · 115 bytes. Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.
Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such — expect parsers to fail loudly rather than silently accept them.
Media fixtures are short and synthetic by design. Prefer waveform or transcript ground truth in the same group when measuring ASR, trim, upscale, or sync tools; do not assume broadcast-quality masters.
Parse the cues and check timings against the documented count; the same captions ship across subtitle formats so you can diff a converter against a known target.
Code examples
<video controls src="clip.mp4">
<track kind="captions" srclang="en" label="English" src="bad-parity.scc" default>
</video>Related files
- assASS — Karaoke Timing and Override TagsAdvanced SubStation Alpha using the features that distinguish it from SubRip: per-syllable \k karaoke timings in centiseconds, a full V4+ style definition with primary and secondary colours, and an \an override that repositions a line. Converting this to SRT necessarily loses all of it, which makes it a good test of whether a converter warns about that or drops it silently.
- csvCSV — Cue Timing ReportPer-cue timings and text metrics for the shared cue list, as a caption QC tool would export them: start, end, duration, line count and character count. Useful as the expected output when testing a caption analyser, and as a quick way to check reading-rate calculations against known values.
- dfxpDFXP — TTML Under Its Other ExtensionTimed text as DFXP — byte-for-byte a TTML document, just under the extension Netflix, Adobe and older captioning tool-chains still use. Same tt root, same head/body/div/p structure, same styling and region attributes. It exists to check that a caption parser dispatches on document content rather than on the file extension: a parser that accepts .ttml but rejects an identical .dfxp is exactly the bug this catches.
- jsonJSON — Caption Cue ListThe same five cues as a plain JSON array with float second timings — the shape most caption pipelines use internally between parsing one format and writing another. Handy as the expected intermediate when testing a converter, since it removes timestamp-formatting differences from the comparison.
- jsonJSON — Timed-Text Suite IndexA machine-readable index of all 67 timed-text, streaming-manifest and ad-signalling fixtures in this wave, with id, format, path and byte size for each. Useful as a work-list when running a parser across the whole suite, and as a manifest to diff against after regenerating.
- lrcLRC — Enhanced Word-Level TimingEnhanced LRC with per-word timings in angle brackets alongside the usual per-line timestamps — the format karaoke and lyric-sync apps consume. Includes the standard metadata tags, an offset field, and a final empty timestamp that clears the display. Simple LRC parsers read only the line timings and silently render the word markers as visible text.
Generated by generation/video_timedtext.py. Free for any use, no attribution required — license.