What it checks
A conversion reads the source, applies the transformations you asked for (or the profile applies automatically), writes the destination format, then reads the generated file back and judges it against the profile. What happens between the source and the generated file is reported here: every change made on purpose, and everything the destination format cannot carry (a style, a position, a character, a time). Nothing is dropped silently.
How it is measured
Each code below has a severity:
- error: part of the output is wrong or missing (a subtitle skipped, a time clamped): the conversion fails unless you publish anyway;
- warning: something was simplified, dropped or assumed; the file is delivered;
- info: a change made on purpose, reported for traceability.
Transformations
| Code | Severity | Meaning |
|---|---|---|
NORMALIZE_WHITESPACE |
info | Spaces were normalized (repeated, leading or trailing spaces). |
NORMALIZE_LINE_BREAKS |
info | Empty lines inside subtitles were removed. |
REFLOW |
info | Lines were rebalanced to fit the profile's line length and line count. |
REFLOW_IMPOSSIBLE |
warning | A subtitle cannot fit the line limits without rewriting its text; it was left as is. |
ENSURE_MINIMUM_GAP |
info | Earlier subtitles were shortened to restore the minimum gap. |
GAP_FIX_SHORTENS_BELOW_MINIMUM |
warning | Restoring the gap made a subtitle shorter than the minimum duration. |
GAP_UNFIXABLE |
warning | The gap could not be restored without leaving a subtitle with no duration. |
SORT_SUBTITLES |
info | Subtitles were put back in chronological order. |
REMAP_SDH_COLORS |
info | SDH colours were translated from the source colour code to the destination's. |
SDH_COLOR_UNMAPPED |
warning | A colour has no role in the source SDH colour code and was kept as is. |
FRAME_RATE_CHANGED |
info | Times were rescaled for a frame rate change (speed-up or slow-down). |
EBU-STL
| Code | Severity | Meaning |
|---|---|---|
STL_STYLE_DROPPED |
warning | Italic, underline and bold have no teletext equivalent and were dropped (one report for the file). |
STL_UNSUPPORTED_COLOR |
warning | A text colour outside the teletext palette was replaced by the default colour. |
STL_COLOR_CHANGE_ADDS_SPACE |
warning | A colour change inside a word takes a teletext cell, shown as a space. |
STL_UNMAPPABLE_CHARACTER |
warning | Characters not available in the teletext character set were replaced by ?. |
GSI_UNMAPPABLE_CHARACTER |
warning | A header text field (title, reference…) holds characters outside the code page, replaced by ?. |
STL_LANGUAGE_CODE_UNKNOWN |
warning | The language has no EBU-STL language code; 00 was written. |
STL_ALIGNMENT_DROPPED |
warning | Positioning is disabled by the profile; the subtitle was placed at the bottom centre. |
STL_BEFORE_PROGRAMME_START |
warning | Subtitles start before the programme start timecode; the source probably needs an offset. |
STL_SUBTITLE_ZERO_OMITTED |
warning | The "subtitle zero" (programme identity) was not written: no programme start or no identity to put in it. |
STL_EMPTY_SUBTITLE |
warning | A subtitle with no text was skipped. |
STL_ROWS_OVERFLOW |
error | The subtitle has more lines than fit on the teletext screen. |
STL_TEXT_TOO_LONG |
error | The text does not fit in the blocks of one subtitle; the subtitle was skipped. |
STL_NEGATIVE_TIME |
error | A negative time was clamped to 00:00:00:00. |
STL_TIME_OUT_OF_RANGE |
error | A time beyond 23:59:59 was clamped (EBU-STL hours are 00-23). |
SRT
| Code | Severity | Meaning |
|---|---|---|
SRT_COLOR_DROPPED |
warning | Text colour is not written in SRT (unless the profile enables font colours). |
SRT_ALIGNMENT_DROPPED |
warning | SRT has no positioning; the subtitle is shown at the default place. |
SRT_EMPTY_SUBTITLE |
warning | A subtitle with no text was skipped. |
SRT_NEGATIVE_TIME |
error | A negative time was clamped to 00:00:00,000. |
TTML, EBU-TT, EBU-TT-D, IMSC, iTT, SMPTE-TT
| Code | Severity | Meaning |
|---|---|---|
TTML_ALIGNMENT_DROPPED |
warning | iTT only shows centred text at the top or bottom; the placement was simplified. |
ITT_TOO_MANY_LINES |
error | iTT allows two lines per subtitle. |
TTML_EMPTY_SUBTITLE |
warning | A subtitle with no text was skipped. |
TTML_NEGATIVE_TIME |
error | A negative time was clamped to zero. |
EBUTT_TIME_OUT_OF_RANGE |
error | A time outside 00:00:00:00-23:59:59 was clamped (EBU-TT timecodes). |
EBUTT_DPP_METADATA_OMITTED |
warning | The DPP metadata block was not written: its namespace is not set in the profile. |
EBUTT_DPP_COPYRIGHT_MISSING |
warning | The copyright the DPP requires was not written: it is not set in the profile. |
WebVTT
| Code | Severity | Meaning |
|---|---|---|
VTT_STYLE_DROPPED |
warning | Italic, underline and bold are not allowed by the profile and were dropped. |
VTT_COLOR_DROPPED |
warning | A text colour outside the WebVTT default colour classes was dropped. |
VTT_EMPTY_SUBTITLE |
warning | A subtitle with no text was skipped. |
VTT_NEGATIVE_TIME |
error | A negative time was clamped to 00:00:00.000. |
Delivery
| Code | Severity | Meaning |
|---|---|---|
FILENAME_PATTERN_UNRESOLVED |
warning | The profile's file name pattern needs a value that was not given (a content id, a language…); the default name was used. |
Example
Converting an ASS file whose style is bold into a teletext EBU-STL reports STL_STYLE_DROPPED: Italic/underline/bold styling has no teletext equivalent and was dropped in 246 subtitles (#1, #2, …). The file is delivered: teletext cannot show bold, and the destination expects none.
How to fix
- An error means the output is incomplete or wrong: fix the source (a time, a subtitle too long for the destination) and convert again.
- A warning tells you what the destination could not hold; check that it does not matter for this delivery, or adjust the source or the profile's writer settings (positioning, font colours).
- An info line needs no action: it records what CueNorm changed.