**Force ttml 123.m4s segments to use just one sample(TRUN.samplecount=1)?**

Mp4box writes 1..N samples to a ttml subtitle file (segdur=8s), sometimes it may have just one sometimes `MOOF/TRAF/TRUN.samplecount=3 (dur=1000, dur=4000, dur=3000)` items.

Is it possible to force ttml text lines go to a single sample within a segment file?

```
MP4Box.exe -add sub_eng_gap1.xml:ext=ttml:lang=eng -new temp-sub_eng.mp4
MP4Box.exe -splitx 0:384 temp-sub_eng.mp4 -out temp-sub_eng.mp4
MP4Box.exe -dash 8000 -mem-frags -profile dashavc264:live -bs-switching no -sample-groups-traf -single-traf -subsegs-per-sidx -1 --tfdt64 --tfdt_traf --noroll=yes --btrt=no --truns_first=yes --cmaf=no -segment-name "$RepresentationID$/sub_$Number$$Init=i$" -out "temp-sub_eng.mpd" "temp-sub_eng.mp4:id=sub_eng"
```

See also: https://github.com/gpac/gpac/issues/866 and https://github.com/gpac/gpac/issues/57#issuecomment-78271907

Or is it [NHNTStream](https://concolato.wp.imt.fr/2014/01/27/first-attempt-at-storing-ttml-in-mp4/) only option, I need to preprocess ttml.xml files to NHNT inputs (one per segment splitted by segment timeline + text line times)?

I believe LiveSim2 supports only `one sample per subtitle_123.m4s segment file` at the moment if using my own vod2live test material.
Force ttml 123.m4s segments to use just one sample(TRUN.samplecount=1)?
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Force ttml 123.m4s segments to use just one sample(TRUN.samplecount=1)?
Issue date:

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**Force ttml 123.m4s segments to use just one sample(TRUN.samplecount=1)?**

Mp4box writes 1..N samples to a ttml subtitle file (segdur=8s), sometimes it may have just one sometimes `MOOF/TRAF/TRUN.samplecount=3 (dur=1000, dur=4000, dur=3000)` items.

Is it possible to force ttml text lines go to a single sample within a segment file?

```
MP4Box.exe -add sub_eng_gap1.xml:ext=ttml:lang=eng -new temp-sub_eng.mp4
MP4Box.exe -splitx 0:384 temp-sub_eng.mp4 -out temp-sub_eng.mp4
MP4Box.exe -dash 8000 -mem-frags -profile dashavc264:live -bs-switching no -sample-groups-traf -single-traf -subsegs-per-sidx -1 --tfdt64 --tfdt_traf --noroll=yes --btrt=no --truns_first=yes --cmaf=no -segment-name "$RepresentationID$/sub_$Number$$Init=i$" -out "temp-sub_eng.mpd" "temp-sub_eng.mp4:id=sub_eng"
```

See also: https://github.com/gpac/gpac/issues/866 and https://github.com/gpac/gpac/issues/57#issuecomment-78271907

Or is it [NHNTStream](https://concolato.wp.imt.fr/2014/01/27/first-attempt-at-storing-ttml-in-mp4/) only option, I need to preprocess ttml.xml files to NHNT inputs (one per segment splitted by segment timeline + text line times)?

I believe LiveSim2 supports only `one sample per subtitle_123.m4s segment file` at the moment if using my own vod2live test material.
--- end body ---
