Embedding SCC subtitles into an MP4 file without re-encoding

[neilgd]

I'm trying to embed SCC subtitles into an MP4 file without re-encoding.

I've tried ffmpeg and mkv2mp4, but they don't seem to support SCC files (just SRT).

Handbrake and Amazon MediaConvert will do it, but they both re-encode the files.

Any ideas?

Thanks!

[pcspeak]

I do this to add the srt subs as a separate stream.

ffmpeg.exe" -i "My Video.mp4" -sub_charenc ISO-8859-1 -i "My Subs.srt" -map 0:v -map 0:a -map 1 -c:v copy -c:a copy -c:s mov_text -metadata:s:s:0 language=eng "My Video-New.mp4"

Perhaps it'll work with your scc subs.
The .srt format is converted to mov_text as .srt subtitles cannot be added to an mp4 as a separate stream.
The same will apply with scc subs.
There hasn't been any problems for me. The subs still display correctly and can be switched on/off.
If possible, you would be better to change to the mkv format.

Cheers

[usually_quiet]

SCC (Scenarist Closed Captions) files are normally used to add CEA-608 or EIA-608 closed captions to MPEG-2 or H.264 video for broadcast TV, streaming video, professionally authored DVD, or professionally authored Blu-ray. This type of closed captioning is stored in the video's GOP user data. In theory, it is possible to just copy closed caption data into the GOP user data without re-encoding the video but I don't know what programs are available to consumers who want to do that.

[Edit] Unlike most subtitle files, SCC files are apparently not directly readable by humans. According to a document I found on the pixeltools.com website, a Scenarist Closed Captioning (.scc) text file "contains time codes followed by the actual CEA-608 hex code/ byte pairs that will be inserted in the frames at and following the time code. The 7 bit data and control codes include odd parity which makes them not
trivial to interpret."

[neilgd]

I do this to add the srt subs as a separate stream.

ffmpeg.exe" -i "My Video.mp4" -sub_charenc ISO-8859-1 -i "My Subs.srt" -map 0:v -map 0:a -map 1 -c:v copy -c:a copy -c:s mov_text -metadata:s:s:0 language=eng "My Video-New.mp4"

Perhaps it'll work with your scc subs.

Cheers

Unfortunately ffmpeg cannot embed scc files

[neilgd]

SCC (Scenarist Closed Captions) files are normally used to add CEA-608 or EIA-608 closed captions to MPEG-2 or H.264 video for broadcast TV, streaming video, professionally authored DVD, or professionally authored Blu-ray. This type of closed captioning is stored in the video's GOP user data. In theory, it is possible to just copy closed caption data into the GOP user data without re-encoding the video but I don't know what programs are available to consumers who want to do that.

I have found one app that can do it (cc conver from drastic.tv) but at $900 it’s out of my budget

I need to use SCC files because I’m using Amazon MediaLive and it doesn’t support eg srt or webvtt

[usually_quiet]

SCC (Scenarist Closed Captions) files are normally used to add CEA-608 or EIA-608 closed captions to MPEG-2 or H.264 video for broadcast TV, streaming video, professionally authored DVD, or professionally authored Blu-ray. This type of closed captioning is stored in the video's GOP user data. In theory, it is possible to just copy closed caption data into the GOP user data without re-encoding the video but I don't know what programs are available to consumers who want to do that.

I have found one app that can do it (cc conver from drastic.tv) but at $900 it’s out of my budget

I have been interested in EIA-608 closed captions for years. I am not surprised that the ability to add them has remained firmly within the professional realm and out-of-reach for small studios and ordinary consumers.

[ProWo]

I'm trying to embed SCC subtitles into an MP4 file without re-encoding.
I've tried ffmpeg and mkv2mp4, but they don't seem to support SCC files (just SRT).
Handbrake and Amazon MediaConvert will do it, but they both re-encode the files.
Any ideas?
Thanks!

The mp4 container accepts ttxt, webvtt and vobsub only as captions. Scc isn't supported. So it MUST be converted.
Open Subtitle Edit, load your scc and save as srt.
Open clever-FFmpeg-GUI, load your mp4, click main, click multiplex, click Add stream, select the new created srt, click multiplex.
Done.

[neilgd]

I'm trying to embed SCC subtitles into an MP4 file without re-encoding.
I've tried ffmpeg and mkv2mp4, but they don't seem to support SCC files (just SRT).
Handbrake and Amazon MediaConvert will do it, but they both re-encode the files.
Any ideas?
Thanks!

The mp4 container accepts ttxt, webvtt and vobsub only as captions. Scc isn't supported. So it MUST be converted.
Open Subtitle Edit, load your scc and save as srt.
Open clever-FFmpeg-GUI, load your mp4, click main, click multiplex, click Add stream, select the new created srt, click multiplex.
Done.

There’s a commercial tool that does it (see above) so it’s definitely possible.

And I need CEA-608 subtitles so converting to SRT and embedding isn’t an option unfortunately.

[DB83]

I know little about sub-titles but a while ago I was able to download an Amazon Prime video which has cc. The subs could be demuxed from the mp4 - which still gave the option of displaying them if required. The demuxed subs were SRT. And I hardly think the demuxing program actually did any conversion. The program was mp4boxgui which also allows you to mux - another option to what has already beeen offered.
So, surely, it follows that muxed subs are effectively SRT and your are chasing your tail to attempt to mux scc subs.

[usually_quiet]

I'm trying to embed SCC subtitles into an MP4 file without re-encoding.
I've tried ffmpeg and mkv2mp4, but they don't seem to support SCC files (just SRT).
Handbrake and Amazon MediaConvert will do it, but they both re-encode the files.
Any ideas?
Thanks!

The mp4 container accepts ttxt, webvtt and vobsub only as captions. Scc isn't supported. So it MUST be converted.
Open Subtitle Edit, load your scc and save as srt.
Open clever-FFmpeg-GUI, load your mp4, click main, click multiplex, click Add stream, select the new created srt, click multiplex.
Done.

True. However, I have dozens of mp4 files that contain EIA-608 closed captions. These MP4 files came from a streaming video site that hosts material that was broadcast on US TV. Unlike popular subtitle formats, CEA-608 closed captions are not muxed. Instead, they are stored in the video GOP user data.

This type of closed captioning is often created using SCC files as their source and are added to the video stream's GOP user data using professional tools.

[videobruger]

And I hardly think the demuxing program actually did any conversion.

I think it did. When you mux a srt to a video with mp4boxgui the srt is converted to Timed Text. Similar when you demux the Timed Text subtitles are converted to srt. You may check it with MediaInfo.

[DB83]

I stand somewhat corrected. The demuxed subs are still present in the original mp4. My purpose in the demux was to, hopefully, edit these to remove the narrative that cc gives. That purpose was achieved in the demux/edit which then appeared as SRT. However the original subs are refered, as my friend above states, as 'Timed Text - SBLtt'.

So did mp4boxgui convert these to timed text as part of the demux process ?

[ProWo]

You could try Vimeo:
https://vimeo.com/
It seems to accept scc captions.

[videobruger]

So did mp4boxgui convert these to timed text as part of the demux process ?

It converted the Timed Text subtitles in the MP4 file to .SRT during the demuxing. Behind your back. Without your knowledge

[pcspeak]

I do this to add the srt subs as a separate stream.

ffmpeg.exe" -i "My Video.mp4" -sub_charenc ISO-8859-1 -i "My Subs.srt" -map 0:v -map 0:a -map 1 -c:v copy -c:a copy -c:s mov_text -metadata:s:s:0 language=eng "My Video-New.mp4"

Perhaps it'll work with your scc subs.

Cheers

Unfortunately ffmpeg cannot embed scc files

Did you try the one line script?
With my script the srt subtitles are converted to text in the quicktime mov format.
I have no scc subtitles to test. Could you try with scc subtitles and tell me yay or nay?

This seems to say the Quicktime subtitle container is acceptable when embedded in an mp4
https://docs.aws.amazon.com/mediaconvert/latest/ug/captions-support-tables-by-containe...tput-container

Cheers.
EDIT: Forgot to say please.

[Cornucopia]

This seems to say the Quicktime subtitle container is acceptable when embedded in an mp4

It is, because of the lineage of MP4 (the Quicktime MOV file format is the basis for the MP4 file format, so what is native to MOV, such as chapter/text tracks, is often easily acceptable to MP4).


Scott