MP4 chapters and data stream

[the_steve_randolph]

Just for grins, I decided to do a small comparison to MKV files. I found an MKV that has chapters, multiple audio tracks, multiple subtitle tracks, and, when I look at it with ffmpeg, it has no data stream. So, I run this command:

ffmpeg -i in.mkv -c copy out.mp4

The result was an MP4 with chapters, one audio track, one subtitle track, and, a data stream. Now, I understand how it didn't convert all of the audio and subtitle tracks because the default stream handling behavior only looks at one audio track, one video track, and, one subtitle track. But, with the MP4 having a data stream, that tells me that ffmpeg's default MP4 encoder processing creates that data stream. Next, I did this command:

ffmpeg -in.mkv -map 0 -c copy out.mp4

This time the conversion kept the chapters, all of the audio tracks, all of the subtitle tracks, and, it has the data stream that we have learned holds the chapter names.

Next, I tried converting (with mapping) the MKV to several other formats, and, these were the results:

AVI - error message related to the last subtitle track
WMV - same error message related to the last subtitle track
MPG - results in a file that VLC shows no chapters, 37 audio tracks, and, 71 subtitle tracks. So, something weird there to investigate at another time.
MOV - error message related to the first subtitle track
FLV - error message related to the first audio track
QT, SWF, MPV, WEBM, M4P, M4V - error message that it could not figure out how to convert to this format

This tells me that this "chapter names in a data stream" seems to be a MP4 thing. Isolating it to MP4 should help resolve why this data stream is happening.

[Selur]

This tells me that this "chapter names in a data stream" seems to be a MP4 thing. Isolating it to MP4 should help resolve why this data stream is happening.

You clearly did not get what '-movflags disable_chpl' was about. "chapter names in a data stream" is an Apple thing, mp4 container works fine without it, FFmpeg is just using some default options which try to make the chapters Apple compatible,... (personally I prefer MP4Box)

Cu Selur

[Budman1]

My own personal experience has been, if you create an mp4 with chapters or subtitles abd chapters using movflags disable_chpl, it plays correctly in every player i can find except VLC. VLC shows as an extra subtitle. I believe its a VLC thing.

[the_steve_randolph]

My own personal experience has been, if you create an mp4 with chapters or subtitles abd chapters using movflags disable_chpl, it plays correctly in every player i can find except VLC. VLC shows as an extra subtitle. I believe its a VLC thing.

I have found that every MP4 with chapters that I create has the chapter names in a data stream. As stated above, I have not found that data stream in other video formats. VLC is the only player I have found that does not seem to process that data stream properly.

An exception to this is that I have run across the rare MP4 that has chapters but no data stream. Perhaps the best approach to understanding/resolving this issue is to determine how that AMP4 was created.

[the_steve_randolph]

This tells me that this "chapter names in a data stream" seems to be a MP4 thing. Isolating it to MP4 should help resolve why this data stream is happening.

You clearly did not get what '-movflags disable_chpl' was about. "chapter names in a data stream" is an Apple thing, mp4 container works fine without it, FFmpeg is just using some default options which try to make the chapters Apple compatible,... (personally I prefer MP4Box)

Cu Selur

Yes, I don't understand "what '-movflags disable_chpl' was about", but, I was trying to figure that out. As you know, I am new to this and trying to learn, honing in on one thing at a time. While I understand "mp4 container works fine without it", trying to achieve chapter names and no data stream in an MP4 is what I am trying to achieve at this time.

At this time, considering all of the advantages and faults with the various containers, I am inclined to move forward with MP4 as the preferred container for my purposes. While I don't have any Apple devices/files, I am not necessarily excluding Apple information in my research. But, I am also trying to document what I am learning so that I have reference material when I come back to various aspects of the research. Selur has been a valuable resource and I appreciate all of the help.