MP4 muxers

[RBO]

set a global title field

Usually people use -tags title="..."

omit tagged date

If you set a tag to null then it is removed, see https://wiki.gpac.io/MP4Box/mp4box-other-opts/.

Does MP4Box (as part of GPAC) depend on ffmpeg?

It does (optionally) since GPAC 1.0 in 2020. We rewrote the core of GPAC to reuse the same framework ("filters") that you see in the new 'gpac' app. Add -graph to your command-line to see the MP4Box processing graph.

Now MP4Box can leverage other libraries. FFmpeg is a kind of last-resort fallback.

To come back to your case, I would expect to see:

dtsc [ODE]:                   DTS Coherent Acoustics and Digital Surround Audio (audio/dts)
dtsh [O]:                     DTS-HD High Resolution Audio and DTS-Master Audio (audio/dts)
dtsl [O]:                     DTS-HD Substream containing only XLLAudio (audio/dts)
dtse [O]:                     DTS Express low bit rate Audio (audio/dts)
dtsx [O]:                     DTS-X UHD Audio Profile 2 (audio/dts)
dtsy [O]:                     DTS-X UHD Audio Profile 3 (audio/dts)

This is on Windows, correct?

[LigH]

Yes, Windows. Building from sources in an MSYS2/MinGW environment with GCC 14.2.

Does it require to configure with a special parameter to include ffmpeg support?

[RBO]

No. It really seems GPAC doesn't see the DTS codec in FFmpeg. I propose to reproduce your media-autobuild_suite build, let me know if you use specific options.

[LigH]

This archive contains a few relevant files, mainly media-autobuild_suite.ini (configured for many codecs with additional separate executables besides ffmpeg which gets built as static EXE with a custom set of libraries) and ffmpeg_options.txt; may be way too much for your needs, you can probably safely disable many codecs to run your test, the dca codec is part of libavcodec (the ffmpeg core) anyway, does not depend on additional libraries.

I would recommend to configure M-AB-S from scratch, select only static build, GPL, minimal set for ffmpeg; disable most codecs except GPAC/MP4Box, and enable building of separate codecs besides ffmpeg.

The resulting binaries are not installed in the Windows\System and not in the MSYS2 base environment but in local directories.

[GeoffreyA]

Originally Posted by RBO

Usually people use -tags title="..."

Thanks. It worked.

[RBO]

M-AB-S builds GPAC before FFmpeg. So obviously GPAC can't rely on FFmpeg in these builds.

Second remark: M-AB-S seems to rely on libgpac_static only (code). Does this script aims at building static binaries whenever possible?

FYI the build failed for me because ccache said there are too many files in the FFmpeg build. Retrying the build from a root folder. It takes a lot of time because I have continuous network issues and the system continuous updates dozens of git repos when relaunched.

[LigH]

Originally Posted by RBO

M-AB-S builds GPAC before FFmpeg. So obviously GPAC can't rely on FFmpeg in these builds.

Good to know, will tell the maintainers about it, so they can possibly rearrange.

Originally Posted by RBO

Second remark: M-AB-S seems to rely on libgpac_static only (code). Does this script aims at building static binaries whenever possible?

Not always. You can try to build ffmpeg with shared DLLs as well. Some other separate tools may prefer static building "always" if there used to be linking issues when trying to run a dynamic-link build in the past. Needs to be answered by the maintainers.

Originally Posted by RBO

FYI the build failed for me because ccache said there are too many files in the FFmpeg build. Retrying the build from a root folder. It takes a lot of time because I have continuous network issues and the system continuous updates dozens of git repos when relaunched.

Very useful information. I know there is an issue with a "too long command line" when building ffmpeg with dynamic linking and a lot of enabled optional modules (that was the reason why I recommended to you to configure from scratch with a minimal ffmpeg with GPL license), and knowing that ccache may be the bottleneck here should help greatly solving it.

PS: See M-AB-S issue 2801.

[filler56789]

F.W.I.W., I downloaded the latest GPAC-installer available at videohelp dot com,
and saw that it uses the (lib)av libraries...
BUT it cannot do everything that the (lib)av DLLs are capable of doing...
which raises the question:
¿what is the point, then?

In comparison, the L-Smash muxer.exe rev1477 18a9ed2 filesize is only 569 kB.
And obviously, it does not depend on the FFmpeg stuff.

Bottom line is, something very-wrong cannot be right.

[RBO]

BUT it cannot do everything that the (lib)av DLLs are capable of doing...

Ah. What can't it do?

the L-Smash muxer.exe rev1477 18a9ed2 filesize is only 569 kB

MP4Box built with with "--isomedia-only --static-bin --strip" is the closest comparable I think. It weighs around 1MB and handles network, multithreading, configurable cache, etc. Do you need something smaller? What's your need?