Solution: cannot export to M4A / AAC because Gstream has changed their plugin API

[Wang Xuancong]

When saving recorded audio in M4A / AAC format, it gives the following error:
gst_object_unref: assertion 'object != NULL' failed
Error:To support m4a format you should install Gstreamer-plugins for .
Error:Installation of Gstreamer-plugins failed (GST_INSTALL_PLUGINS_HELPER_MISSING).

I have checked that I have installed Gstreamer-plugins, and running Gstream command line can convert any audio into .m4a format:
gst-launch-1.0 filesrc location=/tmp/test.mp3 ! mpegaudioparse ! mpg123audiodec ! audioconvert ! avenc_aac ! mp4mux ! filesink location=/home/xuancong/Desktop/test.m4a

Solution:
In media-profiles.c, the default profile for M4A is out-of-date as Gstreamer has changed their plugin API, changing the following line will solve the problem:

Existing wrong:
{"CD Quality, AAC 44KHz", "m4a", "", "audio/x-raw,rate=44100,channels=2 ! avenc_aac compliance=-2 ! avmux_mp4"}

New correct:
{"CD Quality, AAC 44KHz", "m4a", "", "audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux"}

Thanks!
Xuancong

[moma (osmoma)]

Hello Wang,

Many thanks for your finding.
I will fix the media-profiles.c file ASAP.

Notice:
I have not worked on audio-recorder for a long time now.
The entire code should be re-written, but that is a major task.

Thanks again Wang.
Well done.

 Cumprimentos
  Osmo Antero
   Portugal

[moma (osmoma)]

Hello Xuancong,

The new version is audio-recorder 3.2.2.

Changes:
https://bazaar.launchpad.net/~audio-recorder/audio-recorder/trunk/revision/1935

I have only re-compiled packages for Ubuntu 20.10 (Groovy, Ubuntu`s development version).
Launchpad is now compiling the packages for audio-recorder - 3.2.2~groovy.
https://launchpad.net/~audio-recorder/+archive/ubuntu/ppa/+packages

But I might be able to copy the packages over to Ubuntu 20.04.
Launchpad.net has a copy package function.
I will try it now.

Cumprimentos
  Osmo Antero
   Portugal

[moma (osmoma)]

Re-hello,

I have some problems recording (to .m4a) from the audio-recorder GUI, even the command line in a terminal window works fine.

$ gst-launch-1.0 -e pulsesrc ! queue ! audioresample ! audioconvert ! audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink location=test.m4a

I have to test it better later on.

Please test the new version 3.2.2 and tell your findings. Is it ok?

Cumprimentos
  Osmo Antero
   Portugal

[moma (osmoma)]

Hello again,
I can now see why the m4a pipeline records well on the command line, but
fails in the GUI (when run by audio-recorder).

This pipeline is ok.
gst-launch-1.0 -e pulsesrc ! queue ! audioresample ! audioconvert !
audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink
location=test.m4a

This fails.
gst-launch-1.0 pulsesrc ! queue ! audioresample ! audioconvert !
audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink
location=test.m4a

The difference is the -e (--eos-on-shutdown) option.
See:
$ gst-launch-1.0 --help
...
-e, --eos-on-shutdown Force EOS on sources before shutting the pipeline
down
...
----------
The GUI does not issue the --eos-on-shutdown option, therefore the test.m4a
file is not valid.
I think the -e option caused some problems or freezing earlier and was
removed.
Let us see if it is/was in the code.

$ cd trunk
$ grep "eos" src/*.c

src/gst-pipeline.c: // Add -e (--eos-on-shutdow) option.
src/gst-recorder.c: // gst_element_send_event(g_pipeline,
gst_event_new_eos());
src/gst-recorder.c:static void rec_eos_msg_cb(GstBus *bus, GstMessage *msg,
void *userdata) {
src/gst-recorder.c: g_signal_connect(bus, "message::eos",
G_CALLBACK(rec_eos_msg_cb), NULL);

Most pipelines work fine without the -e (EOS) message.
Obviously mp4mux is not happy without it.

I will see into this issue later on.

Cumprimentos
  Osmo Antero
   Portugal

moma <email address hidden> escreveu no dia domingo, 24/01/2021 à(s)
11:51:

> Re-hello,
>
> I have some problems recording (to .m4a) from the audio-recorder GUI,
> even the command line in a terminal window works fine.
>
>
> $ gst-launch-1.0 -e pulsesrc ! queue ! audioresample ! audioconvert !
> audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink
> location=test.m4a
>
> I have to test it better later on.
>
> Please test the new version 3.2.2 and tell your findings. Is it ok?
>
> Cumprimentos
> Osmo Antero
> Portugal
>
> --
> You received this bug notification because you are subscribed to Audio
> Recorder.
> https://bugs.launchpad.net/bugs/1912876
>
> Title:
> Solution: cannot export to M4A / AAC because Gstream has changed their
> plugin API
>
> Status in Audio Recorder:
> New
>
> Bug description:
> When saving recorded audio in M4A / AAC format, it gives the following
> error:
> gst_object_unref: assertion 'object != NULL' failed
> Error:To support m4a format you should install Gstreamer-plugins for .
> Error:Installation of Gstreamer-plugins failed
> (GST_INSTALL_PLUGINS_HELPER_MISSING).
>
>
> I have checked that I have installed Gstreamer-plugins, and running
> Gstream command line can convert any audio into .m4a format:
> gst-launch-1.0 filesrc location=/tmp/test.mp3 ! mpegaudioparse !
> mpg123audiodec ! audioconvert ! avenc_aac ! mp4mux ! filesink
> location=/home/xuancong/Desktop/test.m4a
>
>
> Solution:
> In media-profiles.c, the default profile for M4A is out-of-date as
> Gstreamer has changed their plugin API, changing the following line will
> solve the problem:
>
> Existing wrong:
> {"CD Quality, AAC 44KHz", "m4a", "", "audio/x-raw,rate=44100,channels=2
> ! avenc_aac compliance=-2 ! avmux_mp4"}
...

[Wang Xuancong (xuancong84)]

Thanks Osmo Antero.
From your code, I can see that working on C/C++ is quite inefficient,
future GUI should also use Python which is much easier.

Cheers,
xuancong

On Sun, Jan 24, 2021 at 7:20 PM moma <email address hidden> wrote:

> Hello Xuancong,
>
> The new version is audio-recorder 3.2.2.
>
> Changes:
>
> https://bazaar.launchpad.net/~audio-recorder/audio-recorder/trunk/revision/1935
>
> I have only re-compiled packages for Ubuntu 20.10 (Groovy, Ubuntu`s
> development version).
> Launchpad is now compiling the packages for audio-recorder - 3.2.2~groovy.
> https://launchpad.net/~audio-recorder/+archive/ubuntu/ppa/+packages
>
>
> But I might be able to copy the packages over to Ubuntu 20.04.
> Launchpad.net has a copy package function.
> I will try it now.
>
> Cumprimentos
> Osmo Antero
> Portugal
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1912876
>
> Title:
> Solution: cannot export to M4A / AAC because Gstream has changed their
> plugin API
>
> Status in Audio Recorder:
> New
>
> Bug description:
> When saving recorded audio in M4A / AAC format, it gives the following
> error:
> gst_object_unref: assertion 'object != NULL' failed
> Error:To support m4a format you should install Gstreamer-plugins for .
> Error:Installation of Gstreamer-plugins failed
> (GST_INSTALL_PLUGINS_HELPER_MISSING).
>
>
> I have checked that I have installed Gstreamer-plugins, and running
> Gstream command line can convert any audio into .m4a format:
> gst-launch-1.0 filesrc location=/tmp/test.mp3 ! mpegaudioparse !
> mpg123audiodec ! audioconvert ! avenc_aac ! mp4mux ! filesink
> location=/home/xuancong/Desktop/test.m4a
>
>
> Solution:
> In media-profiles.c, the default profile for M4A is out-of-date as
> Gstreamer has changed their plugin API, changing the following line will
> solve the problem:
>
> Existing wrong:
> {"CD Quality, AAC 44KHz", "m4a", "", "audio/x-raw,rate=44100,channels=2
> ! avenc_aac compliance=-2 ! avmux_mp4"}
>
> New correct:
> {"CD Quality, AAC 44KHz", "m4a", "", "audio/x-raw,rate=44100,channels=2
> ! avenc_aac ! mp4mux"}
>
> Thanks!
> Xuancong
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/audio-recorder/+bug/1912876/+subscriptions
>

[moma (osmoma)]

Hi,
Yes, the gst_element_send_event(...) was earlier commented out in
the rec_stop_recording(...) function.

I have to find a better solution.

Osmo Antero

Osmo Antero <email address hidden> escreveu no dia domingo, 24/01/2021 à(s)
13:44:

> Hello again,
> I can now see why the m4a pipeline records well on the command line, but
> fails in the GUI (when run by audio-recorder).
>
> This pipeline is ok.
> gst-launch-1.0 -e pulsesrc ! queue ! audioresample ! audioconvert !
> audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink
> location=test.m4a
>
> This fails.
> gst-launch-1.0 pulsesrc ! queue ! audioresample ! audioconvert !
> audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink
> location=test.m4a
>
> The difference is the -e (--eos-on-shutdown) option.
> See:
> $ gst-launch-1.0 --help
> ...
> -e, --eos-on-shutdown Force EOS on sources before shutting the pipeline
> down
> ...
> ----------
> The GUI does not issue the --eos-on-shutdown option, therefore the
> test.m4a file is not valid.
> I think the -e option caused some problems or freezing earlier and was
> removed.
> Let us see if it is/was in the code.
>
> $ cd trunk
> $ grep "eos" src/*.c
>
> src/gst-pipeline.c: // Add -e (--eos-on-shutdow) option.
> src/gst-recorder.c: // gst_element_send_event(g_pipeline,
> gst_event_new_eos());
> src/gst-recorder.c:static void rec_eos_msg_cb(GstBus *bus, GstMessage
> *msg, void *userdata) {
> src/gst-recorder.c: g_signal_connect(bus, "message::eos",
> G_CALLBACK(rec_eos_msg_cb), NULL);
>
> Most pipelines work fine without the -e (EOS) message.
> Obviously mp4mux is not happy without it.
>
> I will see into this issue later on.
>
> Cumprimentos
> Osmo Antero
> Portugal
>
> moma <email address hidden> escreveu no dia domingo, 24/01/2021
> à(s) 11:51:
>
>> Re-hello,
>>
>> I have some problems recording (to .m4a) from the audio-recorder GUI,
>> even the command line in a terminal window works fine.
>>
>>
>> $ gst-launch-1.0 -e pulsesrc ! queue ! audioresample ! audioconvert !
>> audio/x-raw,rate=44100,channels=2 ! avenc_aac ! mp4mux ! filesink
>> location=test.m4a
>>
>> I have to test it better later on.
>>
>> Please test the new version 3.2.2 and tell your findings. Is it ok?
>>
>> Cumprimentos
>> Osmo Antero
>> Portugal
>>
>> --
>> You received this bug notification because you are subscribed to Audio
>> Recorder.
>> https://bugs.launchpad.net/bugs/1912876
>>
>> Title:
>> Solution: cannot export to M4A / AAC because Gstream has changed their
>> plugin API
>>
>> Status in Audio Recorder:
>> New
>>
>> Bug description:
>> When saving recorded audio in M4A / AAC format, it gives the following
>> error:
>> gst_object_unref: assertion 'object != NULL' failed
>> Error:To support m4a format you should install Gstreamer-plugins for .
>> Error:Installation of Gstreamer-plugins failed
>> (GST_INSTALL_PLUGINS_HELPER_MISSING).
>>
>>
>> I have checked that I have installed Gstreamer-plugins, and running
>> Gstream command line can convert any audio into .m4a format:
>> gst-launch-1.0 filesrc location=/tmp/test.mp3 ! mpegaudioparse !
>> mpg123audiodec ! audioconvert ! avenc_aac ! mp4mux ! filesi...

[moma (osmoma)]

Re-hi,

The latest version 3.2.3 should now record .m4a audio well.

Please see:
https://launchpad.net/~audio-recorder/+archive/ubuntu/ppa
audio-recorder 3.2.3~hirsute
audio-recorder 3.2.3~groovy

Obrigado
  Osmo Antero

[Marcel Seydel (marcelspunkt-deactivatedaccount)]

Hello,

i'm using the new Version. Installed on Arch Linux 5.10.15 over the AUR
https://aur.archlinux.org/packages/audio-recorder/

If I try to record aac-m4a files, it wont work and i get such error messages:

(audio-recorder:5231): GStreamer-CRITICAL **: 13:06:16.703: gst_object_unref: assertion 'object != NULL' failed
Error:To support m4a format you should install Gstreamer-plugins for avenc_aac, avmux_mp4.
Error:Installation of Gstreamer-plugins failed (GST_INSTALL_PLUGINS_HELPER_MISSING).
Error:Error:Missing Gstreamer element: avenc_aac.
Installation string for avenc_aac: gstreamer|1.0|audio-recorder|GStreamer-Element avenc_aac|element-avenc_aac.
Error:Missing Gstreamer element: avmux_mp4.
Installation string for avmux_mp4: gstreamer|1.0|audio-recorder|GStreamer-Element avmux_mp4|element-avmux_mp4.

gst-plugins-bad from official repositories is installed:
https://archlinux.org/packages/extra/x86_64/gst-plugins-bad/