[Phone] Please enable opus audio codec support in qtmultimedia

I'm attaching a debdiff against qtmultimedia-opensource-src_5.4.1-1ubuntu19~overlay4 vivid package which contains the cleaned qtmultimedia patch. Tested on mako (rc-channel).

This is the qtmultimedia-opensource-src patch extracted from previous debdiff, this patch should be applied also to xenial/yakkety packages

This is a debdiff for gst-plugins-bad0.10_0.10.23-7.4ubuntu2 vivid package. opus plugin is now installed by a new gstreamer0.10-opus package. Tested on mako, not needed in xenial/yakkety since the opus plugin is in -base package.

I tested these packages using ~d.filoni/telegram-app/audio_receiving_and_sending telegram-app branch (stable enough), it doesn't work without opusdec support. The recorder settings are declared in the following code (telegram/app/qml/components/AudioRecordingBar.qml):

    AudioEncoderSettings {
        id: audioEncoderSettings
        codec: "audio/x-opus"
        sampleRate: 16000
        channelCount: 1
    }

The AudioEncoderSettings component is provided by AsemanAudioEncoderSettings C++ class (parent class: QAudioEncoderSettings). The recorder component is provided by AsemanAudioRecorder class which internally uses QAudioRecorder. Aseman class files can be found in telegram/app/asemantools/ directory.

Hi Devid,
"it doesn't work without opusdec support" -> I'm a bit confused by this sentence, do you mean that it doesn't work without your patch (but with the attached patch it starts working), or that the problem does not have a solution yet?

Hi Andrea,
my telegram-app branch adds voice messages sending feature however it doesn't work without opusenc (opusdec is a typo) support.
Opusenc support is introduced by the qtmultimedia patch I attached, so this bug has a solution :) Everything is working fine on my device (mako) with my patches and I'm able to send telegram voice messages.

To be clear these patches are waiting for a review ;)

Sorry Devid for the wait, we are definitely very happy to land these fixes! We need to just decide who/when will land it.

So action items, since I'm away at least next week:
1. Jin will check with Lukasz (sil2100) on whether he could help getting a silo to land the fixes to vivid OTA. The patches from Devid should be pretty much fine as is.
2. Someone please re-check if this is already fixed in xenial-overlay and zesty or not. This week I heard it would be fixed in the very latest packages, but need to confirm.

Oh, don't worry for the wait, I know you're busy working on higher-priority tasks ;) I'm really happy everything is fine, I'll continue to work on the telegram patch once I have free time :)

If this is going to be fixed in other ways in xenial/yakkety/zesty, please make sure that the QAudioEncoderSettings codec string is "audio/x-opus" (I used the one in gstreamer opusenc plugin documentation but I'm not really sure about it)

Will get to landing the QtMultimedia patch sometime soon.

@timo-jyrinki regarding whether this is fixed in xenial or newer:

1. xenial uses qtmultimedia 5.5.1, which depends on gstreamer1.0
2. gstreamer1.0 moved the opus[dec|enc] codecs to plugins-base in version 1.8, which is included by default in phone images

So yes, this should be solved in xenial and newer.

Note also that this issue is happening because qtmultimedia 5.4.1 uses old gstreamer 0.10. In fact you can already use opus in OTA13 by using directly gstreamer1.0 instead of via Qt.

I can confirm the gstreamer patch is not needed in xenial as described by Alfonso, however qtmultimedia patch is needed as the opus encoder is installed but it is not recognized by QGstreamerAudioEncode (it is not mapped).

Another note: playing opus works just fine because the code path in that case goes through qtmultimedia -> qtubuntu-media -> media-hub -> gstreamer 1.0.

So the missing thing is opus encoding in vivid for qtmultimedia/gstreamer 0.10, and that is what Devid's patches fix.

@d.filoni oh, I see, there is some glue code missing in qtmultimedia in all versions. That needs landing in xenial too indeed :)

@d.filoni, you can find gstreamer0.10 and qtmultimedia packages in https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/2147

Please give the silo a try and let us know if things work as expected.

@Alfonso: thank you, I'll test it once I'm back at home. Please note: in my qtmultimedia patch I haven't added gstreamer0.10-opus package as depencency so it needs to be installed on devices (I don't know how packages selection works in phone).

Tested on mako (vivid). Silo #2147 works fine (after installing gstreamer0.10-opus package) ;)

This bug was fixed in the package qtmultimedia-opensource-src - 5.6.1-2ubuntu3~1

---------------
qtmultimedia-opensource-src (5.6.1-2ubuntu3~1) zesty; urgency=medium

  [ Devid Antonio Filoni ]
  * Add opusenc support needed by Telegram app (LP: #1630399)

 -- Alfonso Sanchez-Beato (email Canonical) <email address hidden> Fri, 04 Nov 2016 12:42:19 +0100

Also fixed in vivid's gst0.10, and added gstreamer0.10-opus to vivid seed.