[Development] New Qt Multimedia

[Lars Knoll]

On 27 May 2021, at 15:25, Rodrigo Gonçalves de Oliveira <rodrigo.golive at gmail.com> wrote:


Also, this is how I define and change different audio devices ("gst-pipeline: ... audio_sink=\"alsasink device=%1\") on demand.
Are there plans to have an easy way to change the output audio device? Think on an embedded system, within a media app and multiple audio devices, where the user want to change the audio output device at any time.

Have a look at QMediaDevices that lets you discover different inputs/outputs. You can also get notifications when a new output becomes available (eg. because you connected a headset).

QMediaPlayer and QMediaCaptureSession have an API that let you choose the output you want based on the available devices you can get from QMediaDevices.

Cheers,
Lars

On Thu, May 27, 2021 at 9:54 AM Samuel Gaist via Development <development at qt-project.org<mailto:development at qt-project.org>> wrote:

> On 27 May 2021, at 14:35, Lars Knoll <lars.knoll at qt.io<mailto:lars.knoll at qt.io>> wrote:
>
>> On 27 May 2021, at 14:25, Eike Hein <hein at kde.org<mailto:hein at kde.org>> wrote:
>>
>> May 27, 2021 8:14 AM, "Lars Knoll" <lars.knoll at qt.io<mailto:lars.knoll at qt.io>> wrote:
>>> The one thing I want to avoid is what we had in Qt 5, where you could force Qt MM to use a
>>> different/custom gstreamer pipeline based on environment variables. That part made maintaining the
>>> code base extremely hard. Other than that I’m of course open for patches and improvements. If some
>>> integration points are needed, we can discuss those separately, but unless they are trivial, they
>>> will probably need to wait until after 6.2.
>>
>> Hmm - does that mean the `gst-pipeline:` URL scheme for `setMedia`/the `source`
>> prop is getting dropped as well?
>
> That’s correct. It’s has honestly been a huge cludge, and something we didn’t have anywhere else. I’d rather see that we fix issues inside Qt MM instead of working around them with hacks such as this one.
>>
>> If memory serves right, this was possible accidentally at some point and then
>> was raised to the status of Official Footgun in 5.12+:
>>
>> https://doc.qt.io/qt-5/qmediaplayer.html#setMedia
>
> Footgun is probably the right name for it, and a reason I don’t want to continue with it for Qt 6.
>>
>> A potential troublemaker for sure, but also very powerful. With QtGStreamer
>> being deprecated (an old set of Qt bindings to GStreamer API - also something
>> at least one KDE app I'm aware of still carries an internal fork of, sadly),
>> a QtMM w/ custom pipeline support sort of the next best thing.
>
> Lets rather have a look at the use cases that people want to have supported and how we can get those working.
>
> Cheers,
> Lars
>
> _______________________________________________
> Development mailing list
> Development at qt-project.org<mailto:Development at qt-project.org>
> https://lists.qt-project.org/listinfo/development

I think one of the main use case I have seen for custom GStreamer pipelines is to be able to get rtsp or other network streams in Qt applications.

Best regards

Samuel

_______________________________________________
Development mailing list
Development at qt-project.org<mailto:Development at qt-project.org>
https://lists.qt-project.org/listinfo/development


--
Rodrigo Oliveira
Florianópolis, Brazil
rodrigo.golive at gmail.com<mailto:rodrigo.golive at gmail.com>
+55 48 91605760
http://br.linkedin.com/in/rodrigogoliveira
_______________________________________________
Development mailing list
Development at qt-project.org
https://lists.qt-project.org/listinfo/development
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.qt-project.org/pipermail/development/attachments/20210527/160f712b/attachment-0001.html>