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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\page changes.html
\title Changes in Qt Multimedia
\brief A description of changes in this version of Qt Multimedia
The Qt Multimedia module in Qt 6 replaces the Qt Multimedia module from Qt 5.x.
Existing code that uses Qt Multimedia from Qt 5 can be ported with limited effort. The
\l {changed features} section highlights changes relevant to porting.
\section1 New features in Qt 6.0
There are a number of new features in Qt Multimedia:
\list
\li QMediaCaptureSession class as the central object for media capture
\li Changed QMediaRecorder class to be a high level class for audio/video recording
\li new QMediaRecorder class to handle encoding of data produced in a capture session
\li Setting up the desired encodings when recording has changed significantly, see
QMediaEncoderSettings for details
\li Support for selection of audio, video and subtitle tracks when playing back media files
\li QAudioDecoder is now supported on all platforms
\endlist
\section1 Removed features
\table 70%
\header
\li Removed feature
\li Notes
\row
\li Playlist in QMediaPlayer
\li QMediaPlayer does not do any playlist handling anymore in Qt 6. The QMediaPlayList class
does however still exist and provides this functionality. Users will need to connect the
playlist to the mediaplayer themselves to handle playlists.
\row
\li QAudioProbe and QVideoProbe
\li The audio and video probing API has been removed. A replacement API using custom audio
and video outputs may be added in a future release.
\row
\li QAudioRecorder and the Audio QML type
\li QMediaRecorder and the MediaRecorder QML type provide the same functionality
\row
\li QMediaObject and QMediaBindableInterface
\li These classes have been removed in favor of a more direct API for setting up connections
between objects using e.g. setVideoOutput and QMediaCaptureSession.
\row
\li QCameraViewFinderSettings
\li This class has been removed. Use QCameraFormat to define the resolution and framerate the
camera should be using.
\row
\li QMediaContent
\li The class has been removed. Use QMediaPlayList for play lists and QUrl for individual
media files instead.
\row
\li QSound
\li Use QSoundEffect instead.
\row
\li QVideoFilterRunnable
\li Use shader effects in QML instead or access the QVideoFrame's content in C++.
\row
\li Backend API
\li The backend API of Qt Multimedia is private in Qt 6. Having a public backend API was one
the main things that made supporting and enhancing Qt Multimedia in Qt 5 very difficult.
By making the backend API private, we expect to be able to better support new multimedia
use cases in the future. This includes all classes the contain "Control" or "Abstract"
in the class name in Qt 5.
\row
\li Pluggable backends
\li Qt Multimedia in Qt 6 does not use a plugin infrastructure for its backends anymore.
This means that users do not need to ship those backends with their application anymore
neither. Instead the backend being used is determined at compile time based on the
underlying operating system. Qt uses gstreamer on Linux, WMF on Windows, AVFoundation
on macOS and iOS and the Android multimedia APIs on Android.
\endtable
\section1 Changed features
A number of classes previously offered in Qt Multimedia or Qt Multimedia Kit have
changed in ways that may affect previously written code. This table highlights such changes.
\table 70%
\header
\li Changed feature
\li Notes
\row
\li Handling of Camera resolutions and frame rates
\li Handling of those has been simplified and a new QCameraFormat class helps selecting
the correct resolution and frame rate on the camera.
\row
\li Video output handling on the C++ side has changed significantly.
\li QAbstractVideoSurface has been replaced by the QVideoSink class, and generic rendering
support has been enhanced to cover all pixel formats supported by Qt Multimedia
\row
\li Metadata types
\li QMediaMetaData has changed significantly, mainly moving from string based
to enum based keys, and reducing the set of supported keys to the ones that
can be supported on most platforms.
\row
\li QMediaFormat and QMediaEncoderSettings
\li Handling of formats for encoded media and the settings for the media encoder have
changed significantly. While Qt 5 provided a string based API and separated file format,
audio and video codecs into 3 classes, Qt 6 does unify the formats in the QMediaFormat class,
and encoder settings in QMediaEncoderSettings. Setting up of file formats and codecs is now
enum based and doesn't use strings anymore. This puts some limitations on the set of codecs
that can be used, but helps provide a consistent cross-platform API and reduces the changes
for inconsistencies.
\endtable
*/
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