platform-notes-wasm.qdoc

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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\page qtmultimedia-wasm.html
\title Qt Multimedia on WebAssembly
\brief Platform notes for WebAssembly
 
This page covers the availability of Qt Multimedia features on WebAssembly.
 
\section1 Limitations
 
\list
\li Due to its asynchronous nature, some features such as getting a list of
QMediaDevices may not be readily available and may take some time to request
permissions and gather the list of devices. With Asyncify/JSPI enabled, device
enumeration happens synchronously. Otherwise use the audioInputsChanged,
audioOutputsChanged, and videoInputsChanged signals to react when devices become
available.
 
\li Camera and Microphone inputs require user permissions, and can only be used
in a secure https context. Firefox may require permission to play video and audio.
 
\li Using and selecting different Codecs/video formats is not currently supported.
These in the browser are more like suggestions or a request, and may not return
the selected codec.
 
\li Playing data from a QIODevice (using \c {setSourceDevice(QIODevice*)}): is partially
supported for video (entire stream (file) is read into memory at once). Not supported
for audio. Streaming from a web URL works. Real-time data input streaming is
not supported.
 
\li Some advanced features such as spatial 3D audio and (Audio/Video)codecs
are not currently supported.
 
\li Files can be served from the/any web server, respective
of \l{https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS}{CORS}.
 
\li Although possible, playing large files stored in the application file system
or in a resource package are discouraged because of the limited size of
the browser's file storage and memory constraints.
 
\li Issues may exist when using the Firefox browser on any platform.
 
\endlist
 
 */