我无法帮助您解决主要问题,但我可以给您一个videoSurface
的使用示例。您可以像这样使用“可写videoSurface
”:
我的示例由三个主要步骤组成:
- 编写一个具有QAbstactVideoSurface属性的类。此类将是您的视频提供者,可以通过调用其present()函数在VideoOutput上显示帧。
videoadapter.h
#ifndef VIDEOADAPTER_H
#define VIDEOADAPTER_H
#include <QObject>
#include <QAbstractVideoSurface>
#include <QVideoSurfaceFormat>
#include <QTimer>
class VideoAdapter : public QObject
{
Q_OBJECT
Q_PROPERTY(QAbstractVideoSurface* videoSurface READ videoSurface WRITE setVideoSurface NOTIFY signalVideoSurfaceChanged)
public:
explicit VideoAdapter(QObject *parent = nullptr);
QAbstractVideoSurface *videoSurface() const;
void setVideoSurface(QAbstractVideoSurface *videoSurface);
signals:
void signalVideoSurfaceChanged();
private slots:
void slotTick();
private:
void startSurface();
private:
QAbstractVideoSurface *mVideoSurface;
QVideoSurfaceFormat *mSurfaceFormat;
QImage *mImage;
QTimer mTimer;
};
#endif
videoadapter.cpp
#include "videoadapter.h"
#include <QDebug>
VideoAdapter::VideoAdapter(QObject *parent)
: QObject(parent), mVideoSurface(nullptr), mSurfaceFormat(nullptr)
{
mTimer.setInterval(1000);
connect(&mTimer, &QTimer::timeout, this, &VideoAdapter::slotTick);
}
QAbstractVideoSurface *VideoAdapter::videoSurface() const
{
return mVideoSurface;
}
void VideoAdapter::setVideoSurface(QAbstractVideoSurface *videoSurface)
{
if(videoSurface != mVideoSurface)
{
mVideoSurface = videoSurface;
emit signalVideoSurfaceChanged();
startSurface();
mTimer.start();
}
}
void VideoAdapter::slotTick()
{
QVideoFrame frame(*mImage);
mVideoSurface->present(frame);
}
void VideoAdapter::startSurface()
{
mImage = new QImage("../resources/images/test.jpg");
auto pixelFormat = QVideoFrame::pixelFormatFromImageFormat(mImage->format());
mSurfaceFormat = new QVideoSurfaceFormat(mImage->size(), pixelFormat);
if(!mVideoSurface->start(*mSurfaceFormat))
{
qDebug() << "Surface couldn't be started!";
}
}
这个类只加载一个图像文件并使用计时器显示它,但在您的情况下,您将拥有一个帧源,因此您可以更改它以适应您的需求。如果您可以将您的帧转换为QImage
或QVideoFrame
,您可以像这样显示它。
You have to make this class usable in QML. In my case i created an object and made it visible to QML via setting it as a property.
int main(int argc, char *argv[])
{
QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
QGuiApplication app(argc, argv);
QQmlApplicationEngine engine;
QQmlDebuggingEnabler enabler;
VideoAdapter adapter;
engine.rootContext()->setContextProperty("videoAdapter", &adapter);
const QUrl url(QStringLiteral("qrc:/main.qml"));
QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
&app, [url](QObject *obj, const QUrl &objUrl) {
if (!obj && url == objUrl)
QCoreApplication::exit(-1);
}, Qt::QueuedConnection);
engine.load(url);
return app.exec();
}
You give this object to the VideoOutput as source in QML.
Window {
visible: true
width: 640
height: 480
color: "black"
title: qsTr("Video Player")
VideoOutput {
id: videoPlayer
anchors.fill: parent
source: videoAdapter
}
}
正如我所说的,这个例子很简单,只加载一个图片并周期性地显示那张图片。
这个问题是一个老问题了,你可能已经不再关注它,但希望它至少能帮助其他人。