如何使用QMediaPlayer播放流

Question

我已经设置了服务器和视频流,以便我可以使用以下命令行使用ffplay连接到流:

ffplay rtmp://<IP>/path

是否可以使用QMediaPlayer QMediaContent或其他东西连接到此流？

或者也许我可以使用ffserver创建任何其他类型的流.

使用与ffplay相同的路径导致"不支持的url方案!"

通过进一步的实验,我尝试了ffserver http服务器流,但结果是在MFStreamer :: doRead()中Qt崩溃

显然它应该为MFStreamer调用BeginRead,但事实并非如此.

如何使用QMediaPlayer播放视频流？

编辑:这是我的代码

videotest.cpp

#include "videotest.h"
#include <QVBoxLayout>
#include <QVideoWidget>
#include <qmediaplayer.h>
#include <QMediaContent>
#include <QNetworkAccessManager>
#include <QNetworkReply>

struct VideoTest::Private
{
    QMediaPlayer * mediaPlayer;
    QNetworkAccessManager * networkAccessManager;
    QNetworkReply * reply;
};

VideoTest::VideoTest(QWidget *parent)
    : QMainWindow(parent)
{
    d = new Private;
    d->mediaPlayer = new QMediaPlayer(this, QMediaPlayer::StreamPlayback);
    d->networkAccessManager = new QNetworkAccessManager(this);
    ui.setupUi(this);

    QVideoWidget * videoWidget = new QVideoWidget(ui.centralWidget);
    videoWidget->show();
    QPalette palette = videoWidget->palette();
    palette.setColor(QPalette::Background, QColor(0, 0, 0));
    videoWidget->setPalette(palette);

    ui.videoLayout->addWidget(videoWidget);
    d->mediaPlayer->setVideoOutput(videoWidget);

    connect(ui.playButton, SIGNAL(clicked()), d->mediaPlayer, SLOT(play()));
    connect(ui.pauseButton, SIGNAL(clicked()), d->mediaPlayer, SLOT(pause()));
    connect(ui.videoUrlEdit, SIGNAL(editingFinished()), this, SLOT(sourceChanged()));
    connect(d->mediaPlayer, SIGNAL(error()), this, SLOT(stateChanged()));
    connect(d->mediaPlayer, SIGNAL(stateChanged), this, SLOT(stateChanged()));
}

VideoTest::~VideoTest()
{
    delete d;
}

void VideoTest::sourceChanged()
{
    d->reply = d->networkAccessManager->get(QNetworkRequest(ui.videoUrlEdit->text()));
    if(d->reply)
    {
        connect(d->reply, SIGNAL(readyRead()), this, SLOT(networkRequestReady()));
    }
}

void VideoTest::stateChanged()
{
    QString text = ui.textEdit->toPlainText();
    text.append("\n").append(d->mediaPlayer->errorString()).append(" : ").append(d->mediaPlayer->mediaStatus());
    ui.textEdit->setText(text);
}

void VideoTest::networkRequestReady()
{
    d->mediaPlayer->setMedia(QMediaContent(), d->reply);
}

videotest.h

#ifndef VIDEOTEST_H
#define VIDEOTEST_H

#include <QtWidgets/QMainWindow>
#include "ui_videotest.h"

class VideoTest : public QMainWindow
{
    Q_OBJECT

public:
    VideoTest(QWidget *parent = 0);
    ~VideoTest();

public slots:
    void sourceChanged();
    void stateChanged();
    void networkRequestReady();

private:
    Ui::VideoTestClass ui;
    struct Private;
    Private * d;
};

#endif // VIDEOTEST_H

Answer 1

我找到了一种让它发挥作用的方法。

我放弃了Qt。Qt 的人坚持认为它应该可以工作，但无法生成任何有效的配置。他们说如果你从 VLC 流式传输，它应该可以工作，但我没有让它工作。我还尝试了 ffmpeg、ffserver 和 nginx rtmp 流。我让这些东西可以与 mplayer、ffplay、VLC 一起工作，有些甚至可以与 Windows Media Player 一起工作，但从来没有与 QMediaPlayer 一起工作。

我尝试只提供 setMedia 的 URL。我尝试制作一个自定义 QIODevice 来读取流数据并将该数据提供给使用 StreamPlayback 初始化的 QMediaPlayer，但它只是无法成功读取数据。

最后，我需要的只是播放流的东西，是一个 QWidget，并且没有 GPL 许可。

我使用了libVLC和vlc-qt，它们都工作得很好。

遵循这些说明很容易，但您需要记住将头文件从vlc-qt/windows/vlc_headers/2.2/复制到vlc/sdk/include/vlc/plugins（原文如此）。这很重要，如果不这样做，编译过程中可能会出现错误。请注意，如果您的平台的不同版本与我的不匹配，这些路径可能会有所不同。另外，当您阅读本文时，可能没有必要。

视频测试.h

#ifndef VIDEOTEST_H_
#define VIDEOTEST_H_

#include <QtWidgets/QMainWindow>
#include "ui_videotest.h"

class VideoTest: public QMainWindow
{
    Q_OBJECT

    public:
        VideoTest(QWidget * p_parent = 0);
        ~VideoTest();

    public slots:
        void sourceChanged();

    private:
        struct Private;
        Private * d;
        Ui::VideoTestClass ui;
};

#endif

视频测试.cpp

#include "videotest.h"

#include <vlc-qt/Common.h>
#include <vlc-qt/Instance.h>
#include <vlc-qt/Media.h>
#include <vlc-qt/MediaPlayer.h>
#include <vlc-qt/WidgetVideo.h>

struct VideoTest::Private
{
    VlcInstance * vlcInstance;
    VlcMediaPlayer * vlcMediaPlayer;
    VlcMedia * vlcMedia;
    VlcWidgetVideo * vlcVideoWidget;
};

VideoTest::VideoTest(QWidget * p_parent)
{
    d = new Private();
    ui.setupUi(this);

    d->vlcMedia = 0;
    d->vlcInstance = new VlcInstance(VlcCommon::args(), this);
    d->vlcMediaPlayer = new VlcMediaPlayer(d->vlcInstance);
    d->vlcVideoWidget = new VlcWidgetVideo(this);

    d->vlcMediaPlayer->setVideoWidget(d->vlcVideoWidget);
    d->vlcVideoWidget->setMediaPlayer(d->vlcMediaPlayer);

    ui.videoLayout->addWidget(d->vlcVideoWidget);

    connect(ui.playButton, SIGNAL(clicked()), d->vlcMediaPlayer, SLOT(play()));
    connect(ui.pauseButton, SIGNAL(clicked()), d->vlcMediaPlayer, SLOT(pause()));
    connect(ui.videoUrlEdit, SIGNAL(editingFinished()), this, SLOT(sourceChanged()));
}

VideoTest::~VideoTest()
{
    delete d->vlcInstance;
    delete d->vlcMediaPlayer;
    delete d->vlcMedia;

    delete d;
}

VideoTest::sourceChanged()
{
    QUrl url(ui.videoUrlEdit->test());
    if(url.isValid() == false)
    {
        return;
    }

    d->vlcMediaPlayer->stop();

    delete d->vlcMedia;
    d->vlcMedia = new VlcMedia(url.toString(), d->vlcInstance);
    d->vlcMediaPlayer->open(d->vlcMedia);
}

视频测试.ui

自己做吧，我不为你工作：D

只需确保它具有将插入视频小部件的pauseButton、playButton、videoUrlEdit(QLineEdit) 和videoLayout 即可。