一、环境介绍

操作系统: win10 64位

QT版本: QT5.12.6

编译器: MinGW 32

二、mdk-sdk 介绍

github 首页地址: https://github.com/wang-bin/mdk-sdk

Features

Simple and powerful API set
Cross platform: Windows, UWP, Linux, macOS, Android, iOS, Raspberry Pi
Hardware accelerated decoding and 0-copy GPU rendering for all platforms
OpenGL, D3D11, Vulkan and Metal rendering w/ or w/o user provided context
Integrated with any gui toolkits or apps via OpenGL, D3D11, Vulkan and Metal (OBS, Qt, SDL, glfw, SFML etc.) easily
Seamless/Gapless media and bitrate switch for any media
HDR rendering in GPU
Optimized Continuous seeking. As fast as mpv, but much lower cpu, memory and gpu load. Suitable for timeline preview
Smart FFmpeg runtime. See https://github.com/wang-bin/mdk-sdk/wiki/FFmpeg-Runtime

mdk-sdk的API使用介绍: https://github.com/wang-bin/mdk-sdk/wiki/Player-APIs

mdk-sdk的使用例子(CSDN): https://download.csdn.net/download/xiaolong1126626497/16273881

mdk-sdk的SDK包(CSDN)--截止当前是最新版本: https://download.csdn.net/download/xiaolong1126626497/16273875

mdk-sdk的使用例子(GitHub):https://github.com/wang-bin/mdk-examples

三、工程源码

3.1 运行效果

这个Demo只是简单的测试播放器，很多功能没去写，简单测试下性能；所以界面没有怎么去弄。

3.2 pro工程文件

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets opengl

CONFIG += c++17 utf8_source

MDK_SDK = $$PWD/mdk-sdk
INCLUDEPATH += $$MDK_SDK/include

MDK_ARCH = x86

LIBS += -L$$MDK_SDK/lib/$$MDK_ARCH -lmdk
LIBS += -L$$MDK_SDK/bin/$$MDK_ARCH

# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
    QMDKWidget.cpp \
    main.cpp \
    widget.cpp

HEADERS += \
    QMDKWidget.h \
    widget.h

FORMS += \
    widget.ui

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

3.3 QMDKWidget.cpp

/*
 * Copyright (c) 2020 WangBin <wbsecg1 at gmail.com>
 * MDK SDK with QOpenGLWidget example
 */
#include "QMDKWidget.h"
#include "mdk/Player.h"
#include <QCoreApplication>
#include <QDebug>
#include <QDir>
#include <QKeyEvent>
#include <QOpenGLContext>
#include <QStringList>
#include <QScreen>

using namespace MDK_NS;
QMDKWidget::QMDKWidget(QWidget *parent, Qt::WindowFlags f)
    : QOpenGLWidget(parent, f)
    , player_(std::make_shared<Player>())
{
    player_->setVideoDecoders({"VT", "VAAPI", "MFT:d3d=11", "DXVA", "MMAL", "AMediaCodec:java=1:copy=0:surface=1:async=0", "FFmpeg"});

    player_->setRenderCallback([this](void*){
        QMetaObject::invokeMethod(this, "update", Qt::QueuedConnection);
    });


}

QMDKWidget::~QMDKWidget()
{
    makeCurrent();
    player_->setVideoSurfaceSize(-1, -1); // cleanup gl renderer resources
}

void QMDKWidget::setDecoders(const QStringList &dec)
{
    std::vector<std::string> v;
    foreach (QString d, dec) {
        v.push_back(d.toStdString());
    }
    player_->setVideoDecoders(v);
}

void QMDKWidget::setMedia(const QString &url)
{
    player_->setMedia(url.toUtf8().constData());
}

void QMDKWidget::play()
{
    player_->setState(State::Playing);
}

void QMDKWidget::pause()
{
    player_->setState(State::Paused);
}

void QMDKWidget::stop()
{
    player_->setState(State::Stopped);
}

bool QMDKWidget::isPaused() const
{
    return player_->state() == State::Paused;
}

void QMDKWidget::seek(qint64 ms)
{
    player_->seek(ms);
}

qint64 QMDKWidget::position() const
{
    return player_->position();
}

void QMDKWidget::snapshot() {
    Player::SnapshotRequest sr{};
    player_->snapshot(&sr, [](Player::SnapshotRequest *_sr, double frameTime) {
        const QString path = QDir::toNativeSeparators(
            QString("%1/%2.png")
                .arg(QCoreApplication::applicationDirPath())
                .arg(frameTime));
        return path.toStdString();
        // Here's how to convert SnapshotRequest to QImage and save it to disk.
        /*if (_sr) {
            const QImage img = QImage(_sr->data, _sr->width, _sr->height,
                                      QImage::Format_RGBA8888);
            if (img.save(path)) {
                qDebug() << "Snapshot saved:" << path;
            } else {
                qDebug() << "Failed to save:" << path;
            }
        } else {
            qDebug() << "Snapshot failed.";
        }
        return "";*/
    });
}

void QMDKWidget::resizeGL(int w, int h)
{
    //auto s = screen();
    //qDebug("resizeGL>>>>>dpr: %f, logical dpi: (%f,%f), phy dpi: (%f,%f)", s->devicePixelRatio(), s->logicalDotsPerInchX(), s->logicalDotsPerInchY(), s->physicalDotsPerInchX(), s->physicalDotsPerInchY());
    player_->setVideoSurfaceSize(w*devicePixelRatio(), h*devicePixelRatio());
}

void QMDKWidget::paintGL()
{
    player_->renderVideo();
}

void QMDKWidget::keyPressEvent(QKeyEvent *e)
{
    switch (e->key()) {
    case Qt::Key_Space: {
        if (isPaused())
            play();
        else
            pause();
    }
        break;
    case Qt::Key_Right:
        seek(position() + 10000);
        break;
    case Qt::Key_Left:
        seek(position() - 10000);
        break;
    case Qt::Key_Q:
        qApp->quit();
        break;
    case Qt::Key_C:
        //if (QKeySequence(e->modifiers() | e->key()) == QKeySequence::Copy) {
            snapshot();
        //}
        break;
    default:
        break;
    }
}

3.4 QMDKWidget.h

/*
 * Copyright (c) 2020 WangBin <wbsecg1 at gmail.com>
 * MDK SDK with QOpenGLWindow example
 */
#pragma once
#include <QOpenGLWidget>
#include <memory>

namespace mdk {
class Player;
}
class QMDKWidget : public QOpenGLWidget
{
public:
    QMDKWidget(QWidget *parent = nullptr, Qt::WindowFlags f = Qt::WindowFlags());
    ~QMDKWidget();
    void setDecoders(const QStringList& dec);
    void setMedia(const QString& url);
    void play();
    void pause();
    void stop();
    bool isPaused() const;
    void seek(qint64 ms);
    qint64 position() const;
    void snapshot();

protected:
    void resizeGL(int w, int h) override;
    void paintGL() override;
    void keyPressEvent(QKeyEvent *) override;
private:
    std::shared_ptr<mdk::Player> player_;
};

3.5 widget.cpp

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);

}

Widget::~Widget()
{
    delete ui;
}


/*
工程: QMDK_Player
日期: 2021-03-31
作者: DS小龙哥
环境: win10 QT5.12.6 MinGW32
功能: 加载视频文件
*/
void Widget::on_pushButton_load_clicked()
{
    QString filename=QFileDialog::getOpenFileName(this,"选择打开的文件","C:/",tr("*.*"));
    ui->AV_player->setMedia(filename);
    ui->AV_player->play();
}


/*
工程: QMDK_Player
日期: 2021-03-31
作者: DS小龙哥
环境: win10 QT5.12.6 MinGW32
功能: 暂停/继续
*/
void Widget::on_pushButton_pause_clicked()
{
    ui->AV_player->pause();
}


/*
工程: QMDK_Player
日期: 2021-03-31
作者: DS小龙哥
环境: win10 QT5.12.6 MinGW32
功能: 重新播放
*/
void Widget::on_pushButton_reset_clicked()
{

}


/*
工程: QMDK_Player
日期: 2021-03-31
作者: DS小龙哥
环境: win10 QT5.12.6 MinGW32
功能: 播放
*/
void Widget::on_pushButton_play_clicked()
{
    ui->AV_player->play();
}


/*
工程: QMDK_Player
日期: 2021-03-31
作者: DS小龙哥
环境: win10 QT5.12.6 MinGW32
功能: 停止播放
*/
void Widget::on_pushButton_stop_clicked()
{
    ui->AV_player->stop();
}

3.6 widget.h代码

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QOpenGLWidget>
#include <memory>
#include "QMDKWidget.h"
#include <QFileDialog>

namespace mdk {
class Player;
}

QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget(QWidget *parent = nullptr);
    ~Widget();
private slots:
    void on_pushButton_load_clicked();

    void on_pushButton_pause_clicked();

    void on_pushButton_reset_clicked();

    void on_pushButton_play_clicked();

    void on_pushButton_stop_clicked();

private:
    Ui::Widget *ui;
};
#endif // WIDGET_H