appsrc

src/gstreamerextras/gstreamerextras.pro

 TARGET = QtGstreamerExtras
 
-QT = multimediagsttools_private
+QT = multimediagsttools-private
 
 PUBLIC_HEADERS += \
     qgstreamerpipeline.h \
-    qgstreamerplaybin.h
+    qgstreamerplaybin.h \
+    qgstreamerappsrc.h
 
 PRIVATE_HEADERS += \
     qgstreamerpipeline_p.h
 
 SOURCES += \
     qgstreamerplaybin.cpp \
-    qgstreamerpipeline.cpp
+    qgstreamerpipeline.cpp \
+    qgstreamerappsrc.cpp
 
 CONFIG += simd optimize_full
 

src/gstreamerextras/qgstreamerappsrc.cpp

+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qgstreamerappsrc.h"
+#include "qgstreamerpipeline_p.h"
+#include <private/qgstutils_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QGstreamerAppSrcPrivate
+{
+    Q_DECLARE_PUBLIC(QGstreamerAppSrc)
+
+public:
+    QGstreamerAppSrcPrivate(GstElement *src, QGstreamerAppSrc *q)
+        : appsrc(src)
+        , q_ptr(q)
+    {
+    }
+
+    void restart(QVideoFrame &frame);
+
+private:
+    GstElement *appsrc = nullptr;
+    QGstreamerAppSrc *q_ptr = nullptr;
+    int timerMsec = 30;
+    int timerId = 0;
+    QSize size;
+};
+
+void QGstreamerAppSrcPrivate::restart(QVideoFrame &frame)
+{
+    QList<QVideoFrame::PixelFormat> cc;
+    cc << frame.pixelFormat();
+    GstCaps *caps = QGstUtils::capsForFormats(cc);
+    gst_caps_set_simple(
+        caps,
+        "framerate", GST_TYPE_FRACTION , 30, 1,
+        "width", G_TYPE_INT, frame.width(),
+        "height", G_TYPE_INT, frame.height(),
+        NULL);
+
+    g_object_set(G_OBJECT(appsrc), "caps", caps, NULL);
+    gst_caps_unref(caps);
+}
+
+static void start_feed(GstElement *pipeline, guint size, QGstreamerAppSrc *q)
+{
+    Q_UNUSED(pipeline);
+    Q_UNUSED(size);
+    QMetaObject::invokeMethod(q, "startFeed", Qt::QueuedConnection);
+}
+
+static void stop_feed(GstElement *pipeline, QGstreamerAppSrc *q)
+{
+    Q_UNUSED(pipeline);
+    QMetaObject::invokeMethod(q, "stopFeed", Qt::QueuedConnection);
+}
+
+void QGstreamerAppSrc::startFeed()
+{
+    Q_D(QGstreamerAppSrc);
+
+    if (d->timerId)
+        return;
+
+    d->timerId = startTimer(d->timerMsec);
+}
+
+void QGstreamerAppSrc::stopFeed()
+{
+    Q_D(QGstreamerAppSrc);
+
+    if (!d->timerId)
+        return;
+
+    killTimer(d->timerId);
+    d->timerId = 0;
+}
+
+QVideoFrame QGstreamerAppSrc::readFrame() const
+{
+    return QVideoFrame();
+}
+
+void QGstreamerAppSrc::timerEvent(QTimerEvent *event)
+{
+    Q_D(QGstreamerAppSrc);
+
+    if (event->timerId() != d->timerId)
+        return;
+
+    QVideoFrame frame = readFrame();
+    if (!frame.isValid() || !frame.map(QAbstractVideoBuffer::ReadOnly))
+        return;
+
+    if (d->size != frame.size())
+        d->restart(frame);
+
+    auto app_buffer = gst_buffer_new();
+    int size = frame.bytesPerLine() * frame.height();
+    auto mem = gst_allocator_alloc (NULL, size, NULL);
+
+    GstMapInfo info;
+    gst_memory_map(mem, &info, GST_MAP_WRITE);
+    memcpy(info.data, frame.bits(), size);
+    gst_memory_unmap(mem, &info);
+
+    gst_buffer_append_memory(app_buffer, mem);
+    gst_buffer_set_size(app_buffer, size);
+
+    GstFlowReturn ret;
+    g_signal_emit_by_name (d->appsrc, "push-buffer", app_buffer, &ret);
+    if (ret != GST_FLOW_OK) {
+        qWarning() << "Error has occured while pushing a buffer";
+        stopFeed();
+    }
+
+    gst_buffer_unref(app_buffer);
+    frame.unmap();
+}
+
+QGstreamerAppSrc::QGstreamerAppSrc(GstElement *appsrc, QObject *parent)
+    : QObject(parent)
+    , d_ptr(new QGstreamerAppSrcPrivate(appsrc, this))
+{
+    g_signal_connect(appsrc, "need-data", G_CALLBACK(start_feed), this);
+    g_signal_connect(appsrc, "enough-data", G_CALLBACK(stop_feed), this);    
+}
+
+QGstreamerAppSrc::~QGstreamerAppSrc()
+{
+    delete d_ptr;
+}
+
+#include "moc_qgstreamerappsrc.cpp"
+
+QT_END_NAMESPACE

src/gstreamerextras/qgstreamerappsrc.h

+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QGSTREAMERAPPSRC_H
+#define QGSTREAMERAPPSRC_H
+
+#include <QVideoFrame>
+#include <gst/gst.h>
+
+QT_BEGIN_NAMESPACE
+
+class QGstreamerAppSrcPrivate;
+class Q_MULTIMEDIA_EXPORT QGstreamerAppSrc : public QObject
+{
+    Q_OBJECT
+public:
+    QGstreamerAppSrc(GstElement *appsrc, QObject *parent = nullptr);
+    ~QGstreamerAppSrc();
+
+protected:
+    virtual QVideoFrame readFrame() const;
+
+private Q_SLOTS:
+    void startFeed();
+    void stopFeed();
+
+private:
+    void timerEvent(QTimerEvent *event) override;
+
+    Q_DISABLE_COPY(QGstreamerAppSrc)
+    Q_DECLARE_PRIVATE(QGstreamerAppSrc)
+
+    QGstreamerAppSrcPrivate *d_ptr = nullptr;
+};
+
+QT_END_NAMESPACE
+
+#endif // QGSTREAMERAPPSRC_H