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// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qgstreamervideooutput_p.h"
#include <QtMultimedia/qvideosink.h>
#include <QtCore/qloggingcategory.h>
#include <common/qgstreamervideosink_p.h>
#include <common/qgstsubtitlesink_p.h>
Q_STATIC_LOGGING_CATEGORY(qLcMediaVideoOutput, "qt.multimedia.videooutput");
QT_BEGIN_NAMESPACE
static QGstElement makeVideoConvertScale(const char *name)
{
QGstElementFactoryHandle factory = QGstElement::findFactory("videoconvertscale");
if (factory) // videoconvertscale is only available in gstreamer 1.20
return QGstElement::createFromFactory(factory, name);
return QGstBin::createFromPipelineDescription("videoconvert ! videoscale", name,
/*ghostUnlinkedPads=*/true);
}
q23::expected<QGstreamerVideoOutput *, QString> QGstreamerVideoOutput::create(QObject *parent)
{
QGstElementFactoryHandle factory = QGstElement::findFactory("videoconvertscale");
static std::optional<QString> elementCheck = []() -> std::optional<QString> {
std::optional<QString> error = qGstErrorMessageIfElementsNotAvailable("fakesink", "queue");
if (error)
return error;
QGstElementFactoryHandle factory = QGstElement::findFactory("videoconvertscale");
if (factory)
return std::nullopt;
return qGstErrorMessageIfElementsNotAvailable("videoconvert", "videoscale");
}();
if (elementCheck)
return q23::unexpected{ *elementCheck };
return new QGstreamerVideoOutput(parent);
}
QGstreamerVideoOutput::QGstreamerVideoOutput(QObject *parent)
: QObject(parent),
m_outputBin{
QGstBin::create("videoOutput"),
},
m_videoQueue{
QGstElement::createFromFactory("queue", "videoQueue"),
},
m_videoConvertScale{
makeVideoConvertScale("videoConvertScale"),
},
m_videoSink{
QGstElement::createFromFactory("fakesink", "fakeVideoSink"),
}
{
m_videoSink.set("sync", true);
m_outputBin.add(m_videoQueue, m_videoConvertScale, m_videoSink);
qLinkGstElements(m_videoQueue, m_videoConvertScale, m_videoSink);
m_subtitleSink = QGstSubtitleSink::createSink(this);
m_outputBin.addGhostPad(m_videoQueue, "sink");
}
QGstreamerVideoOutput::~QGstreamerVideoOutput()
{
QObject::disconnect(m_subtitleConnection);
m_outputBin.setStateSync(GST_STATE_NULL);
}
void QGstreamerVideoOutput::setVideoSink(QGstreamerRelayVideoSink *sink)
{
using namespace std::chrono_literals;
if (sink == m_gstVideoSink)
return;
m_gstVideoSink = sink;
if (m_gstVideoSink) {
m_gstVideoSink->setActive(m_isActive);
if (m_nativeSize.isValid())
m_gstVideoSink->setNativeSize(m_nativeSize);
}
QGstElement videoSink;
if (m_gstVideoSink) {
videoSink = m_gstVideoSink->gstSink();
} else {
videoSink = QGstElement::createFromFactory("fakesink", "fakevideosink");
Q_ASSERT(videoSink);
videoSink.set("sync", true);
}
QObject::disconnect(m_subtitleConnection);
if (sink) {
m_subtitleConnection = QObject::connect(this, &QGstreamerVideoOutput::subtitleChanged, sink,
[sink](const QString &subtitle) {
sink->setSubtitleText(subtitle);
});
sink->setSubtitleText(m_lastSubtitleString);
}
if (m_videoSink == videoSink)
return;
m_videoConvertScale.src().modifyPipelineInIdleProbe([&] {
if (m_videoSink)
m_outputBin.stopAndRemoveElements(m_videoSink);
m_videoSink = std::move(videoSink);
m_outputBin.add(m_videoSink);
qLinkGstElements(m_videoConvertScale, m_videoSink);
GstEvent *event = gst_event_new_reconfigure();
gst_element_send_event(m_videoSink.element(), event);
m_videoSink.syncStateWithParent();
});
qCDebug(qLcMediaVideoOutput) << "sinkChanged" << m_videoSink.name();
m_videoConvertScale.dumpPipelineGraph(m_videoSink.name().constData());
}
void QGstreamerVideoOutput::setActive(bool isActive)
{
if (m_isActive == isActive)
return;
m_isActive = isActive;
if (m_gstVideoSink)
m_gstVideoSink->setActive(isActive);
}
void QGstreamerVideoOutput::updateNativeSize()
{
if (!m_gstVideoSink)
return;
m_gstVideoSink->setNativeSize(qRotatedFrameSize(m_nativeSize, m_rotation));
}
void QGstreamerVideoOutput::setIsPreview()
{
// configures the queue to be fast and lightweight for camera preview
// also avoids blocking the queue in case we have an encodebin attached to the tee as well
m_videoQueue.set("leaky", 2 /*downstream*/);
m_videoQueue.set("silent", true);
m_videoQueue.set("max-size-buffers", int(1));
m_videoQueue.set("max-size-bytes", unsigned(0));
m_videoQueue.set("max-size-time", uint64_t(0));
}
void QGstreamerVideoOutput::flushSubtitles()
{
if (m_subtitleSink) {
auto pad = m_subtitleSink.staticPad("sink");
auto *event = gst_event_new_flush_start();
pad.sendEvent(event);
event = gst_event_new_flush_stop(false);
pad.sendEvent(event);
}
}
void QGstreamerVideoOutput::setNativeSize(QSize sz)
{
m_nativeSize = sz;
updateNativeSize();
}
void QGstreamerVideoOutput::setRotation(QtVideo::Rotation rot)
{
m_rotation = rot;
updateNativeSize();
}
void QGstreamerVideoOutput::updateSubtitle(QString string)
{
// GStreamer thread
QMetaObject::invokeMethod(this, [this, string = std::move(string)]() mutable {
m_lastSubtitleString = string;
Q_EMIT subtitleChanged(std::move(string));
});
}
QT_END_NAMESPACE
#include "moc_qgstreamervideooutput_p.cpp"