Add a new "recorder" example.

5 files changed, 607 insertions, 0 deletions

diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 27b62bb..acbf38d 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -1,2 +1,3 @@
 add_subdirectory(player)
 add_subdirectory(appsink-src)
+add_subdirectory(recorder)
diff --git a/examples/examples.dox b/examples/examples.dox
index f983c18..e7fb4a3 100644
--- a/examples/examples.dox
+++ b/examples/examples.dox
@@ -32,3 +32,21 @@
  * and pushing it to appsrc with the pushBuffer() method. The result is a choppy
  * audio player.
  */
+
+/*! \example recorder/main.cpp
+ * This is a recording application that takes audio from a microphone
+ * and video from either a camera or the X11 screen, encodes them with
+ * theora and speex and saves the result in a file.
+ *
+ * The intention of this example is to show how simple it is to perform such
+ * complex tasks with GStreamer and how easy it is to change the functionality
+ * of the program by changing just one element (with autovideosrc it will
+ * do a webcam recording, but with ximagesrc it will do a screencast).
+ *
+ * Tasks demonstrated in this example include:
+ * \li How to create and link elements manually.
+ * \li How to create and link elements using a pipeline description.
+ * \li How to use the QGst::PropertyProbe interface.
+ * \li How to handle bus messages.
+ * \li Others...
+ */
diff --git a/examples/recorder/CMakeLists.txt b/examples/recorder/CMakeLists.txt
new file mode 100644
index 0000000..8352a3f
--- /dev/null
+++ b/examples/recorder/CMakeLists.txt
@@ -0,0 +1,6 @@
+include_directories(${QTGSTREAMER_INCLUDES} ${CMAKE_CURRENT_BINARY_DIR})
+add_definitions(${QTGSTREAMER_DEFINITIONS})
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${QTGSTREAMER_FLAGS}")
+qt4_wrap_ui(recorder_UI_SRCS recorder.ui)
+automoc4_add_executable(recorder main.cpp ${recorder_UI_SRCS})
+target_link_libraries(recorder ${QTGSTREAMER_LIBRARIES} ${QT_QTGUI_LIBRARY})
diff --git a/examples/recorder/main.cpp b/examples/recorder/main.cpp
new file mode 100644
index 0000000..5ec00d0
--- /dev/null
+++ b/examples/recorder/main.cpp
@@ -0,0 +1,325 @@
+/*
+    Copyright (C) 2011 Collabora Ltd.
+      @author George Kiagiadakis <george.kiagiadakis@collabora.co.uk>
+
+    This library is free software; you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published
+    by the Free Software Foundation; either version 2.1 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include "ui_recorder.h"
+
+#include <QtCore/QDir>
+#include <QtGui/QApplication>
+#include <QtGui/QDialog>
+#include <QtGui/QMessageBox>
+
+#include <QGlib/Error>
+#include <QGlib/Connect>
+#include <QGst/Init>
+#include <QGst/ElementFactory>
+#include <QGst/ChildProxy>
+#include <QGst/PropertyProbe>
+#include <QGst/Pipeline>
+#include <QGst/Pad>
+#include <QGst/Event>
+#include <QGst/Message>
+#include <QGst/Bus>
+
+#ifdef Q_WS_X11
+# include <QtGui/QX11Info>
+#endif
+
+
+class Recorder : public QDialog
+{
+    Q_OBJECT
+public:
+    Recorder(QWidget *parent = 0);
+
+private:
+    enum Device { AudioSrc, VideoSrc };
+    void findDevices(Device device);
+    void probeForDevices(const QGst::PropertyProbePtr & propertyProbe);
+
+    QGst::BinPtr createAudioSrcBin();
+    QGst::BinPtr createVideoSrcBin();
+
+    void start();
+    void stop();
+
+    void onBusMessage(const QGst::MessagePtr & message);
+
+private Q_SLOTS:
+    void on_startStopButton_clicked();
+
+private:
+    Ui::Recorder m_ui;
+    QGst::PropertyProbePtr m_audioProbe;
+    QGst::PropertyProbePtr m_videoProbe;
+    QGst::PipelinePtr m_pipeline;
+};
+
+Recorder::Recorder(QWidget *parent)
+    : QDialog(parent)
+{
+    m_ui.setupUi(this);
+
+    //setup the device combo boxes
+    findDevices(AudioSrc);
+    findDevices(VideoSrc);
+
+    QGst::ElementFactoryPtr ximagesrc = QGst::ElementFactory::find("ximagesrc");
+    if (!ximagesrc) {
+        //if we don't have ximagesrc, disable the choice to use it
+        m_ui.videoSourceComboBox->removeItem(1);
+    } else {
+#ifdef Q_WS_X11
+        //setup the default screen to be the screen that this dialog is shown
+        m_ui.displayNumSpinBox->setValue(QX11Info::appScreen());
+#endif
+    }
+
+    //set default output file
+    m_ui.outputFileEdit->setText(QDir::currentPath() + QDir::separator() + "out.ogv");
+}
+
+void Recorder::findDevices(Device device)
+{
+    const char *srcElementName = (device == AudioSrc) ? "autoaudiosrc" : "autovideosrc";
+    QGst::ElementPtr src = QGst::ElementFactory::make(srcElementName);
+
+    if (!src) {
+        QMessageBox::critical(this, tr("Error"),
+                              tr("Failed to create element \"%1\". Make sure you have "
+                                 "gstreamer-plugins-good installed").arg(srcElementName));
+        return;
+    }
+
+    QGst::PropertyProbePtr propertyProbe;
+
+    //autoaudiosrc and autovideosrc implement the child proxy interface
+    //and create the correct child element when they go to the READY state
+    src->setState(QGst::StateReady);
+    QGst::ChildProxyPtr childProxy = src.dynamicCast<QGst::ChildProxy>();
+    if (childProxy && childProxy->childrenCount() > 0) {
+        //the actual source is the first child
+        //this source usually implements the property probe interface
+        propertyProbe = childProxy->childByIndex(0).dynamicCast<QGst::PropertyProbe>();
+    }
+    //we got a reference to the underlying propertyProbe, so we don't need src anymore.
+    src->setState(QGst::StateNull);
+
+    //Most sources and sinks have a "device" property which supports probe
+    //and probing it returns all the available devices on the system.
+    //Here we try to make use of that to list the system's devices
+    //and if it fails, we just leave the source to use its default device.
+    if (propertyProbe && propertyProbe->propertySupportsProbe("device")) {
+        ((device == AudioSrc) ? m_audioProbe : m_videoProbe) = propertyProbe;
+        probeForDevices(propertyProbe);
+
+        //this signal will notify us when devices change
+        QGlib::connect(propertyProbe, "probe-needed",
+                       this, &Recorder::probeForDevices, QGlib::PassSender);
+    } else {
+        QComboBox *box = (device == AudioSrc) ? m_ui.audioDeviceComboBox : m_ui.videoDeviceComboBox;
+        box->addItem(tr("Default"));
+    }
+}
+
+void Recorder::probeForDevices(const QGst::PropertyProbePtr & propertyProbe)
+{
+    QComboBox *box = (propertyProbe == m_audioProbe) ?
+                     m_ui.audioDeviceComboBox : m_ui.videoDeviceComboBox;
+
+    box->clear();
+    box->addItem(tr("Default"));
+
+    //get a list of devices that the element supports
+    QList<QGlib::Value> devices = propertyProbe->probeAndGetValues("device");
+
+    Q_FOREACH(const QGlib::Value & device, devices) {
+        //set the element's device to the current device and retrieve its
+        //human-readable name through the "device-name" property
+        propertyProbe->setProperty("device", device);
+        QString deviceName = propertyProbe->property("device-name").toString();
+
+        //add the device on the combobox
+        box->addItem(QString("%1 (%2)").arg(deviceName, device.toString()),
+                     device.toString());
+    }
+}
+
+QGst::BinPtr Recorder::createAudioSrcBin()
+{
+    QGst::BinPtr audioBin;
+
+    try {
+        audioBin = QGst::Bin::fromDescription("autoaudiosrc name=\"audiosrc\" ! audioconvert ! "
+                                              "audioresample ! audiorate ! speexenc ! queue");
+    } catch (const QGlib::Error & error) {
+        qCritical() << "Failed to create audio source bin:" << error;
+        return QGst::BinPtr();
+    }
+
+    //set the source's properties
+    QVariant device = m_ui.audioDeviceComboBox->itemData(m_ui.audioDeviceComboBox->currentIndex());
+    if (device.isValid()) {
+        QGst::ElementPtr src = audioBin->getElementByName("audiosrc");
+
+        //autoaudiosrc creates the actual source in the READY state
+        src->setState(QGst::StateReady);
+
+        QGst::ChildProxyPtr childProxy = src.dynamicCast<QGst::ChildProxy>();
+        if (childProxy && childProxy->childrenCount() > 0) {
+            //the actual source is the first child
+            QGst::ObjectPtr realSrc = childProxy->childByIndex(0);
+            realSrc->setProperty("device", device.toString());
+        }
+    }
+
+    return audioBin;
+}
+
+QGst::BinPtr Recorder::createVideoSrcBin()
+{
+    QGst::BinPtr videoBin;
+
+    try {
+        if (m_ui.videoSourceComboBox->currentIndex() == 0) { //camera
+            videoBin = QGst::Bin::fromDescription("autovideosrc name=\"videosrc\" ! "
+                                                  "ffmpegcolorspace ! theoraenc ! queue");
+        } else { //screencast
+            videoBin = QGst::Bin::fromDescription("ximagesrc name=\"videosrc\" ! "
+                                                  "ffmpegcolorspace ! theoraenc ! queue");
+        }
+    } catch (const QGlib::Error & error) {
+        qCritical() << "Failed to create video source bin:" << error;
+        return QGst::BinPtr();
+    }
+
+    //set the source's properties
+    if (m_ui.videoSourceComboBox->currentIndex() == 0) { //camera
+        QVariant device = m_ui.videoDeviceComboBox->itemData(m_ui.videoDeviceComboBox->currentIndex());
+        if (device.isValid()) {
+            QGst::ElementPtr src = videoBin->getElementByName("videosrc");
+
+            //autovideosrc creates the actual source in the READY state
+            src->setState(QGst::StateReady);
+
+            QGst::ChildProxyPtr childProxy = src.dynamicCast<QGst::ChildProxy>();
+            if (childProxy && childProxy->childrenCount() > 0) {
+                //the actual source is the first child
+                QGst::ObjectPtr realSrc = childProxy->childByIndex(0);
+                realSrc->setProperty("device", device.toString());
+            }
+        }
+    } else { //screencast
+        videoBin->getElementByName("videosrc")->setProperty("screen-num", m_ui.displayNumSpinBox->value());
+    }
+
+    return videoBin;
+}
+
+void Recorder::start()
+{
+    QGst::BinPtr audioSrcBin = createAudioSrcBin();
+    QGst::BinPtr videoSrcBin = createVideoSrcBin();
+    QGst::ElementPtr mux = QGst::ElementFactory::make("oggmux");
+    QGst::ElementPtr sink = QGst::ElementFactory::make("filesink");
+
+    if (!audioSrcBin || !videoSrcBin || !mux || !sink) {
+        QMessageBox::critical(this, tr("Error"), tr("One or more elements could not be created. "
+                              "Verify that you have all the necessary element plugins installed."));
+        return;
+    }
+
+    sink->setProperty("location", m_ui.outputFileEdit->text());
+
+    m_pipeline = QGst::Pipeline::create();
+    m_pipeline->add(audioSrcBin);
+    m_pipeline->add(videoSrcBin);
+    m_pipeline->add(mux);
+    m_pipeline->add(sink);
+
+    //link elements
+    QGst::PadPtr audioPad = mux->getRequestPad("sink_%d");
+    audioSrcBin->getStaticPad("src")->link(audioPad);
+
+    QGst::PadPtr videoPad = mux->getRequestPad("sink_%d");
+    videoSrcBin->getStaticPad("src")->link(videoPad);
+
+    mux->link(sink);
+
+    //connect the bus
+    m_pipeline->bus()->addSignalWatch();
+    QGlib::connect(m_pipeline->bus(), "message", this, &Recorder::onBusMessage);
+
+    //go!
+    m_pipeline->setState(QGst::StatePlaying);
+    m_ui.startStopButton->setText(tr("Stop recording"));
+}
+
+void Recorder::stop()
+{
+    //stop recording
+    m_pipeline->setState(QGst::StateNull);
+
+    //clear the pointer, destroying the pipeline as its reference count drops to zero.
+    m_pipeline.clear();
+
+    //restore the button's text
+    m_ui.startStopButton->setText(tr("Start recording"));
+}
+
+void Recorder::onBusMessage(const QGst::MessagePtr & message)
+{
+    switch (message->type()) {
+    case QGst::MessageEos:
+        //got end-of-stream - stop the pipeline
+        stop();
+        break;
+    case QGst::MessageError:
+        //check if the pipeline exists before destroying it,
+        //as we might get multiple error messages
+        if (m_pipeline) {
+            stop();
+        }
+        QMessageBox::critical(this, tr("Pipeline Error"),
+                              message.staticCast<QGst::ErrorMessage>()->error().message());
+        break;
+    default:
+        break;
+    }
+}
+
+void Recorder::on_startStopButton_clicked()
+{
+    if (m_pipeline) { //pipeline exists - destroy it
+        //send an end-of-stream event to flush metadata and cause an EosMessage to be delivered
+        m_pipeline->sendEvent(QGst::EosEvent::create());
+    } else { //pipeline doesn't exist - start a new one
+        start();
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    QApplication app(argc, argv);
+    QGst::init(&argc, &argv);
+
+    Recorder r;
+    r.show();
+
+    return app.exec();
+}
+
+#include "recorder.moc"
diff --git a/examples/recorder/recorder.ui b/examples/recorder/recorder.ui
new file mode 100644
index 0000000..7e750db
--- /dev/null
+++ b/examples/recorder/recorder.ui
@@ -0,0 +1,257 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>Recorder</class>
+ <widget class="QDialog" name="Recorder">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>306</width>
+    <height>284</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>QtGStreamer recorder example</string>
+  </property>
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="0" column="0" colspan="3">
+    <widget class="QGroupBox" name="audioSourceGroupBox">
+     <property name="title">
+      <string>Audio source</string>
+     </property>
+     <layout class="QVBoxLayout" name="verticalLayout">
+      <item>
+       <layout class="QHBoxLayout" name="horizontalLayout_3">
+        <item>
+         <widget class="QLabel" name="audioSourceLabel">
+          <property name="sizePolicy">
+           <sizepolicy hsizetype="Minimum" vsizetype="Preferred">
+            <horstretch>0</horstretch>
+            <verstretch>0</verstretch>
+           </sizepolicy>
+          </property>
+          <property name="text">
+           <string>Audio source:</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QComboBox" name="audioSourceComboBox">
+          <item>
+           <property name="text">
+            <string>Microphone</string>
+           </property>
+          </item>
+         </widget>
+        </item>
+       </layout>
+      </item>
+      <item>
+       <widget class="QStackedWidget" name="audioSourcePropertiesWidget">
+        <property name="currentIndex">
+         <number>0</number>
+        </property>
+        <widget class="QWidget" name="microphonePage">
+         <layout class="QHBoxLayout" name="horizontalLayout_2">
+          <item>
+           <widget class="QLabel" name="audioDeviceLabel">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Minimum" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>Device:</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QComboBox" name="audioDeviceComboBox"/>
+          </item>
+         </layout>
+        </widget>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item row="1" column="0" colspan="3">
+    <widget class="QGroupBox" name="videoSourceGroupBox">
+     <property name="title">
+      <string>Video source</string>
+     </property>
+     <layout class="QVBoxLayout" name="verticalLayout_2">
+      <item>
+       <layout class="QHBoxLayout" name="horizontalLayout_4">
+        <item>
+         <widget class="QLabel" name="videoSourceLabel">
+          <property name="sizePolicy">
+           <sizepolicy hsizetype="Minimum" vsizetype="Preferred">
+            <horstretch>0</horstretch>
+            <verstretch>0</verstretch>
+           </sizepolicy>
+          </property>
+          <property name="text">
+           <string>Video source:</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QComboBox" name="videoSourceComboBox">
+          <item>
+           <property name="text">
+            <string>Camera</string>
+           </property>
+          </item>
+          <item>
+           <property name="text">
+            <string>Screencast (X11)</string>
+           </property>
+          </item>
+         </widget>
+        </item>
+       </layout>
+      </item>
+      <item>
+       <widget class="QStackedWidget" name="videoSourcePropertiesWidget">
+        <property name="currentIndex">
+         <number>0</number>
+        </property>
+        <widget class="QWidget" name="cameraPage">
+         <layout class="QHBoxLayout" name="horizontalLayout_5">
+          <item>
+           <widget class="QLabel" name="videoDeviceLabel">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Minimum" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>Device:</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QComboBox" name="videoDeviceComboBox"/>
+          </item>
+         </layout>
+        </widget>
+        <widget class="QWidget" name="screencastPage">
+         <layout class="QHBoxLayout" name="horizontalLayout_6">
+          <item>
+           <widget class="QLabel" name="displayNumLabel">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Minimum" vsizetype="Preferred">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="text">
+             <string>Display number:</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QSpinBox" name="displayNumSpinBox">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+           </widget>
+          </item>
+         </layout>
+        </widget>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item row="2" column="0" colspan="3">
+    <layout class="QHBoxLayout" name="horizontalLayout">
+     <item>
+      <widget class="QLabel" name="outputFileLabel">
+       <property name="text">
+        <string>Output file (ogg):</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QLineEdit" name="outputFileEdit"/>
+     </item>
+    </layout>
+   </item>
+   <item row="3" column="0">
+    <spacer name="horizontalSpacer">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>76</width>
+       <height>20</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+   <item row="3" column="1">
+    <widget class="QPushButton" name="startStopButton">
+     <property name="text">
+      <string>Start recording</string>
+     </property>
+    </widget>
+   </item>
+   <item row="3" column="2">
+    <spacer name="horizontalSpacer_2">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>87</width>
+       <height>20</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections>
+  <connection>
+   <sender>audioSourceComboBox</sender>
+   <signal>currentIndexChanged(int)</signal>
+   <receiver>audioSourcePropertiesWidget</receiver>
+   <slot>setCurrentIndex(int)</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>305</x>
+     <y>52</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>231</x>
+     <y>73</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>videoSourceComboBox</sender>
+   <signal>currentIndexChanged(int)</signal>
+   <receiver>videoSourcePropertiesWidget</receiver>
+   <slot>setCurrentIndex(int)</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>266</x>
+     <y>172</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>220</x>
+     <y>191</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>