[gst-cvs] qt-gstreamer: Add an example that demonstrates the usage of the appsrc and appsink wrappers .

[<gk...@ke...>]

Module: qt-gstreamer
Branch: master
Commit: 7b094779bcea21d5bd5e598c9f5ecd8bd46ae353
URL:    http://cgit.freedesktop.org/gstreamer/qt-gstreamer/commit/?id=7b094779bcea21d5bd5e598c9f5ecd8bd46ae353

Author: George Kiagiadakis <geo...@co...>
Date:   Mon Jan 17 18:42:07 2011 +0200

Add an example that demonstrates the usage of the appsrc and appsink wrappers.

---

 examples/CMakeLists.txt              |    1 +
 examples/appsink-src/CMakeLists.txt  |    9 +++
 examples/appsink-src/appsink-src.pro |   23 ++++++
 examples/appsink-src/main.cpp        |  131 ++++++++++++++++++++++++++++++++++
 src/main.dox                         |   13 ++++
 5 files changed, 177 insertions(+), 0 deletions(-)

diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 35bb0fc..fde340f 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -1,2 +1,3 @@
 add_subdirectory(echo)
 add_subdirectory(player)
+add_subdirectory(appsink-src)
diff --git a/examples/appsink-src/CMakeLists.txt b/examples/appsink-src/CMakeLists.txt
new file mode 100644
index 0000000..9985a38
--- /dev/null
+++ b/examples/appsink-src/CMakeLists.txt
@@ -0,0 +1,9 @@
+# This file serves as an example of how to use cmake with QtGStreamer.
+# It can be used for building this example either in the QtGStreamer source tree or standalone.
+
+find_package(QtGStreamer REQUIRED)
+include_directories(${QTGSTREAMER_INCLUDES})
+add_definitions(${QTGSTREAMER_DEFINITIONS})
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${QTGSTREAMER_FLAGS}")
+add_executable(appsink-src main.cpp)
+target_link_libraries(appsink-src ${QTGSTREAMER_UTILS_LIBRARIES})
diff --git a/examples/appsink-src/appsink-src.pro b/examples/appsink-src/appsink-src.pro
new file mode 100644
index 0000000..a666cee
--- /dev/null
+++ b/examples/appsink-src/appsink-src.pro
@@ -0,0 +1,23 @@
+# This is a qmake project file, provided as an example on how to use qmake with QtGStreamer.
+
+TEMPLATE = app
+TARGET = appsink-src
+
+# Tell qmake to use pkg-config to find QtGStreamer.
+CONFIG += link_pkgconfig
+
+# Now tell qmake to link to QtGStreamerUtils-0.10 and also use its include path and Cflags.
+PKGCONFIG += QtGStreamerUtils-0.10
+
+# Recommended if you are using g++ 4.5 or later. Must be removed for other compilers.
+#QMAKE_CXXFLAGS += -std=c++0x
+
+# Recommended, to avoid possible issues with the "emit" keyword
+# You can otherwise also define QT_NO_EMIT, but notice that this is not a documented Qt macro.
+DEFINES += QT_NO_KEYWORDS
+
+# This example has no GUI
+QT -= gui
+
+# Input
+SOURCES += main.cpp
diff --git a/examples/appsink-src/main.cpp b/examples/appsink-src/main.cpp
new file mode 100644
index 0000000..d15cddc
--- /dev/null
+++ b/examples/appsink-src/main.cpp
@@ -0,0 +1,131 @@
+/*
+    Copyright (C) 2011 Collabora Ltd. <in...@co...>
+      @author George Kiagiadakis <geo...@co...>
+
+    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 <iostream>
+#include <QtCore/QCoreApplication>
+#include <QGlib/Error>
+#include <QGlib/Connect>
+#include <QGst/Init>
+#include <QGst/Bus>
+#include <QGst/Pipeline>
+#include <QGst/Parse>
+#include <QGst/Message>
+#include <QGst/Utils/ApplicationSink>
+#include <QGst/Utils/ApplicationSource>
+
+
+class MySink : public QGst::Utils::ApplicationSink
+{
+public:
+    MySink(QGst::Utils::ApplicationSource *src)
+        : QGst::Utils::ApplicationSink(), m_src(src) {}
+
+protected:
+    virtual void eos()
+    {
+        m_src->endOfStream();
+    }
+
+    virtual QGst::FlowReturn newBuffer()
+    {
+        m_src->pushBuffer(pullBuffer());
+        return QGst::FlowOk;
+    }
+
+private:
+    QGst::Utils::ApplicationSource *m_src;
+};
+
+
+class Player : public QCoreApplication
+{
+public:
+    Player(int argc, char **argv);
+    ~Player();
+
+private:
+    void onBusMessage(const QGst::MessagePtr & message);
+
+private:
+    QGst::Utils::ApplicationSource m_src;
+    MySink m_sink;
+    QGst::PipelinePtr pipeline1;
+    QGst::PipelinePtr pipeline2;
+};
+
+Player::Player(int argc, char **argv)
+    : QCoreApplication(argc, argv), m_sink(&m_src)
+{
+    QGst::init(&argc, &argv);
+
+    if (argc <= 1) {
+        std::cerr << "Usage: " << argv[0] << " <audio_file>" << std::endl;
+        std::exit(1);
+    }
+
+    const char *caps = "audio/x-raw-int,channels=1,rate=8000,"
+                       "signed=(boolean)true,width=16,depth=16,endianness=1234";
+
+    /* source pipeline */
+    QString pipe1Descr = QString("filesrc location=\"%1\" ! "
+                                 "decodebin2 ! "
+                                 "audioconvert ! "
+                                 "audioresample ! "
+                                 "appsink name=\"mysink\" caps=\"%2\"").arg(argv[1], caps);
+    pipeline1 = QGst::Parse::launch(pipe1Descr).dynamicCast<QGst::Pipeline>();
+    m_sink.setElement(pipeline1->getElementByName("mysink"));
+    QGlib::connect(pipeline1->bus(), "message::error", this, &Player::onBusMessage);
+    pipeline1->bus()->addSignalWatch();
+
+    /* sink pipeline */
+    QString pipe2Descr = QString("appsrc name=\"mysrc\" caps=\"%1\" ! autoaudiosink").arg(caps);
+    pipeline2 = QGst::Parse::launch(pipe2Descr).dynamicCast<QGst::Pipeline>();
+    m_src.setElement(pipeline2->getElementByName("mysrc"));
+    QGlib::connect(pipeline2->bus(), "message", this, &Player::onBusMessage);
+    pipeline2->bus()->addSignalWatch();
+
+    /* start playing */
+    pipeline1->setState(QGst::StatePlaying);
+    pipeline2->setState(QGst::StatePlaying);
+}
+
+Player::~Player()
+{
+    pipeline1->setState(QGst::StateNull);
+    pipeline2->setState(QGst::StateNull);
+}
+
+void Player::onBusMessage(const QGst::MessagePtr & message)
+{
+    switch (message->type()) {
+    case QGst::MessageEos:
+        quit();
+        break;
+    case QGst::MessageError:
+        qCritical() << message.staticCast<QGst::ErrorMessage>()->error();
+        break;
+    default:
+        break;
+    }
+}
+
+
+int main(int argc, char **argv)
+{
+    Player p(argc, argv);
+    return p.exec();
+}
diff --git a/src/main.dox b/src/main.dox
index 02934c1..f2d701f 100644
--- a/src/main.dox
+++ b/src/main.dox
@@ -211,3 +211,16 @@
 /*! \example player/main.cpp
  * This is an example audio player using QtGStreamer
  */
+
+/*! \example appsink-src/main.cpp
+ * This example demonstrates how to use QGst::Utils::ApplicationSource and
+ * QGst::Utils::ApplicationSink to create a custom source and sink respectively.
+ *
+ * In this example, we have two pipelines, one pipeline that gets data from a file,
+ * decodes the audio stream and sends the audio buffers to appsink, and a second
+ * pipeline that gets data from appsrc and pushes them to an audio sink. Appsink
+ * from the first pipeline is linked with appsrc from the second pipeline in our
+ * code, by listening to appsink's newBuffer() signal, getting the buffer
+ * and pushing it to appsrc with the pushBuffer() method. The result is a choppy
+ * audio player.
+ */