Android: support non OpenGL video surfaces for the camera.

QCamera can now pass raw frame data to its QAbstractVideoSurface.
The now deprecated Android camera API we're using doesn't allow to
get frame data without also displaying the frames in a SurfaceView
or a SurfaceTexture. To work around that, an invisible dummy
SurfaceView is used.
This allows to retrieve frames in the NV21, YV12, YUY2 or RGB565
formats, depending on the Android version and on the device.

Task-number: QTBUG-35416
Change-Id: I77b4f50505c3b91efb4b2288a57f50398922c0db
Reviewed-by: Christian Stromme <christian.stromme@theqtcompany.com>
Reviewed-by: Yoann Lopes <yoann.lopes@theqtcompany.com>

1 files changed, 204 insertions, 0 deletions

diff --git a/src/plugins/android/src/wrappers/jni/androidsurfaceview.cpp b/src/plugins/android/src/wrappers/jni/androidsurfaceview.cpp
new file mode 100644
index 000000000..67560baf4
--- /dev/null
+++ b/src/plugins/android/src/wrappers/jni/androidsurfaceview.cpp
@@ -0,0 +1,204 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://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 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "androidsurfaceview.h"
+
+#include <QtCore/private/qjnihelpers_p.h>
+#include <QtCore/qcoreapplication.h>
+#include <QtCore/qvector.h>
+#include <QtCore/qdebug.h>
+#include <QtCore/qmutex.h>
+#include <QtGui/qwindow.h>
+
+QT_BEGIN_NAMESPACE
+
+static const char QtSurfaceHolderCallbackClassName[] = "org/qtproject/qt5/android/multimedia/QtSurfaceHolderCallback";
+typedef QVector<AndroidSurfaceHolder *> SurfaceHolders;
+Q_GLOBAL_STATIC(SurfaceHolders, surfaceHolders)
+Q_GLOBAL_STATIC(QMutex, shLock)
+
+AndroidSurfaceHolder::AndroidSurfaceHolder(QJNIObjectPrivate object)
+    : m_surfaceHolder(object)
+    , m_surfaceCreated(false)
+{
+    if (!m_surfaceHolder.isValid())
+        return;
+
+    {
+        QMutexLocker locker(shLock);
+        surfaceHolders->append(this);
+    }
+
+    QJNIObjectPrivate callback(QtSurfaceHolderCallbackClassName, "(J)V", reinterpret_cast<jlong>(this));
+    m_surfaceHolder.callMethod<void>("addCallback",
+                                     "(Landroid/view/SurfaceHolder$Callback;)V",
+                                     callback.object());
+}
+
+AndroidSurfaceHolder::~AndroidSurfaceHolder()
+{
+    QMutexLocker locker(shLock);
+    const int i = surfaceHolders->indexOf(this);
+    if (Q_UNLIKELY(i == -1))
+        return;
+
+    surfaceHolders->remove(i);
+}
+
+jobject AndroidSurfaceHolder::surfaceHolder() const
+{
+    return m_surfaceHolder.object();
+}
+
+bool AndroidSurfaceHolder::isSurfaceCreated() const
+{
+    QMutexLocker locker(shLock);
+    return m_surfaceCreated;
+}
+
+void AndroidSurfaceHolder::handleSurfaceCreated(JNIEnv*, jobject, jlong id)
+{
+    QMutexLocker locker(shLock);
+    const int i = surfaceHolders->indexOf(reinterpret_cast<AndroidSurfaceHolder *>(id));
+    if (Q_UNLIKELY(i == -1))
+        return;
+
+    (*surfaceHolders)[i]->m_surfaceCreated = true;
+    Q_EMIT (*surfaceHolders)[i]->surfaceCreated();
+}
+
+void AndroidSurfaceHolder::handleSurfaceDestroyed(JNIEnv*, jobject, jlong id)
+{
+    QMutexLocker locker(shLock);
+    const int i = surfaceHolders->indexOf(reinterpret_cast<AndroidSurfaceHolder *>(id));
+    if (Q_UNLIKELY(i == -1))
+        return;
+
+    (*surfaceHolders)[i]->m_surfaceCreated = false;
+}
+
+bool AndroidSurfaceHolder::initJNI(JNIEnv *env)
+{
+    jclass clazz = QJNIEnvironmentPrivate::findClass(QtSurfaceHolderCallbackClassName,
+                                                     env);
+
+    static const JNINativeMethod methods[] = {
+        {"notifySurfaceCreated", "(J)V", (void *)AndroidSurfaceHolder::handleSurfaceCreated},
+        {"notifySurfaceDestroyed", "(J)V", (void *)AndroidSurfaceHolder::handleSurfaceDestroyed}
+    };
+
+    if (clazz && env->RegisterNatives(clazz,
+                                      methods,
+                                      sizeof(methods) / sizeof(methods[0])) != JNI_OK) {
+            return false;
+    }
+
+    return true;
+}
+
+AndroidSurfaceView::AndroidSurfaceView()
+    : m_window(0)
+    , m_surfaceHolder(0)
+    , m_pendingVisible(-1)
+{
+    setAutoDelete(false);
+    QtAndroidPrivate::runOnUiThread(this, QJNIEnvironmentPrivate());
+}
+
+AndroidSurfaceView::~AndroidSurfaceView()
+{
+    delete m_surfaceHolder;
+    delete m_window;
+}
+
+AndroidSurfaceHolder *AndroidSurfaceView::holder() const
+{
+    return m_surfaceHolder;
+}
+
+void AndroidSurfaceView::setVisible(bool v)
+{
+    if (m_window)
+        m_window->setVisible(v);
+    else
+        m_pendingVisible = int(v);
+}
+
+void AndroidSurfaceView::setGeometry(int x, int y, int width, int height)
+{
+    if (m_window)
+        m_window->setGeometry(x, y, width, height);
+    else
+        m_pendingGeometry = QRect(x, y, width, height);
+}
+
+bool AndroidSurfaceView::event(QEvent *e)
+{
+    if (e->type() == QEvent::User) {
+        Q_ASSERT(m_surfaceView.isValid());
+
+        QJNIObjectPrivate holder = m_surfaceView.callObjectMethod("getHolder",
+                                                                  "()Landroid/view/SurfaceHolder;");
+        if (!holder.isValid()) {
+            m_surfaceView = QJNIObjectPrivate();
+        } else {
+            m_surfaceHolder = new AndroidSurfaceHolder(holder);
+            connect(m_surfaceHolder, &AndroidSurfaceHolder::surfaceCreated,
+                    this, &AndroidSurfaceView::surfaceCreated);
+            { // Lock now to avoid a race with handleSurfaceCreated()
+                QMutexLocker locker(shLock);
+                m_window = QWindow::fromWinId(WId(m_surfaceView.object()));
+
+                if (m_pendingVisible != -1)
+                    m_window->setVisible(m_pendingVisible);
+                if (m_pendingGeometry.isValid())
+                    m_window->setGeometry(m_pendingGeometry);
+            }
+        }
+
+        return true;
+    }
+
+    return QObject::event(e);
+}
+
+// Called on the Android UI thread.
+void AndroidSurfaceView::run()
+{
+    m_surfaceView = QJNIObjectPrivate("android/view/SurfaceView",
+                                      "(Landroid/content/Context;)V",
+                                      QtAndroidPrivate::activity());
+    QCoreApplication::postEvent(this, new QEvent(QEvent::User));
+}
+
+QT_END_NAMESPACE