DirectShow: Implement image capture settings

Added camera image encoder control that
1. applies image encoder settings (resolution and codec) used to capture images
2. returns supported image codecs from
QImageWriter::supportedImageFormats
3. returns supported resolutions

Since DirectShow camera session uses QImage based on QVideoFrame
image encoder control returns viewfinder supported resolutions.
Not available if camera is not loaded.

Setting resolution via encoder control causes viewfinder resolution to be ignored.

Task-number: QTBUG-32743
Change-Id: I1de3ca9c6543937cb62f73cb64a81d23b0d5c4c9
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
Reviewed-by: Andy Shaw <andy.shaw@qt.io>
Reviewed-by: Christian Stromme <christian.stromme@qt.io>

1 files changed, 95 insertions, 0 deletions

diff --git a/src/plugins/directshow/camera/directshowcameraimageencodercontrol.cpp b/src/plugins/directshow/camera/directshowcameraimageencodercontrol.cpp
new file mode 100644
index 000000000..912f67a2d
--- /dev/null
+++ b/src/plugins/directshow/camera/directshowcameraimageencodercontrol.cpp
@@ -0,0 +1,95 @@
+/****************************************************************************
+**
+** 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 "directshowcameraimageencodercontrol.h"
+#include "dscamerasession.h"
+#include <QImageWriter>
+
+QT_BEGIN_NAMESPACE
+
+DirectShowCameraImageEncoderControl::DirectShowCameraImageEncoderControl(DSCameraSession *session)
+    : QImageEncoderControl(session)
+    , m_session(session)
+{
+}
+
+QList<QSize> DirectShowCameraImageEncoderControl::supportedResolutions(const QImageEncoderSettings &settings, bool *continuous) const
+{
+    QList<QSize> res;
+    if (!settings.codec().isEmpty() && !supportedImageCodecs().contains(settings.codec(), Qt::CaseInsensitive))
+        return res;
+
+    QList<QSize> resolutions = m_session->supportedResolutions(continuous);
+    QSize r = settings.resolution();
+    if (!r.isValid())
+        return resolutions;
+
+    if (resolutions.contains(r))
+        res << settings.resolution();
+
+    return res;
+}
+
+QStringList DirectShowCameraImageEncoderControl::supportedImageCodecs() const
+{
+    QStringList supportedCodecs;
+    for (const QByteArray &type: QImageWriter::supportedImageFormats()) {
+        supportedCodecs << type;
+    }
+
+    return supportedCodecs;
+}
+
+QString DirectShowCameraImageEncoderControl::imageCodecDescription(const QString &codecName) const
+{
+    Q_UNUSED(codecName);
+    return QString();
+}
+
+QImageEncoderSettings DirectShowCameraImageEncoderControl::imageSettings() const
+{
+    return m_session->imageEncoderSettings();
+}
+
+void DirectShowCameraImageEncoderControl::setImageSettings(const QImageEncoderSettings &settings)
+{
+    m_session->setImageEncoderSettings(settings);
+}
+
+QT_END_NAMESPACE