2 files changed, 52 insertions, 30 deletions

diff --git a/src/plugins/directshow/camera/dsvideodevicecontrol.cpp b/src/plugins/directshow/camera/dsvideodevicecontrol.cpp
index 869299457..c3d23e027 100644
--- a/src/plugins/directshow/camera/dsvideodevicecontrol.cpp
+++ b/src/plugins/directshow/camera/dsvideodevicecontrol.cpp
@@ -33,6 +33,7 @@
 
 #include <QDebug>
 #include <QFile>
+#include <qelapsedtimer.h>
 
 #include "dsvideodevicecontrol.h"
 #include "dscamerasession.h"
@@ -48,33 +49,37 @@ extern const CLSID CLSID_VideoInputDeviceCategory;
 
 QT_BEGIN_NAMESPACE
 
+Q_GLOBAL_STATIC(QList<DSVideoDeviceInfo>, deviceList)
+
 DSVideoDeviceControl::DSVideoDeviceControl(QObject *parent)
     : QVideoDeviceSelectorControl(parent)
 {
     m_session = qobject_cast<DSCameraSession*>(parent);
-
-    enumerateDevices(&m_devices, &m_descriptions);
-
     selected = 0;
 }
 
 int DSVideoDeviceControl::deviceCount() const
 {
-    return m_devices.count();
+    updateDevices();
+    return deviceList->count();
 }
 
 QString DSVideoDeviceControl::deviceName(int index) const
 {
-    if (index >= 0 && index <= m_devices.count())
-        return QString::fromUtf8(m_devices.at(index).constData());
+    updateDevices();
+
+    if (index >= 0 && index <= deviceList->count())
+        return QString::fromUtf8(deviceList->at(index).first.constData());
 
     return QString();
 }
 
 QString DSVideoDeviceControl::deviceDescription(int index) const
 {
-    if (index >= 0 && index <= m_descriptions.count())
-        return m_descriptions.at(index);
+    updateDevices();
+
+    if (index >= 0 && index <= deviceList->count())
+        return deviceList->at(index).second;
 
     return QString();
 }
@@ -89,10 +94,34 @@ int DSVideoDeviceControl::selectedDevice() const
     return selected;
 }
 
-void DSVideoDeviceControl::enumerateDevices(QList<QByteArray> *devices, QStringList *descriptions)
+void DSVideoDeviceControl::setSelectedDevice(int index)
 {
-    devices->clear();
-    descriptions->clear();
+    updateDevices();
+
+    if (index >= 0 && index < deviceList->count()) {
+        if (m_session) {
+            QString device = deviceList->at(index).first;
+            if (device.startsWith("ds:"))
+                device.remove(0,3);
+            m_session->setDevice(device);
+        }
+        selected = index;
+    }
+}
+
+const QList<DSVideoDeviceInfo> &DSVideoDeviceControl::availableDevices()
+{
+    updateDevices();
+    return *deviceList;
+}
+
+void DSVideoDeviceControl::updateDevices()
+{
+    static QElapsedTimer timer;
+    if (timer.isValid() && timer.elapsed() < 500) // ms
+        return;
+
+    deviceList->clear();
 
     ICreateDevEnum* pDevEnum = NULL;
     IEnumMoniker* pEnum = NULL;
@@ -116,7 +145,9 @@ void DSVideoDeviceControl::enumerateDevices(QList<QByteArray> *devices, QStringL
                 if (SUCCEEDED(hr)) {
                     QString output(QString::fromWCharArray(strName));
                     mallocInterface->Free(strName);
-                    devices->append(output.toUtf8().constData());
+
+                    DSVideoDeviceInfo devInfo;
+                    devInfo.first = output.toUtf8();
 
                     IPropertyBag *pPropBag;
                     hr = pMoniker->BindToStorage(0, 0, IID_IPropertyBag, (void**)(&pPropBag));
@@ -130,7 +161,9 @@ void DSVideoDeviceControl::enumerateDevices(QList<QByteArray> *devices, QStringL
                         }
                         pPropBag->Release();
                     }
-                    descriptions->append(output);
+                    devInfo.second = output;
+
+                    deviceList->append(devInfo);
                 }
                 pMoniker->Release();
             }
@@ -139,19 +172,8 @@ void DSVideoDeviceControl::enumerateDevices(QList<QByteArray> *devices, QStringL
         }
         pDevEnum->Release();
     }
-}
 
-void DSVideoDeviceControl::setSelectedDevice(int index)
-{
-    if (index >= 0 && index < m_devices.count()) {
-        if (m_session) {
-            QString device = m_devices.at(index);
-            if (device.startsWith("ds:"))
-                device.remove(0,3);
-            m_session->setDevice(device);
-        }
-        selected = index;
-    }
+    timer.restart();
 }
 
 QT_END_NAMESPACE
diff --git a/src/plugins/directshow/camera/dsvideodevicecontrol.h b/src/plugins/directshow/camera/dsvideodevicecontrol.h
index a6d471088..0ba7ce36a 100644
--- a/src/plugins/directshow/camera/dsvideodevicecontrol.h
+++ b/src/plugins/directshow/camera/dsvideodevicecontrol.h
@@ -42,6 +42,8 @@ class DSCameraSession;
 
 //QTM_USE_NAMESPACE
 
+typedef QPair<QByteArray, QString> DSVideoDeviceInfo;
+
 class DSVideoDeviceControl : public QVideoDeviceSelectorControl
 {
     Q_OBJECT
@@ -54,17 +56,15 @@ public:
     int defaultDevice() const;
     int selectedDevice() const;
 
-    static void enumerateDevices(QList<QByteArray> *devices, QStringList *descriptions);
+    static const QList<DSVideoDeviceInfo> &availableDevices();
 
 public Q_SLOTS:
     void setSelectedDevice(int index);
 
 private:
-    DSCameraSession* m_session;
-
-    QList<QByteArray> m_devices;
-    QStringList m_descriptions;
+    static void updateDevices();
 
+    DSCameraSession* m_session;
     int selected;
 };