diff --git a/inc/leptonvariation.h b/inc/leptonvariation.h
index 126f83c..38c0ffb 100644
--- a/inc/leptonvariation.h
+++ b/inc/leptonvariation.h
@@ -96,12 +96,13 @@ class LeptonVariation : public AbstractCCInterface
     Q_PROPERTY(unsigned int radSpotmeterInKelvinX100 READ getRadSpotmeterObjInKelvinX100 NOTIFY radSpotmeterInKelvinX100Changed)
     unsigned int getRadSpotmeterObjInKelvinX100();
 
-    Q_PROPERTY(const QRect& radSpotmeterRoi READ getRadSpotmeterRoi NOTIFY radSpotmeterRoiChanged)
+    Q_PROPERTY(const QRect& radSpotmeterRoi READ getRadSpotmeterRoi WRITE setRadSpotmeterRoi NOTIFY radSpotmeterRoiChanged)
     const QRect getRadSpotmeterRoi() {
         return QRect(m_spotmeterRoi.startCol, m_spotmeterRoi.startRow,
                      m_spotmeterRoi.endCol - m_spotmeterRoi.startCol,
                      m_spotmeterRoi.endRow - m_spotmeterRoi.startRow);
     }
+    void setRadSpotmeterRoi(const QRect& roi);
 
     SDK_ENUM_PROPERTY(RAD_TLINEAR_RESOLUTION_E, radTLinearResolution, RadTLinearResolution)
 
diff --git a/qml/ViewerForm.ui.qml b/qml/ViewerForm.ui.qml
index aae9c7d..dd014d9 100644
--- a/qml/ViewerForm.ui.qml
+++ b/qml/ViewerForm.ui.qml
@@ -54,7 +54,6 @@ Item {
                     acq: acq
                     anchors.horizontalCenter: parent.horizontalCenter
                     anchors.verticalCenter: parent.verticalCenter
-                    roi: acq.cci.radSpotmeterRoi
                 }
             }
         }
diff --git a/qml/controls/VideoRoi.qml b/qml/controls/VideoRoi.qml
index 8a948e5..8e02992 100644
--- a/qml/controls/VideoRoi.qml
+++ b/qml/controls/VideoRoi.qml
@@ -5,18 +5,58 @@ import GetThermal 1.0
 Item {
     id: root
 
-    width: parent.width
-    height: (parent.width * acq.videoSize.height) / acq.videoSize.width
+    anchors.fill: parent
 
     property UvcAcquisition acq: null
-    property var roi: null
-
-    Rectangle {
-        x: (roi.x * parent.width) / acq.videoSize.width
-        y: (roi.y * parent.height) / acq.videoSize.height
-        width: (roi.width * parent.width) / acq.videoSize.width
-        height: (roi.height * parent.height) / acq.videoSize.height
-        color: "#80ffffff"
-        border.color: "#80000000"
+    property rect roi: acq && acq.cci ? acq.cci.radSpotmeterRoi : Qt.rect(0, 0, 80, 60)
+    property size videoSize: acq ? acq.videoSize : Qt.size(80, 60)
+
+    function moveUnscaledRoiTo(dispX, dispY) {
+        var nx = Math.floor(dispX * (videoSize.width / scaledvid.width))
+        var ny = Math.floor(dispY * (videoSize.height / scaledvid.height))
+        if (roi.x === nx && roi.y === ny) {
+            return
+        }
+        acq.cci.radSpotmeterRoi = Qt.rect(nx, ny, roi.width, roi.height)
+    }
+
+    Item {
+        id: scaledvid
+
+        width: root.width
+        height: (root.width * videoSize.height) / videoSize.width
+        anchors.centerIn: root
+
+        MouseArea {
+            cursorShape: Qt.CrossCursor
+            anchors.fill: parent
+            onClicked: {
+                moveUnscaledRoiTo(mouse.x, mouse.y)
+            }
+        }
+
+        Rectangle {
+            id: roidisp
+
+            x: roi.x * (scaledvid.width / videoSize.width)
+            y: roi.y * (scaledvid.height / videoSize.height)
+            width: roi.width * (scaledvid.width / videoSize.width)
+            height: roi.height * (scaledvid.height / videoSize.height)
+
+            color: "#80ffffff"
+            border.color: "#80000000"
+
+            MouseArea {
+                cursorShape: drag.active ? Qt.ClosedHandCursor : Qt.OpenHandCursor
+                anchors.fill: parent
+                drag.target: roidisp
+                drag.axis: Drag.XAndYAxis
+                drag.smoothed: false
+                drag.threshold: 1
+                onPositionChanged: {
+                    moveUnscaledRoiTo(roidisp.x, roidisp.y)
+                }
+            }
+        }
     }
 }
diff --git a/src/leptonvariation.cpp b/src/leptonvariation.cpp
index 33a48c8..65a3e81 100644
--- a/src/leptonvariation.cpp
+++ b/src/leptonvariation.cpp
@@ -173,6 +173,24 @@ unsigned int LeptonVariation::getRadSpotmeterObjInKelvinX100()
         return 0;
 }
 
+void LeptonVariation::setRadSpotmeterRoi(const QRect& roi)
+{
+    LEP_RAD_ROI_T newSpot = {
+        static_cast<unsigned short>(roi.y()),
+        static_cast<unsigned short>(roi.x()),
+        static_cast<unsigned short>(roi.y() + roi.height()),
+        static_cast<unsigned short>(roi.x() + roi.width())
+    };
+
+    if (LEP_SetRadSpotmeterRoi(&m_portDesc, newSpot) != LEP_OK) {
+        printf("LEP_SetRadSpotmeterRoi failed");
+        return;
+    }
+
+    m_spotmeterRoi = newSpot;
+    emit radSpotmeterRoiChanged();
+    emit radSpotmeterInKelvinX100Changed();
+}
 
 void LeptonVariation::performFfc()
 {