Clean up zooming API

There is very little point these days in having properties
for both optical and digital zoom. Most mobile cameras don't
have a real optical zoom, but instead combine different cameras
with different focal lengths.

Change-Id: Icac48d949e767d7f3105c4d330e15273fe715fbe
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
Reviewed-by: Doris Verria <doris.verria@qt.io>

9 files changed, 77 insertions, 211 deletions

diff --git a/src/multimedia/camera/qcamerafocus.cpp b/src/multimedia/camera/qcamerafocus.cpp
index 0f8f8eaa0..7fa30a859 100644
--- a/src/multimedia/camera/qcamerafocus.cpp
+++ b/src/multimedia/camera/qcamerafocus.cpp
@@ -50,14 +50,6 @@
 
 QT_BEGIN_NAMESPACE
 
-static void qRegisterCameraFocusMetaTypes()
-{
-    qRegisterMetaType<QCameraFocus::FocusModes>("QCameraFocus::FocusModes");
-    qRegisterMetaType<QCameraFocus::FocusPointMode>("QCameraFocus::FocusPointMode");
-}
-
-Q_CONSTRUCTOR_FUNCTION(qRegisterCameraFocusMetaTypes)
-
 class QCameraFocusFakeFocusControl : public QCameraFocusControl
 {
 public:
@@ -76,15 +68,11 @@ public:
 
     [[nodiscard]] QCameraFocusZoneList focusZones() const override { return QCameraFocusZoneList(); }
 
-    [[nodiscard]] qreal maximumOpticalZoom() const override { return 1.0; }
-    [[nodiscard]] qreal maximumDigitalZoom() const override { return 1.0; }
-
-    [[nodiscard]] qreal requestedOpticalZoom() const override { return 1.0; }
-    [[nodiscard]] qreal requestedDigitalZoom() const override { return 1.0; }
-    [[nodiscard]] qreal currentOpticalZoom() const override { return 1.0; }
-    [[nodiscard]] qreal currentDigitalZoom() const override { return 1.0; }
-
-    void zoomTo(qreal, qreal) override { qWarning("The camera doesn't support zooming."); }
+    ZoomRange zoomFactorRange() const override { return {1., 1.}; };
+    void zoomTo(float, float) override
+    {
+        qWarning("The camera doesn't support zooming.");
+    }
 };
 
 
@@ -297,6 +285,7 @@ public:
 
     QCameraFocusControl *focusControl;
     bool available;
+    float zoomFactor = 1.;
 };
 
 
@@ -454,61 +443,54 @@ QCameraFocusZoneList QCameraFocus::focusZones() const
 }
 
 /*!
-    Returns the maximum optical zoom.
+    Returns the maximum zoom factor.
 
-    This will be \c 1.0 on cameras that do not support optical zoom.
+    This will be \c 1.0 on cameras that do not support zooming.
 */
 
-qreal QCameraFocus::maximumOpticalZoom() const
+float QCameraFocus::maximumZoomFactor() const
 {
-    return d_func()->focusControl->maximumOpticalZoom();
+    return d_func()->focusControl->zoomFactorRange().max;
 }
 
 /*!
-    Returns the maximum digital zoom
+    Returns the minimum zoom factor.
 
-    This will be \c 1.0 on cameras that do not support digital zoom.
+    This will be \c 1.0 on cameras that do not support zooming.
 */
 
-qreal QCameraFocus::maximumDigitalZoom() const
+float QCameraFocus::minimumZoomFactor() const
 {
-    return d_func()->focusControl->maximumDigitalZoom();
+    return d_func()->focusControl->zoomFactorRange().min;
 }
 
 /*!
-  \property QCameraFocus::opticalZoom
-  \brief the current optical zoom value.
-
-  \sa QCameraFocus::digitalZoom
+  \property QCameraFocus::zoomFactor
+  \brief The current zoom factor.
 */
-
-qreal QCameraFocus::opticalZoom() const
+float QCameraFocus::zoomFactor() const
 {
-    return d_func()->focusControl->currentOpticalZoom();
+    return d_func()->zoomFactor;
 }
 
-/*!
-  \property QCameraFocus::digitalZoom
-  \brief the current digital zoom value.
-
-  \sa QCameraFocus::opticalZoom
-*/
-qreal QCameraFocus::digitalZoom() const
+void QCameraFocus::setZoomFactor(float factor)
 {
-    return d_func()->focusControl->currentDigitalZoom();
+    Q_D(QCameraFocus);
+    d->zoomFactor = factor;
+    d->focusControl->zoomTo(factor, -1);
 }
 
-
 /*!
-    Set the camera \a optical and \a digital zoom values.
+    Zooms to a zoom factor \a factor using \a rate.
 
-    Since there may be a physical component to move, the change in
-    zoom value may not be instantaneous.
-
-*/
-void QCameraFocus::zoomTo(qreal optical, qreal digital)
+    The rate is specified in powers of two per second. A rate of 1
+    would take two seconds to zoom from a zoom factor of 1 to a zoom factor of 4.
+ */
+void QCameraFocus::zoomTo(float factor, float rate)
 {
-    d_func()->focusControl->zoomTo(optical, digital);
+    Q_D(QCameraFocus);
+    d->zoomFactor = factor;
+    d->focusControl->zoomTo(factor, rate);
 }
 
 /*!
diff --git a/src/multimedia/camera/qcamerafocus.h b/src/multimedia/camera/qcamerafocus.h
index c8f7ae60d..1b8d69628 100644
--- a/src/multimedia/camera/qcamerafocus.h
+++ b/src/multimedia/camera/qcamerafocus.h
@@ -99,8 +99,7 @@ class Q_MULTIMEDIA_EXPORT QCameraFocus : public QObject
     Q_PROPERTY(FocusPointMode focusPointMode READ focusPointMode WRITE setFocusPointMode)
     Q_PROPERTY(QPointF customFocusPoint READ customFocusPoint WRITE setCustomFocusPoint)
     Q_PROPERTY(QCameraFocusZoneList focusZones READ focusZones NOTIFY focusZonesChanged)
-    Q_PROPERTY(qreal opticalZoom READ opticalZoom NOTIFY opticalZoomChanged)
-    Q_PROPERTY(qreal digitalZoom READ digitalZoom NOTIFY digitalZoomChanged)
+    Q_PROPERTY(float zoomFactor READ zoomFactor WRITE setZoomFactor NOTIFY zoomFactorChanged)
 
     Q_ENUMS(FocusMode)
     Q_ENUMS(FocusPointMode)
@@ -136,22 +135,17 @@ public:
 
     QCameraFocusZoneList focusZones() const;
 
-    qreal maximumOpticalZoom() const;
-    qreal maximumDigitalZoom() const;
-    qreal opticalZoom() const;
-    qreal digitalZoom() const;
+    float minimumZoomFactor() const;
+    float maximumZoomFactor() const;
+    float zoomFactor() const;
+    void setZoomFactor(float factor);
 
-    void zoomTo(qreal opticalZoom, qreal digitalZoom);
+    void zoomTo(float zoom, float rate);
 
 Q_SIGNALS:
-    void opticalZoomChanged(qreal);
-    void digitalZoomChanged(qreal);
-
+    void zoomFactorChanged(float);
     void focusZonesChanged();
 
-    void maximumOpticalZoomChanged(qreal);
-    void maximumDigitalZoomChanged(qreal);
-
 protected:
     ~QCameraFocus();
 
diff --git a/src/multimedia/controls/qcamerafocuscontrol.h b/src/multimedia/controls/qcamerafocuscontrol.h
index 871f240da..cf5c391bd 100644
--- a/src/multimedia/controls/qcamerafocuscontrol.h
+++ b/src/multimedia/controls/qcamerafocuscontrol.h
@@ -67,15 +67,14 @@ public:
 
     virtual QCameraFocusZoneList focusZones() const = 0;
 
-    virtual qreal maximumOpticalZoom() const = 0;
-    virtual qreal maximumDigitalZoom() const = 0;
+    struct ZoomRange {
+        float min;
+        float max;
+    };
 
-    virtual qreal requestedOpticalZoom() const = 0;
-    virtual qreal requestedDigitalZoom() const = 0;
-    virtual qreal currentOpticalZoom() const = 0;
-    virtual qreal currentDigitalZoom() const = 0;
-
-    virtual void zoomTo(qreal optical, qreal digital) = 0;
+    virtual ZoomRange zoomFactorRange() const = 0;
+    // smaller 0: zoom instantly, rate in power-of-two/sec
+    virtual void zoomTo(float newZoomFactor, float rate = -1.) = 0;
 
 Q_SIGNALS:
     void focusModeChanged(QCameraFocus::FocusModes mode);
@@ -84,13 +83,6 @@ Q_SIGNALS:
 
     void focusZonesChanged();
 
-    void maximumOpticalZoomChanged(qreal);
-    void maximumDigitalZoomChanged(qreal);
-
-    void requestedOpticalZoomChanged(qreal opticalZoom);
-    void requestedDigitalZoomChanged(qreal digitalZoom);
-    void currentOpticalZoomChanged(qreal opticalZoom);
-    void currentDigitalZoomChanged(qreal digitalZoom);
 
 protected:
     explicit QCameraFocusControl(QObject *parent = nullptr);
diff --git a/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol.cpp b/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol.cpp
index 0fa9b055a..b1805ff15 100644
--- a/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol.cpp
+++ b/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol.cpp
@@ -234,15 +234,11 @@ void QAndroidCameraFocusControl::onCameraOpened()
         qreal maxZoom = m_zoomRatios.last() / qreal(100);
         if (m_maximumZoom != maxZoom) {
             m_maximumZoom = maxZoom;
-            emit maximumDigitalZoomChanged(m_maximumZoom);
         }
-        zoomTo(1, m_requestedZoom);
+        zoomTo(1, -1);
     } else {
         m_zoomRatios.clear();
-        if (!qFuzzyCompare(m_maximumZoom, qreal(1))) {
-            m_maximumZoom = 1.0;
-            emit maximumDigitalZoomChanged(m_maximumZoom);
-        }
+        m_maximumZoom = 1.0;
     }
 }
 
@@ -326,56 +322,26 @@ void QAndroidCameraFocusControl::onAutoFocusComplete(bool success)
 }
 
 
-qreal QAndroidCameraFocusControl::maximumOpticalZoom() const
-{
-    // Optical zoom not supported
-    return 1.0;
-}
-
-qreal QAndroidCameraFocusControl::maximumDigitalZoom() const
-{
-    return m_maximumZoom;
-}
-
-qreal QAndroidCameraFocusControl::requestedOpticalZoom() const
-{
-    // Optical zoom not supported
-    return 1.0;
-}
-
-qreal QAndroidCameraFocusControl::requestedDigitalZoom() const
-{
-    return m_requestedZoom;
-}
-
-qreal QAndroidCameraFocusControl::currentOpticalZoom() const
-{
-    // Optical zoom not supported
-    return 1.0;
-}
-
-qreal QAndroidCameraFocusControl::currentDigitalZoom() const
+QAndroidCameraFocusControl::ZoomRange QAndroidCameraFocusControl::zoomFactorRange() const
 {
-    return m_currentZoom;
+    return { 1., m_maximumZoom };
 }
 
-void QAndroidCameraFocusControl::zoomTo(qreal optical, qreal digital)
+void QAndroidCameraFocusControl::zoomTo(float factor, float rate)
 {
-    Q_UNUSED(optical);
+    Q_UNUSED(rate);
 
-    if (!qFuzzyCompare(m_requestedZoom, digital)) {
-        m_requestedZoom = digital;
-        emit requestedDigitalZoomChanged(m_requestedZoom);
+    if (!qFuzzyCompare(m_requestedZoom, factor)) {
+        m_requestedZoom = factor;
     }
 
     if (m_session->camera()) {
-        digital = qBound(qreal(1), digital, m_maximumZoom);
-        int validZoomIndex = qt_findClosestValue(m_zoomRatios, qRound(digital * 100));
-        qreal newZoom = m_zoomRatios.at(validZoomIndex) / qreal(100);
+        factor = qBound(qreal(1), factor, m_maximumZoom);
+        int validZoomIndex = qt_findClosestValue(m_zoomRatios, qRound(factor * 100));
+        float newZoom = m_zoomRatios.at(validZoomIndex) / qreal(100);
         if (!qFuzzyCompare(m_currentZoom, newZoom)) {
             m_session->camera()->setZoom(validZoomIndex);
             m_currentZoom = newZoom;
-            emit currentDigitalZoomChanged(m_currentZoom);
         }
     }
 }
diff --git a/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol_p.h b/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol_p.h
index cf9c73017..79ab30f4f 100644
--- a/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol_p.h
+++ b/src/multimedia/platform/android/mediacapture/qandroidcamerafocuscontrol_p.h
@@ -73,13 +73,8 @@ public:
     void setCustomFocusPoint(const QPointF &point) override;
     QCameraFocusZoneList focusZones() const override;
 
-    qreal maximumOpticalZoom() const override;
-    qreal maximumDigitalZoom() const override;
-    qreal requestedOpticalZoom() const override;
-    qreal requestedDigitalZoom() const override;
-    qreal currentOpticalZoom() const override;
-    qreal currentDigitalZoom() const override;
-    void zoomTo(qreal optical, qreal digital) override;
+    ZoomRange zoomFactorRange() const override;
+    void zoomTo(float newZoomFactor, float rate) override;
 
 private Q_SLOTS:
     void onCameraOpened();
@@ -122,10 +117,10 @@ private:
 
     QList<QCameraFocus::FocusPointMode> m_supportedFocusPointModes;
 
-    qreal m_maximumZoom;
+    float m_maximumZoom;
     QList<int> m_zoomRatios;
-    qreal m_requestedZoom;
-    qreal m_currentZoom;
+    float m_requestedZoom;
+    float m_currentZoom;
 };
 
 QT_END_NAMESPACE
diff --git a/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol.mm b/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol.mm
index 62a7d55e2..ea9827324 100644
--- a/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol.mm
+++ b/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol.mm
@@ -327,80 +327,32 @@ void AVFCameraFocusControl::cameraStateChanged()
         Q_EMIT maximumDigitalZoomChanged(1.);
     }
 
-    zoomToRequestedDigital();
+    captureDevice.videoZoomFactor = m_zoomFactor;
 #endif
 }
 
-qreal AVFCameraFocusControl::maximumOpticalZoom() const
+AVFCameraFocusControl::ZoomRange AVFCameraFocusControl::zoomFactorRange() const
 {
-    // Not supported.
-    return 1.;
+    return { 1., (float)m_maxZoomFactor };
 }
 
-qreal AVFCameraFocusControl::maximumDigitalZoom() const
+void AVFCameraFocusControl::zoomTo(float factor, float rate)
 {
-    return m_maxZoomFactor;
-}
-
-qreal AVFCameraFocusControl::requestedOpticalZoom() const
-{
-    // Not supported.
-    return 1;
-}
-
-qreal AVFCameraFocusControl::requestedDigitalZoom() const
-{
-    return m_requestedZoomFactor;
-}
-
-qreal AVFCameraFocusControl::currentOpticalZoom() const
-{
-    // Not supported.
-    return 1.;
-}
-
-qreal AVFCameraFocusControl::currentDigitalZoom() const
-{
-    return m_zoomFactor;
-}
-
-void AVFCameraFocusControl::zoomTo(qreal optical, qreal digital)
-{
-    Q_UNUSED(optical);
-    Q_UNUSED(digital);
+    Q_UNUSED(factor);
+    Q_UNUSED(rate);
 
 #ifdef QOS_IOS
-    if (qFuzzyCompare(CGFloat(digital), m_requestedZoomFactor))
+    if (qFuzzyCompare(CGFloat(factor), m_zoomFactor))
         return;
 
-    m_requestedZoomFactor = digital;
+    m_requestedZoomFactor = factor;
     Q_EMIT requestedDigitalZoomChanged(digital);
 
-    zoomToRequestedDigital();
-#endif
-}
-
-#ifdef QOS_IOS
-void AVFCameraFocusControl::zoomToRequestedDigital()
-{
     AVCaptureDevice *captureDevice = m_session->videoCaptureDevice();
     if (!captureDevice || !captureDevice.activeFormat)
         return;
 
-    if (qFuzzyCompare(captureDevice.activeFormat.videoMaxZoomFactor, CGFloat(1.)))
-        return;
-
-    const CGFloat clampedZoom = qBound(CGFloat(1.), m_requestedZoomFactor,
-                                       captureDevice.activeFormat.videoMaxZoomFactor);
-    const CGFloat deviceZoom = captureDevice.videoZoomFactor;
-    if (qFuzzyCompare(clampedZoom, deviceZoom)) {
-        // Nothing to set, but check if a signal must be emitted:
-        if (!qFuzzyCompare(m_zoomFactor, deviceZoom)) {
-            m_zoomFactor = deviceZoom;
-            Q_EMIT currentDigitalZoomChanged(deviceZoom);
-        }
-        return;
-    }
+    m_zoomFactor = qBound(CGFloat(1.), factor, captureDevice.activeFormat.videoMaxZoomFactor);
 
     const AVFConfigurationLock lock(captureDevice);
     if (!lock) {
@@ -408,14 +360,12 @@ void AVFCameraFocusControl::zoomToRequestedDigital()
         return;
     }
 
-    captureDevice.videoZoomFactor = clampedZoom;
-
-    if (!qFuzzyCompare(clampedZoom, m_zoomFactor)) {
-        m_zoomFactor = clampedZoom;
-        Q_EMIT currentDigitalZoomChanged(clampedZoom);
-    }
-}
+    if (rate < 0)
+        captureDevice.videoZoomFactor = clampedZoom;
+    else
+        [AVCaptureDevice rampToVideoZoomFactor:factor withRate:rate];
 #endif
+}
 
 QT_END_NAMESPACE
 
diff --git a/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol_p.h b/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol_p.h
index 3527d48b6..e1f8d9aec 100644
--- a/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol_p.h
+++ b/src/multimedia/platform/darwin/camera/avfcamerafocuscontrol_p.h
@@ -83,24 +83,13 @@ public:
 
     QCameraFocusZoneList focusZones() const override;
 
-    qreal maximumOpticalZoom() const override;
-    qreal maximumDigitalZoom() const override;
-
-    qreal requestedOpticalZoom() const override;
-    qreal requestedDigitalZoom() const override;
-    qreal currentOpticalZoom() const override;
-    qreal currentDigitalZoom() const override;
-
-    void zoomTo(qreal optical, qreal digital) override;
+    ZoomRange zoomFactorRange() const override;
+    void zoomTo(float newZoomFactor, float rate = -1.) override;
 
 private Q_SLOTS:
     void cameraStateChanged();
 
 private:
-#ifdef QOS_IOS
-    void zoomToRequestedDigital();
-#endif
-
     AVFCameraSession *m_session;
     QCameraFocus::FocusModes m_focusMode;
     QCameraFocus::FocusPointMode m_focusPointMode;
@@ -109,7 +98,6 @@ private:
 
     CGFloat m_maxZoomFactor;
     CGFloat m_zoomFactor;
-    CGFloat m_requestedZoomFactor;
 };
 
 
diff --git a/src/multimedia/platform/gstreamer/mediacapture/qgstreamervideoinput.cpp b/src/multimedia/platform/gstreamer/mediacapture/qgstreamervideoinput.cpp
index fedca45fc..0f87339df 100644
--- a/src/multimedia/platform/gstreamer/mediacapture/qgstreamervideoinput.cpp
+++ b/src/multimedia/platform/gstreamer/mediacapture/qgstreamervideoinput.cpp
@@ -44,7 +44,7 @@
 
 #include <private/qgstreamerintegration_p.h>
 #include <private/qgstreamerdevicemanager_p.h>
-
+#include <private/qgstutils_p.h>
 #include <algorithm>
 
 QGstreamerVideoInput::QGstreamerVideoInput()
diff --git a/src/multimedia/platform/gstreamer/qgstreamerdevicemanager.cpp b/src/multimedia/platform/gstreamer/qgstreamerdevicemanager.cpp
index b81ef86a3..3706ed278 100644
--- a/src/multimedia/platform/gstreamer/qgstreamerdevicemanager.cpp
+++ b/src/multimedia/platform/gstreamer/qgstreamerdevicemanager.cpp
@@ -140,7 +140,6 @@ QList<QCameraInfo> QGstreamerDeviceManager::videoInputs() const
 
     for (auto *d : qAsConst(m_videoSources)) {
         QGstStructure properties = gst_device_get_properties(d);
-        qDebug() << properties.toString();
         if (!properties.isNull()) {
             QCameraInfoPrivate *info = new QCameraInfoPrivate;
             auto *desc = gst_device_get_display_name(d);