Android: fix adjusting camera viewfinder resolution.

The viewfinder resolution must be in the same aspect ratio as the
image capture resolution. When adjusting the viewfinder resolution to
comply with that restriction, we assumed that the ratios had to be
exactly equal. Though, in practice, there can be a small difference.
For example for resolutions 2592x1952 (ratio=1.3278) and resolution
640x480 (ratio=1.3333).

Task-number: QTBUG-37525
Change-Id: Ia5a6dd3a4a6d901b24bf74f8aa4e34bffe61f89b
Reviewed-by: Christian Stromme <christian.stromme@theqtcompany.com>

1 files changed, 14 insertions, 9 deletions

diff --git a/src/plugins/android/src/mediacapture/qandroidcamerasession.cpp b/src/plugins/android/src/mediacapture/qandroidcamerasession.cpp
index 5a645bdf5..1ad28e1c8 100644
--- a/src/plugins/android/src/mediacapture/qandroidcamerasession.cpp
+++ b/src/plugins/android/src/mediacapture/qandroidcamerasession.cpp
@@ -276,33 +276,38 @@ void QAndroidCameraSession::adjustViewfinderSize(const QSize &captureSize, bool
     if (!m_camera)
         return;
 
-    QSize viewfinderResolution = m_camera->previewSize();
+    QSize currentViewfinderResolution = m_camera->previewSize();
     const qreal aspectRatio = qreal(captureSize.width()) / qreal(captureSize.height());
-    if (viewfinderResolution.isValid() &&
-            qFuzzyCompare(aspectRatio,
-                          qreal(viewfinderResolution.width()) / viewfinderResolution.height())) {
+    if (currentViewfinderResolution.isValid() &&
+            qAbs(aspectRatio - (qreal(currentViewfinderResolution.width()) / currentViewfinderResolution.height())) < 0.01) {
         return;
     }
 
+    QSize adjustedViewfinderResolution;
     QList<QSize> previewSizes = m_camera->getSupportedPreviewSizes();
     for (int i = previewSizes.count() - 1; i >= 0; --i) {
         const QSize &size = previewSizes.at(i);
         // search for viewfinder resolution with the same aspect ratio
-        if (qFuzzyCompare(aspectRatio, (static_cast<qreal>(size.width())/static_cast<qreal>(size.height())))) {
-            viewfinderResolution = size;
+        if (qAbs(aspectRatio - (qreal(size.width()) / size.height())) < 0.01) {
+            adjustedViewfinderResolution = size;
             break;
         }
     }
 
-    if (m_camera->previewSize() != viewfinderResolution) {
+    if (!adjustedViewfinderResolution.isValid()) {
+        qWarning("Cannot find a viewfinder resolution matching the capture aspect ratio.");
+        return;
+    }
+
+    if (currentViewfinderResolution != adjustedViewfinderResolution) {
         if (m_videoOutput)
-            m_videoOutput->setVideoSize(viewfinderResolution);
+            m_videoOutput->setVideoSize(adjustedViewfinderResolution);
 
         // if preview is started, we have to stop it first before changing its size
         if (m_previewStarted && restartPreview)
             m_camera->stopPreview();
 
-        m_camera->setPreviewSize(viewfinderResolution);
+        m_camera->setPreviewSize(adjustedViewfinderResolution);
 
         // restart preview
         if (m_previewStarted && restartPreview)