Android: fixed image capture preview.

We used to generate the capture preview from the video output, grabbing
the pixels of the last frame (in a FBO). This is not possible anymore,
we instead query the camera for a preview frame, which is in the NV21
format and needs to be converted to RGB.

Change-Id: I1c728b3a708a6f052a83aebf9f15f511eab7a02f
Reviewed-by: Christian Stromme <christian.stromme@digia.com>

5 files changed, 27 insertions, 10 deletions

diff --git a/src/plugins/android/src/common/qandroidmultimediautils.cpp b/src/plugins/android/src/common/qandroidmultimediautils.cpp
index 7ae40358f..9bf38a869 100644
--- a/src/plugins/android/src/common/qandroidmultimediautils.cpp
+++ b/src/plugins/android/src/common/qandroidmultimediautils.cpp
@@ -76,4 +76,29 @@ bool qt_sizeLessThan(const QSize &s1, const QSize &s2)
     return s1.width() * s1.height() < s2.width() * s2.height();
 }
 
+void qt_convert_NV21_to_ARGB32(const uchar *yuv, quint32 *rgb, int width, int height)
+{
+    const int frameSize = width * height;
+
+    int a = 0;
+    for (int i = 0, ci = 0; i < height; ++i, ci += 1) {
+        for (int j = 0, cj = 0; j < width; ++j, cj += 1) {
+            int y = (0xff & ((int) yuv[ci * width + cj]));
+            int v = (0xff & ((int) yuv[frameSize + (ci >> 1) * width + (cj & ~1) + 0]));
+            int u = (0xff & ((int) yuv[frameSize + (ci >> 1) * width + (cj & ~1) + 1]));
+            y = y < 16 ? 16 : y;
+
+            int r = (int) (1.164f * (y - 16) + 1.596f * (v - 128));
+            int g = (int) (1.164f * (y - 16) - 0.813f * (v - 128) - 0.391f * (u - 128));
+            int b = (int) (1.164f * (y - 16) + 2.018f * (u - 128));
+
+            r = qBound(0, r, 255);
+            g = qBound(0, g, 255);
+            b = qBound(0, b, 255);
+
+            rgb[a++] = 0xff000000 | (r << 16) | (g << 8) | b;
+        }
+    }
+}
+
 QT_END_NAMESPACE
diff --git a/src/plugins/android/src/common/qandroidmultimediautils.h b/src/plugins/android/src/common/qandroidmultimediautils.h
index 1996209b0..792ab06db 100644
--- a/src/plugins/android/src/common/qandroidmultimediautils.h
+++ b/src/plugins/android/src/common/qandroidmultimediautils.h
@@ -53,6 +53,8 @@ int qt_findClosestValue(const QList<int> &list, int value);
 
 bool qt_sizeLessThan(const QSize &s1, const QSize &s2);
 
+void qt_convert_NV21_to_ARGB32(const uchar *yuv, quint32 *rgb, int width, int height);
+
 QT_END_NAMESPACE
 
 #endif // QANDROIDMULTIMEDIAUTILS_H
diff --git a/src/plugins/android/src/common/qandroidvideooutput.h b/src/plugins/android/src/common/qandroidvideooutput.h
index 1ad64a4b4..6e4a32e3f 100644
--- a/src/plugins/android/src/common/qandroidvideooutput.h
+++ b/src/plugins/android/src/common/qandroidvideooutput.h
@@ -61,8 +61,6 @@ public:
     virtual void setVideoSize(const QSize &) { }
     virtual void stop() { }
 
-    virtual QImage toImage() = 0;
-
     // signals:
     // void readyChanged(bool);
 };
diff --git a/src/plugins/android/src/common/qandroidvideorendercontrol.cpp b/src/plugins/android/src/common/qandroidvideorendercontrol.cpp
index b9aac6434..5306fe918 100644
--- a/src/plugins/android/src/common/qandroidvideorendercontrol.cpp
+++ b/src/plugins/android/src/common/qandroidvideorendercontrol.cpp
@@ -223,13 +223,6 @@ void QAndroidVideoRendererControl::stop()
     m_nativeSize = QSize();
 }
 
-QImage QAndroidVideoRendererControl::toImage()
-{
-    // FIXME!!! Since we are not using a FBO anymore, we can't grab the pixels. And glGetTexImage
-    // doesn't work on GL_TEXTURE_EXTERNAL_OES
-    return QImage();
-}
-
 void QAndroidVideoRendererControl::onFrameAvailable()
 {
     if (!m_nativeSize.isValid() || !m_surface)
diff --git a/src/plugins/android/src/common/qandroidvideorendercontrol.h b/src/plugins/android/src/common/qandroidvideorendercontrol.h
index e98495ede..5d9130c07 100644
--- a/src/plugins/android/src/common/qandroidvideorendercontrol.h
+++ b/src/plugins/android/src/common/qandroidvideorendercontrol.h
@@ -77,7 +77,6 @@ public:
     bool isReady() Q_DECL_OVERRIDE;
     void setVideoSize(const QSize &size) Q_DECL_OVERRIDE;
     void stop() Q_DECL_OVERRIDE;
-    QImage toImage() Q_DECL_OVERRIDE;
 
     void customEvent(QEvent *) Q_DECL_OVERRIDE;