Detect device orientation when initalizing iOS capture device

src/videofilters/ioscapture.m

@@ -34,6 +34,9 @@
 
 #if !TARGET_IPHONE_SIMULATOR
 
+static AVCaptureVideoOrientation Angle2AVCaptureVideoOrientation(int deviceOrientation);
+static AVCaptureVideoOrientation UIDeviceOrientation2AVCaptureVideoOrientation( UIDeviceOrientation orientation );
+
 // AVCaptureVideoPreviewLayer with AVCaptureSession creation
 @interface AVCaptureVideoPreviewLayerEx : AVCaptureVideoPreviewLayer
 
@@ -132,7 +135,8 @@ static void capture_queue_cleanup(void* p) {
 	
 	/* Set the layer */
 	AVCaptureVideoPreviewLayer *previewLayer = (AVCaptureVideoPreviewLayer *)self.layer;
-	[previewLayer setOrientation:AVCaptureVideoOrientationPortrait];
+    AVCaptureVideoOrientation    orientation = UIDeviceOrientation2AVCaptureVideoOrientation([[UIDevice currentDevice] orientation]);
+	[previewLayer setOrientation:orientation];
 	[previewLayer setBackgroundColor:[[UIColor clearColor] CGColor]];
 	[previewLayer setOpaque:YES];
 	start_time=0;
@@ -358,7 +362,7 @@ static void capture_queue_cleanup(void* p) {
 	return 0;
 }
 
-static AVCaptureVideoOrientation deviceOrientation2AVCaptureVideoOrientation(int deviceOrientation) {
+static AVCaptureVideoOrientation Angle2AVCaptureVideoOrientation(int deviceOrientation) {
 	switch (deviceOrientation) {
 		case 0: return AVCaptureVideoOrientationPortrait;
 		case 90: return AVCaptureVideoOrientationLandscapeLeft;	
@@ -373,6 +377,30 @@ static AVCaptureVideoOrientation deviceOrientation2AVCaptureVideoOrientation(int
 	return AVCaptureVideoOrientationPortrait;
 }
 
+static AVCaptureVideoOrientation UIDeviceOrientation2AVCaptureVideoOrientation( UIDeviceOrientation orientation ) {
+    switch (orientation) {
+
+        case UIDeviceOrientationPortraitUpsideDown:
+            return AVCaptureVideoOrientationPortraitUpsideDown;
+
+            // see http://stackoverflow.com/questions/7845520/why-does-avcapturevideoorientation-landscape-modes-result-in-upside-down-still-i
+            // landscape left on UI means landscape right on AVCapture.
+        case UIDeviceOrientationLandscapeLeft:
+            return AVCaptureVideoOrientationLandscapeRight;
+
+        case UIDeviceOrientationLandscapeRight:
+            return AVCaptureVideoOrientationLandscapeLeft;
+
+        case UIDeviceOrientationFaceUp:
+        case UIDeviceOrientationPortrait:
+        case UIDeviceOrientationUnknown:
+        case UIDeviceOrientationFaceDown:
+        default:
+            return AVCaptureVideoOrientationPortrait;
+            break;
+    }
+}
+
 - (void)configureSize:(MSVideoSize) outputSize
           withSession:(AVCaptureSession *) session {
 	if (((outputSize.width * outputSize.height) == (MS_VIDEO_SIZE_1080P_W * MS_VIDEO_SIZE_1080P_H))
@@ -642,7 +670,7 @@ static int ioscapture_set_device_orientation_display (MSFilter *f, void *arg) {
 	if (thiz != NULL) {
 		AVCaptureVideoPreviewLayer *previewLayer = (AVCaptureVideoPreviewLayer *)thiz.layer;
 		if ([previewLayer isOrientationSupported])
-			previewLayer.orientation = deviceOrientation2AVCaptureVideoOrientation(*(int*)(arg));
+			previewLayer.orientation = Angle2AVCaptureVideoOrientation(*(int*)(arg));
 	}
 	return 0;
 }