return rectantle box instead of circle when there is only a single face (#226)

ppgan/apps/first_order_predictor.py

@@ -154,6 +154,7 @@ class FirstOrderPredictor(BasePredictor):
             results.append({'rec': rec, 'predict': predictions})
 
         out_frame = []
+
         for i in range(len(driving_video)):
             frame = source_image.copy()
             for result in results:
@@ -162,6 +163,9 @@ class FirstOrderPredictor(BasePredictor):
                 w = x2 - x1
                 out = result['predict'][i] * 255.0
                 out = cv2.resize(out.astype(np.uint8), (x2 - x1, y2 - y1))
+                if len(results) == 1:
+                    frame[y1:y2, x1:x2] = out
+                else:
                     patch = np.zeros(frame.shape).astype('uint8')
                     patch[y1:y2, x1:x2] = out
                     mask = np.zeros(frame.shape[:2]).astype('uint8')