diff --git a/vcsi/vcsi.py b/vcsi/vcsi.py
index 5e8f8af..65c1da9 100755
--- a/vcsi/vcsi.py
+++ b/vcsi/vcsi.py
@@ -170,6 +170,17 @@ def compute_display_resolution(self):
         """
         self.sample_width = int(self.video_stream["width"])
         self.sample_height = int(self.video_stream["height"])
+
+        # videos recorded with a smartphone may have a "rotate" flag
+        try:
+            rotation = int(self.video_stream["tags"]["rotate"])
+        except KeyError:
+            rotation = None
+
+        if rotation == 90:
+            # swap width and height
+            self.sample_width, self.sample_height = self.sample_height, self.sample_width
+
         sample_aspect_ratio = "1:1"
         try:
             sample_aspect_ratio = self.video_stream["sample_aspect_ratio"]