Linux video capture: rotate image if V4L2_IN_ST_VFLIP is set

media/video/capture/linux/video_capture_device_linux.cc

Index: media/video/capture/linux/video_capture_device_linux.cc
diff --git a/media/video/capture/linux/video_capture_device_linux.cc b/media/video/capture/linux/video_capture_device_linux.cc
index 0192daba3e7e2807a827edd1e6f35a9e8512bbcf..e7f2e23e1edd1d04ba4669428bb8e70091090ada 100644
--- a/media/video/capture/linux/video_capture_device_linux.cc
+++ b/media/video/capture/linux/video_capture_device_linux.cc
@@ -250,6 +250,32 @@ void VideoCaptureDeviceLinux::OnAllocateAndStart(int width,
     return;
   }
 
+  // Check sensor orientation.
+  struct v4l2_input first_input;
+  first_input.index = 0;  // First input type.
+  if (HANDLE_EINTR(ioctl(device_fd_.get(),
+                         VIDIOC_ENUMINPUT, &first_input)) == 0) {
+    struct v4l2_input second_input;
+    second_input.index = 1;
+    if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_ENUMINPUT,
+                           &second_input)) < 0) {
+      // Only one input type
+      if (first_input.status & V4L2_IN_ST_VFLIP) {
+        DVLOG(1) << "Sensor is flipped vertically, rotating 180 deg.";
+        if (!(first_input.status & V4L2_IN_ST_HFLIP)) {
+          DVLOG(1) << "Sensor is only flipped vertically, "
+                      "image will be mirrored";
+        }
+        SetRotation(180);
+      }
+    } else {
+      // More than one input type, don't try to fix sensor orientation.
+      DVLOG(1) << "Video capture device has more than one input type";
+    }
+  } else {
+    DVLOG(1) << "Failed to enumerate video input";
+  }
+
   // Set format and frame size now.
   v4l2_format video_fmt;
   memset(&video_fmt, 0, sizeof(v4l2_format));