[PATCH v2 4/4] Add support to libv4l to use orientation from VIDIOC_ENUMINPUT

[Adam Baker <linux@baker-net.org.uk>]

Add check to libv4l of the sensor orientation as reported by
VIDIOC_ENUMINPUT

Signed-off-by: Adam Baker <linux@baker-net.org.uk>

---
diff -r a647c2dfa989 v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c
--- a/v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c	Tue Jan 20 11:25:54 2009 +0100
+++ b/v4l2-apps/lib/libv4l/libv4lconvert/libv4lconvert.c	Sun Mar 29 22:59:56 2009 +0100
@@ -29,6 +29,11 @@
 #define MIN(a,b) (((a)<(b))?(a):(b))
 #define ARRAY_SIZE(x) ((int)sizeof(x)/(int)sizeof((x)[0]))
 
+/* Workaround this potentially being missing from videodev2.h */
+#ifndef V4L2_IN_ST_VFLIP
+#define V4L2_IN_ST_VFLIP       0x00000020 /* Output is flipped vertically */
+#endif
+
 /* Note for proper functioning of v4lconvert_enum_fmt the first entries in
   supported_src_pixfmts must match with the entries in supported_dst_pixfmts */
 #define SUPPORTED_DST_PIXFMTS \
@@ -134,6 +139,7 @@
   int i, j;
   struct v4lconvert_data *data = calloc(1, sizeof(struct v4lconvert_data));
   struct v4l2_capability cap;
+  struct v4l2_input input;
 
   if (!data)
     return NULL;
@@ -161,6 +167,13 @@
 
   /* Check if this cam has any special flags */
   data->flags = v4lconvert_get_flags(data->fd);
+  if ((syscall(SYS_ioctl, fd, VIDIOC_G_INPUT, &input.index) == 0) &&
+      (syscall(SYS_ioctl, fd, VIDIOC_ENUMINPUT, &input) == 0)) {
+    /* Don't yet support independent HFLIP and VFLIP so getting
+     * image the right way up is highest priority. */
+    if (input.status & V4L2_IN_ST_VFLIP)
+      data->flags |= V4LCONVERT_ROTATE_180;
+  }
   if (syscall(SYS_ioctl, fd, VIDIOC_QUERYCAP, &cap) == 0) {
     if (!strcmp((char *)cap.driver, "uvcvideo"))
       data->flags |= V4LCONVERT_IS_UVC;