libv4l: add support for fixing upside down images to libv4lconvert

From: Hans de Goede <j.w.r.degoede@hhs.nl>

Add support to libv4lconvert to flipping the image for upside down mounted
sensors, libv4lconvert will do this automatically if the webcam sets a
flag in its query_fmt reply indicating that this is necessary, this fixes
the upside down image on Philips SPC200NC images

Priority: normal

Signed-off-by: Hans de Goede <j.w.r.degoede@hhs.nl>

1 files changed, 60 insertions, 0 deletions

diff --git a/v4l2-apps/lib/libv4l/libv4lconvert/flip.c b/v4l2-apps/lib/libv4l/libv4lconvert/flip.c
new file mode 100644
index 000000000..de76ecc9a
--- /dev/null
+++ b/v4l2-apps/lib/libv4l/libv4lconvert/flip.c
@@ -0,0 +1,60 @@
+/*
+
+# RGB / YUV flip routines
+
+#             (C) 2008 Hans de Goede <j.w.r.degoede@hhs.nl>
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*/
+
+#include "libv4lconvert-priv.h"
+
+void v4lconvert_flip_rgbbgr24(const unsigned char *src, unsigned char *dst,
+  int width, int height)
+{
+  int i;
+
+  src += 3 * width * height - 3;
+
+  for (i = 0; i < width * height; i++) {
+    dst[0] = src[0];
+    dst[1] = src[1];
+    dst[2] = src[2];
+    dst += 3;
+    src -= 3;
+  }
+}
+
+void v4lconvert_flip_yuv420(const unsigned char *src, unsigned char *dst,
+  int width, int height)
+{
+  int i;
+
+  /* First flip x and y of the Y plane */
+  src += width * height - 1;
+  for (i = 0; i < width * height; i++)
+    *dst++ = *src--;
+
+  /* Now flip the U plane */
+  src += width * height * 5 / 4;
+  for (i = 0; i < width * height / 4; i++)
+    *dst++ = *src--;
+
+  /* Last flip the V plane */
+  src += width * height / 2;
+  for (i = 0; i < width * height / 4; i++)
+    *dst++ = *src--;
+}