v4l2: don't add the same interlace mode twice

Some drivers modify the interlace mode to progressive, no matter what
input you give them, make sure that we don't add the same interlace mode
twice.

diff --git a/sys/v4l2/gstv4l2object.c b/sys/v4l2/gstv4l2object.c
index 1f4b84e..816b42c 100644 (file)
--- a/sys/v4l2/gstv4l2object.c
+++ b/sys/v4l2/gstv4l2object.c
@@ -1753,7 +1753,7 @@ gst_v4l2_object_add_interlace_mode (GstV4l2Object * v4l2object,
 {
   struct v4l2_format fmt;
   GValue interlace_formats = { 0, };
-  GstVideoInterlaceMode interlace_mode;
+  GstVideoInterlaceMode interlace_mode, prev = -1;
 
   const gchar *mode_strings[] = { "progressive",
     "interleaved",
@@ -1784,6 +1784,7 @@ gst_v4l2_object_add_interlace_mode (GstV4l2Object * v4l2object,
     g_value_init (&interlace_enum, G_TYPE_STRING);
     g_value_set_string (&interlace_enum, mode_strings[interlace_mode]);
     gst_value_list_append_and_take_value (&interlace_formats, &interlace_enum);
+    prev = interlace_mode;
   }
 
   memset (&fmt, 0, sizeof (fmt));
@@ -1794,7 +1795,8 @@ gst_v4l2_object_add_interlace_mode (GstV4l2Object * v4l2object,
   fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
 
   if (gst_v4l2_object_try_fmt (v4l2object, &fmt) == 0 &&
-      gst_v4l2_object_get_interlace_mode (fmt.fmt.pix.field, &interlace_mode)) {
+      gst_v4l2_object_get_interlace_mode (fmt.fmt.pix.field, &interlace_mode) &&
+      prev != interlace_mode) {
     GValue interlace_enum = { 0, };
     g_value_init (&interlace_enum, G_TYPE_STRING);
     g_value_set_string (&interlace_enum, mode_strings[interlace_mode]);