gst/gststructure.c: Fix fraction list fixation code. Take the fraction with the smallest difference with the target i...

Original commit message from CVS:
* gst/gststructure.c:
(gst_structure_fixate_field_nearest_fraction):
Fix fraction list fixation code. Take the fraction with the smallest
difference with the target instead of the first one in the list.
* tests/check/gst/gststructure.c: (GST_START_TEST),
(gst_structure_suite):
Added test to verify correct fraction list fixation behaviour.

ChangeLog

@@ -1,3 +1,14 @@
+2007-09-04  Wim Taymans  <wim.taymans@gmail.com>
+
+	* gst/gststructure.c:
+	(gst_structure_fixate_field_nearest_fraction):
+	Fix fraction list fixation code. Take the fraction with the smallest
+	difference with the target instead of the first one in the list.
+
+	* tests/check/gst/gststructure.c: (GST_START_TEST),
+	(gst_structure_suite):
+	Added test to verify correct fraction list fixation behaviour.
+
 2007-09-02  Tim-Philipp Müller  <tim at centricular dot net>
 
 	* win32/common/libgstreamer.def:

gst/gststructure.c

@@ -2167,23 +2167,23 @@ gst_structure_fixate_field_nearest_fraction (GstStructure * structure,
 
     gst_value_set_fraction (&target, target_numerator, target_denominator);
 
+    best = NULL;
+
     n = gst_value_list_get_size (value);
     for (i = 0; i < n; i++) {
       list_value = gst_value_list_get_value (value, i);
       if (G_VALUE_TYPE (list_value) == GST_TYPE_FRACTION) {
-        if (best == NULL) {
-          best = list_value;
-          gst_value_set_fraction (&best_diff, 0, 1);
-        } else {
-          if (gst_value_compare (list_value, &target) == GST_VALUE_LESS_THAN)
-            gst_value_fraction_subtract (&cur_diff, &target, list_value);
-          else
-            gst_value_fraction_subtract (&cur_diff, list_value, &target);
 
-          if (gst_value_compare (&cur_diff, &best_diff) == GST_VALUE_LESS_THAN) {
+        if (gst_value_compare (list_value, &target) == GST_VALUE_LESS_THAN)
-            best = list_value;
+          gst_value_fraction_subtract (&cur_diff, &target, list_value);
-            g_value_copy (&cur_diff, &best_diff);
+        else
-          }
+          gst_value_fraction_subtract (&cur_diff, list_value, &target);
+
+        if (!best
+            || gst_value_compare (&cur_diff,
+                &best_diff) == GST_VALUE_LESS_THAN) {
+          best = list_value;
+          g_value_copy (&cur_diff, &best_diff);
         }
       }
     }
@@ -2196,6 +2196,5 @@ gst_structure_fixate_field_nearest_fraction (GstStructure * structure,
     g_value_unset (&target);
     return res;
   }
-
   return FALSE;
 }

tests/check/gst/gststructure.c

@@ -204,6 +204,44 @@ GST_START_TEST (test_fixate)
 
 GST_END_TEST;
 
+GST_START_TEST (test_fixate_frac_list)
+{
+  GstStructure *s;
+  GValue list = { 0 };
+  GValue frac = { 0 };
+  gchar *str;
+  gint num, denom;
+
+  g_value_init (&list, GST_TYPE_LIST);
+  g_value_init (&frac, GST_TYPE_FRACTION);
+
+  gst_value_set_fraction (&frac, 30, 1);
+  gst_value_list_append_value (&list, &frac);
+  gst_value_set_fraction (&frac, 15, 1);
+  gst_value_list_append_value (&list, &frac);
+  gst_value_set_fraction (&frac, 10, 1);
+  gst_value_list_append_value (&list, &frac);
+
+  s = gst_structure_new ("name", NULL);
+  gst_structure_set_value (s, "frac", &list);
+  g_value_unset (&frac);
+  g_value_unset (&list);
+
+  str = gst_structure_to_string (s);
+  GST_DEBUG ("list %s", str);
+  g_free (str);
+
+  /* fixate to the nearest fraction, this should give 15/1 */
+  fail_unless (gst_structure_fixate_field_nearest_fraction (s, "frac", 14, 1));
+
+  fail_unless (gst_structure_get_fraction (s, "frac", &num, &denom));
+  fail_unless (num == 15);
+  fail_unless (denom == 1);
+
+  gst_structure_free (s);
+}
+
+GST_END_TEST;
 
 Suite *
 gst_structure_suite (void)
@@ -217,6 +255,7 @@ gst_structure_suite (void)
   tcase_add_test (tc_chain, test_complete_structure);
   tcase_add_test (tc_chain, test_structure_new);
   tcase_add_test (tc_chain, test_fixate);
+  tcase_add_test (tc_chain, test_fixate_frac_list);
   return s;
 }