lavu: add av_ctz() for trailing zero bit count

1 files changed, 39 insertions, 0 deletions

diff --git a/libavutil/intmath.c b/libavutil/intmath.c
new file mode 100644
index 0000000000..8db425c6e9
--- /dev/null
+++ b/libavutil/intmath.c
@@ -0,0 +1,39 @@
+/*
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "intmath.h"
+
+/* undef these to get the function prototypes from common.h */
+#undef av_log2
+#undef av_log2_16bit
+#include "common.h"
+
+int av_log2(unsigned v)
+{
+    return ff_log2(v);
+}
+
+int av_log2_16bit(unsigned v)
+{
+    return ff_log2_16bit(v);
+}
+
+int av_ctz(int v)
+{
+    return ff_ctz(v);
+}