1 files changed, 62 insertions, 0 deletions
diff --git a/libavcodec/wma_common.c b/libavcodec/wma_common.c
new file mode 100644
index 0000000000..6ba5337f6a
--- /dev/null
+++ b/libavcodec/wma_common.c
@@ -0,0 +1,62 @@
+/*
+ * common code shared by all WMA variants
+ *
+ * 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 "libavutil/attributes.h"
+#include "wma_common.h"
+
+/**
+ *@brief Get the samples per frame for this stream.
+ *@param sample_rate output sample_rate
+ *@param version wma version
+ *@param decode_flags codec compression features
+ *@return log2 of the number of output samples per frame
+ */
+int av_cold ff_wma_get_frame_len_bits(int sample_rate, int version,
+                                      unsigned int decode_flags)
+{
+
+    int frame_len_bits;
+
+    if (sample_rate <= 16000) {
+        frame_len_bits = 9;
+    } else if (sample_rate <= 22050 ||
+             (sample_rate <= 32000 && version == 1)) {
+        frame_len_bits = 10;
+    } else if (sample_rate <= 48000 || version < 3) {
+        frame_len_bits = 11;
+    } else if (sample_rate <= 96000) {
+        frame_len_bits = 12;
+    } else {
+        frame_len_bits = 13;
+    }
+
+    if (version == 3) {
+        int tmp = decode_flags & 0x6;
+        if (tmp == 0x2) {
+            ++frame_len_bits;
+        } else if (tmp == 0x4) {
+            --frame_len_bits;
+        } else if (tmp == 0x6) {
+            frame_len_bits -= 2;
+        }
+    }
+
+    return frame_len_bits;
+}