Allow hard-coding of the 32kB cubic-root table for AAC.

Originally committed as revision 22527 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 51 insertions, 0 deletions

diff --git a/libavcodec/cbrt_tablegen.h b/libavcodec/cbrt_tablegen.h
new file mode 100644
index 0000000000..930e513705
--- /dev/null
+++ b/libavcodec/cbrt_tablegen.h
@@ -0,0 +1,51 @@
+/*
+ * Header file for hardcoded AAC cube-root table
+ *
+ * Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef CBRT_TABLEGEN_H
+#define CBRT_TABLEGEN_H
+
+#include <stdint.h>
+#include <math.h>
+
+#if CONFIG_HARDCODED_TABLES
+#define cbrt_tableinit()
+#include "libavcodec/cbrt_tables.h"
+#else
+static uint32_t cbrt_tab[1 << 13];
+
+static void cbrt_tableinit(void)
+{
+    if (!cbrt_tab[(1<<13) - 1]) {
+        int i;
+        for (i = 0; i < 1<<13; i++) {
+            union {
+                float f;
+                uint32_t i;
+            } f;
+            f.f = cbrtf(i) * i;
+            cbrt_tab[i] = f.i;
+        }
+    }
+}
+#endif /* CONFIG_HARDCODED_TABLES */
+
+#endif /* CBRT_TABLEGEN_H */