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

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

libavcodec/Makefile

@@ -757,6 +757,7 @@ $(SUBDIR)%_tables.h: $(SUBDIR)%_tablegen$(HOSTEXESUF)
 	$(M)./$< > $@
 
 ifdef CONFIG_HARDCODED_TABLES
+$(SUBDIR)aac.o: $(SUBDIR)cbrt_tables.h
 $(SUBDIR)mdct.o: $(SUBDIR)mdct_tables.h
 $(SUBDIR)mpegaudiodec.o: $(SUBDIR)mpegaudio_tables.h
 $(SUBDIR)motionpixels.o: $(SUBDIR)motionpixels_tables.h

libavcodec/aac.c

@@ -86,6 +86,7 @@
 #include "aac.h"
 #include "aactab.h"
 #include "aacdectab.h"
+#include "cbrt_tablegen.h"
 #include "sbr.h"
 #include "aacsbr.h"
 #include "mpeg4audio.h"
@@ -108,8 +109,6 @@ union float754 {
 static VLC vlc_scalefactors;
 static VLC vlc_spectral[11];
 
-static uint32_t cbrt_tab[1<<13];
-
 static const char overread_err[] = "Input buffer exhausted before END element found\n";
 
 static ChannelElement *get_che(AACContext *ac, int type, int elem_id)
@@ -574,13 +573,7 @@ static av_cold int aac_decode_init(AVCodecContext *avccontext)
     ff_init_ff_sine_windows(10);
     ff_init_ff_sine_windows( 7);
 
-    if (!cbrt_tab[(1<<13) - 1]) {
-        for (i = 0; i < 1<<13; i++) {
-            union float754 f;
-            f.f = cbrtf(i) * i;
-            cbrt_tab[i] = f.i;
-        }
-    }
+    cbrt_tableinit();
 
     return 0;
 }

libavcodec/cbrt_tablegen.c

@@ -0,0 +1,42 @@
+/*
+ * Generate a 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
+ */
+
+#include <stdlib.h>
+#define CONFIG_HARDCODED_TABLES 0
+#include "cbrt_tablegen.h"
+#include "tableprint.h"
+
+void tableinit(void)
+{
+    cbrt_tableinit();
+}
+
+const struct tabledef tables[] = {
+    {
+        "static const uint32_t cbrt_tab[1<<13]",
+        write_uint32_array,
+        cbrt_tab,
+        1 << 13,
+        0
+    },
+    { NULL }
+};

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 */