1 files changed, 76 insertions, 0 deletions
diff --git a/libavcodec/cos_tablegen.c b/libavcodec/cos_tablegen.c
new file mode 100644
index 0000000000..5e52c482c6
--- /dev/null
+++ b/libavcodec/cos_tablegen.c
@@ -0,0 +1,76 @@
+/*
+ * Generate a header file for hardcoded ff_cos_* tables
+ *
+ * Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
+ *
+ * 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 <stdio.h>
+#include <string.h>
+#include <math.h>
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+#define BITS 16
+#define FLOATFMT "%.18e"
+#define FIXEDFMT "%6d"
+
+static int clip_f15(int v)
+{
+    return v < -32767 ? -32767 :
+           v >  32767 ?  32767 :
+           v;
+}
+
+static void printval(double val, int fixed)
+{
+    if (fixed)
+        printf(" "FIXEDFMT",", clip_f15(lrint(val * (double)(1<<15))));
+    else
+        printf(" "FLOATFMT",", val);
+
+}
+
+int main(int argc, char *argv[])
+{
+    int i, j;
+    int do_sin = argc > 1 && !strcmp(argv[1], "sin");
+    int fixed  = argc > 1 &&  strstr(argv[1], "fixed");
+    double (*func)(double) = do_sin ? sin : cos;
+
+    printf("/* This file was automatically generated. */\n");
+    printf("#define CONFIG_FFT_FLOAT %d\n", !fixed);
+    printf("#include \"libavcodec/%s\"\n", do_sin ? "rdft.h" : "fft.h");
+    for (i = 4; i <= BITS; i++) {
+        int m = 1 << i;
+        double freq = 2*M_PI/m;
+        printf("%s(%i) = {\n   ", do_sin ? "SINTABLE" : "COSTABLE", m);
+        for (j = 0; j < m/2 - 1; j++) {
+            int idx = j > m/4 ? m/2 - j : j;
+            if (do_sin && j >= m/4)
+                idx = m/4 - j;
+            printval(func(idx*freq), fixed);
+            if ((j & 3) == 3)
+                printf("\n   ");
+        }
+        printval(func(do_sin ? -(m/4 - 1)*freq : freq), fixed);
+        printf("\n};\n");
+    }
+    return 0;
+}