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authorTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
committerTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
commit8992cb1d0d07edc33d274f6d7924ecdf6f83d994 (patch)
tree3a2c86846b7eec8137c1507e623fc7018f13d453 /ffmpeg/libavcodec/celp_math.c
parent741fb4b9e135cfb161a749db88713229038577bb (diff)
making act segmenter
Diffstat (limited to 'ffmpeg/libavcodec/celp_math.c')
-rw-r--r--ffmpeg/libavcodec/celp_math.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/celp_math.c b/ffmpeg/libavcodec/celp_math.c
new file mode 100644
index 0000000..a96b1ae
--- /dev/null
+++ b/ffmpeg/libavcodec/celp_math.c
@@ -0,0 +1,126 @@
+/*
+ * Various fixed-point math operations
+ *
+ * Copyright (c) 2008 Vladimir Voroshilov
+ *
+ * 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 <inttypes.h>
+#include <limits.h>
+
+#include "libavutil/avassert.h"
+#include "avcodec.h"
+#include "mathops.h"
+#include "celp_math.h"
+#include "libavutil/common.h"
+
+static const uint16_t exp2a[]=
+{
+ 0, 1435, 2901, 4400, 5931, 7496, 9096, 10730,
+ 12400, 14106, 15850, 17632, 19454, 21315, 23216, 25160,
+ 27146, 29175, 31249, 33368, 35534, 37747, 40009, 42320,
+ 44682, 47095, 49562, 52082, 54657, 57289, 59979, 62727,
+};
+
+static const uint16_t exp2b[]=
+{
+ 3, 712, 1424, 2134, 2845, 3557, 4270, 4982,
+ 5696, 6409, 7124, 7839, 8554, 9270, 9986, 10704,
+ 11421, 12138, 12857, 13576, 14295, 15014, 15734, 16455,
+ 17176, 17898, 18620, 19343, 20066, 20790, 21514, 22238,
+};
+
+int ff_exp2(uint16_t power)
+{
+ unsigned int result= exp2a[power>>10] + 0x10000;
+
+ av_assert2(power <= 0x7fff);
+
+ result= (result<<3) + ((result*exp2b[(power>>5)&31])>>17);
+ return result + ((result*(power&31)*89)>>22);
+}
+
+/**
+ * Table used to compute log2(x)
+ *
+ * tab_log2[i] = (1<<15) * log2(1 + i/32), i=0..32
+ */
+static const uint16_t tab_log2[33] =
+{
+#ifdef G729_BITEXACT
+ 0, 1455, 2866, 4236, 5568, 6863, 8124, 9352,
+ 10549, 11716, 12855, 13967, 15054, 16117, 17156, 18172,
+ 19167, 20142, 21097, 22033, 22951, 23852, 24735, 25603,
+ 26455, 27291, 28113, 28922, 29716, 30497, 31266, 32023, 32767,
+#else
+ 4, 1459, 2870, 4240, 5572, 6867, 8127, 9355,
+ 10552, 11719, 12858, 13971, 15057, 16120, 17158, 18175,
+ 19170, 20145, 21100, 22036, 22954, 23854, 24738, 25605,
+ 26457, 27294, 28116, 28924, 29719, 30500, 31269, 32025, 32769,
+#endif
+};
+
+int ff_log2_q15(uint32_t value)
+{
+ uint8_t power_int;
+ uint8_t frac_x0;
+ uint16_t frac_dx;
+
+ // Stripping zeros from beginning
+ power_int = av_log2(value);
+ value <<= (31 - power_int);
+
+ // b31 is always non-zero now
+ frac_x0 = (value & 0x7c000000) >> 26; // b26-b31 and [32..63] -> [0..31]
+ frac_dx = (value & 0x03fff800) >> 11;
+
+ value = tab_log2[frac_x0];
+ value += (frac_dx * (tab_log2[frac_x0+1] - tab_log2[frac_x0])) >> 15;
+
+ return (power_int << 15) + value;
+}
+
+int64_t ff_dot_product(const int16_t *a, const int16_t *b, int length)
+{
+ int i;
+ int64_t sum = 0;
+
+ for (i = 0; i < length; i++)
+ sum += MUL16(a[i], b[i]);
+
+ return sum;
+}
+
+float ff_dot_productf(const float* a, const float* b, int length)
+{
+ float sum = 0;
+ int i;
+
+ for(i=0; i<length; i++)
+ sum += a[i] * b[i];
+
+ return sum;
+}
+
+void ff_celp_math_init(CELPMContext *c)
+{
+ c->dot_productf = ff_dot_productf;
+
+ if(HAVE_MIPSFPU)
+ ff_celp_math_init_mips(c);
+}