[FFmpeg-devel] [PATCH v2 08/16] avcodec/dca: add math helpers and fixed point DCT
foo86
foobaz86 at gmail.com
Thu Jan 21 19:47:17 CET 2016
---
libavcodec/dcadct.c | 362 +++++++++++++++++++++++++++++++++++++++++++++++++++
libavcodec/dcadct.h | 32 +++++
libavcodec/dcamath.h | 54 ++++++++
3 files changed, 448 insertions(+)
create mode 100644 libavcodec/dcadct.c
create mode 100644 libavcodec/dcadct.h
create mode 100644 libavcodec/dcamath.h
diff --git a/libavcodec/dcadct.c b/libavcodec/dcadct.c
new file mode 100644
index 0000000..1082aa8
--- /dev/null
+++ b/libavcodec/dcadct.c
@@ -0,0 +1,362 @@
+/*
+ * Copyright (C) 2016 foo86
+ *
+ * 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 "libavutil/common.h"
+
+#include "dcadct.h"
+#include "dcamath.h"
+
+static void sum_a(const int *input, int *output, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ output[i] = input[2 * i] + input[2 * i + 1];
+}
+
+static void sum_b(const int *input, int *output, int len)
+{
+ int i;
+
+ output[0] = input[0];
+ for (i = 1; i < len; i++)
+ output[i] = input[2 * i] + input[2 * i - 1];
+}
+
+static void sum_c(const int *input, int *output, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ output[i] = input[2 * i];
+}
+
+static void sum_d(const int *input, int *output, int len)
+{
+ int i;
+
+ output[0] = input[1];
+ for (i = 1; i < len; i++)
+ output[i] = input[2 * i - 1] + input[2 * i + 1];
+}
+
+static void dct_a(const int *input, int *output)
+{
+ static const int cos_mod[8][8] = {
+ { 8348215, 8027397, 7398092, 6484482, 5321677, 3954362, 2435084, 822227 },
+ { 8027397, 5321677, 822227, -3954362, -7398092, -8348215, -6484482, -2435084 },
+ { 7398092, 822227, -6484482, -8027397, -2435084, 5321677, 8348215, 3954362 },
+ { 6484482, -3954362, -8027397, 822227, 8348215, 2435084, -7398092, -5321677 },
+ { 5321677, -7398092, -2435084, 8348215, -822227, -8027397, 3954362, 6484482 },
+ { 3954362, -8348215, 5321677, 2435084, -8027397, 6484482, 822227, -7398092 },
+ { 2435084, -6484482, 8348215, -7398092, 3954362, 822227, -5321677, 8027397 },
+ { 822227, -2435084, 3954362, -5321677, 6484482, -7398092, 8027397, -8348215 }
+ };
+
+ int i, j;
+
+ for (i = 0; i < 8; i++) {
+ int64_t res = 0;
+ for (j = 0; j < 8; j++)
+ res += (int64_t)cos_mod[i][j] * input[j];
+ output[i] = norm23(res);
+ }
+}
+
+static void dct_b(const int *input, int *output)
+{
+ static const int cos_mod[8][7] = {
+ { 8227423, 7750063, 6974873, 5931642, 4660461, 3210181, 1636536 },
+ { 6974873, 3210181, -1636536, -5931642, -8227423, -7750063, -4660461 },
+ { 4660461, -3210181, -8227423, -5931642, 1636536, 7750063, 6974873 },
+ { 1636536, -7750063, -4660461, 5931642, 6974873, -3210181, -8227423 },
+ { -1636536, -7750063, 4660461, 5931642, -6974873, -3210181, 8227423 },
+ { -4660461, -3210181, 8227423, -5931642, -1636536, 7750063, -6974873 },
+ { -6974873, 3210181, 1636536, -5931642, 8227423, -7750063, 4660461 },
+ { -8227423, 7750063, -6974873, 5931642, -4660461, 3210181, -1636536 }
+ };
+
+ int i, j;
+
+ for (i = 0; i < 8; i++) {
+ int64_t res = input[0] * (INT64_C(1) << 23);
+ for (j = 0; j < 7; j++)
+ res += (int64_t)cos_mod[i][j] * input[1 + j];
+ output[i] = norm23(res);
+ }
+}
+
+static void mod_a(const int *input, int *output)
+{
+ static const int cos_mod[16] = {
+ 4199362, 4240198, 4323885, 4454708,
+ 4639772, 4890013, 5221943, 5660703,
+ -6245623, -7040975, -8158494, -9809974,
+ -12450076, -17261920, -28585092, -85479984
+ };
+
+ int i, k;
+
+ for (i = 0; i < 8; i++)
+ output[i] = mul23(cos_mod[i], input[i] + input[8 + i]);
+
+ for (i = 8, k = 7; i < 16; i++, k--)
+ output[i] = mul23(cos_mod[i], input[k] - input[8 + k]);
+}
+
+static void mod_b(int *input, int *output)
+{
+ static const int cos_mod[8] = {
+ 4214598, 4383036, 4755871, 5425934,
+ 6611520, 8897610, 14448934, 42791536
+ };
+
+ int i, k;
+
+ for (i = 0; i < 8; i++)
+ input[8 + i] = mul23(cos_mod[i], input[8 + i]);
+
+ for (i = 0; i < 8; i++)
+ output[i] = input[i] + input[8 + i];
+
+ for (i = 8, k = 7; i < 16; i++, k--)
+ output[i] = input[k] - input[8 + k];
+}
+
+static void mod_c(const int *input, int *output)
+{
+ static const int cos_mod[32] = {
+ 1048892, 1051425, 1056522, 1064244,
+ 1074689, 1087987, 1104313, 1123884,
+ 1146975, 1173922, 1205139, 1241133,
+ 1282529, 1330095, 1384791, 1447815,
+ -1520688, -1605358, -1704360, -1821051,
+ -1959964, -2127368, -2332183, -2587535,
+ -2913561, -3342802, -3931480, -4785806,
+ -6133390, -8566050, -14253820, -42727120
+ };
+
+ int i, k;
+
+ for (i = 0; i < 16; i++)
+ output[i] = mul23(cos_mod[i], input[i] + input[16 + i]);
+
+ for (i = 16, k = 15; i < 32; i++, k--)
+ output[i] = mul23(cos_mod[i], input[k] - input[16 + k]);
+}
+
+static void clp_v(int *input, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ input[i] = clip23(input[i]);
+}
+
+static void imdct_half_32(int32_t *output, const int32_t *input)
+{
+ int buf_a[32], buf_b[32];
+ int i, k, mag, shift, round;
+
+ mag = 0;
+ for (i = 0; i < 32; i++)
+ mag += abs(input[i]);
+
+ shift = mag > 0x400000 ? 2 : 0;
+ round = shift > 0 ? 1 << (shift - 1) : 0;
+
+ for (i = 0; i < 32; i++)
+ buf_a[i] = (input[i] + round) >> shift;
+
+ sum_a(buf_a, buf_b + 0, 16);
+ sum_b(buf_a, buf_b + 16, 16);
+ clp_v(buf_b, 32);
+
+ sum_a(buf_b + 0, buf_a + 0, 8);
+ sum_b(buf_b + 0, buf_a + 8, 8);
+ sum_c(buf_b + 16, buf_a + 16, 8);
+ sum_d(buf_b + 16, buf_a + 24, 8);
+ clp_v(buf_a, 32);
+
+ dct_a(buf_a + 0, buf_b + 0);
+ dct_b(buf_a + 8, buf_b + 8);
+ dct_b(buf_a + 16, buf_b + 16);
+ dct_b(buf_a + 24, buf_b + 24);
+ clp_v(buf_b, 32);
+
+ mod_a(buf_b + 0, buf_a + 0);
+ mod_b(buf_b + 16, buf_a + 16);
+ clp_v(buf_a, 32);
+
+ mod_c(buf_a, buf_b);
+
+ for (i = 0; i < 32; i++)
+ buf_b[i] = clip23(buf_b[i] * (1 << shift));
+
+ for (i = 0, k = 31; i < 16; i++, k--) {
+ output[ i] = clip23(buf_b[i] - buf_b[k]);
+ output[16 + i] = clip23(buf_b[i] + buf_b[k]);
+ }
+}
+
+static void mod64_a(const int *input, int *output)
+{
+ static const int cos_mod[32] = {
+ 4195568, 4205700, 4226086, 4256977,
+ 4298755, 4351949, 4417251, 4495537,
+ 4587901, 4695690, 4820557, 4964534,
+ 5130115, 5320382, 5539164, 5791261,
+ -6082752, -6421430, -6817439, -7284203,
+ -7839855, -8509474, -9328732, -10350140,
+ -11654242, -13371208, -15725922, -19143224,
+ -24533560, -34264200, -57015280, -170908480
+ };
+
+ int i, k;
+
+ for (i = 0; i < 16; i++)
+ output[i] = mul23(cos_mod[i], input[i] + input[16 + i]);
+
+ for (i = 16, k = 15; i < 32; i++, k--)
+ output[i] = mul23(cos_mod[i], input[k] - input[16 + k]);
+}
+
+static void mod64_b(int *input, int *output)
+{
+ static const int cos_mod[16] = {
+ 4199362, 4240198, 4323885, 4454708,
+ 4639772, 4890013, 5221943, 5660703,
+ 6245623, 7040975, 8158494, 9809974,
+ 12450076, 17261920, 28585092, 85479984
+ };
+
+ int i, k;
+
+ for (i = 0; i < 16; i++)
+ input[16 + i] = mul23(cos_mod[i], input[16 + i]);
+
+ for (i = 0; i < 16; i++)
+ output[i] = input[i] + input[16 + i];
+
+ for (i = 16, k = 15; i < 32; i++, k--)
+ output[i] = input[k] - input[16 + k];
+}
+
+static void mod64_c(const int *input, int *output)
+{
+ static const int cos_mod[64] = {
+ 741511, 741958, 742853, 744199,
+ 746001, 748262, 750992, 754197,
+ 757888, 762077, 766777, 772003,
+ 777772, 784105, 791021, 798546,
+ 806707, 815532, 825054, 835311,
+ 846342, 858193, 870912, 884554,
+ 899181, 914860, 931667, 949686,
+ 969011, 989747, 1012012, 1035941,
+ -1061684, -1089412, -1119320, -1151629,
+ -1186595, -1224511, -1265719, -1310613,
+ -1359657, -1413400, -1472490, -1537703,
+ -1609974, -1690442, -1780506, -1881904,
+ -1996824, -2128058, -2279225, -2455101,
+ -2662128, -2909200, -3208956, -3579983,
+ -4050785, -4667404, -5509372, -6726913,
+ -8641940, -12091426, -20144284, -60420720
+ };
+
+ int i, k;
+
+ for (i = 0; i < 32; i++)
+ output[i] = mul23(cos_mod[i], input[i] + input[32 + i]);
+
+ for (i = 32, k = 31; i < 64; i++, k--)
+ output[i] = mul23(cos_mod[i], input[k] - input[32 + k]);
+}
+
+static void imdct_half_64(int32_t *output, const int32_t *input)
+{
+ int buf_a[64], buf_b[64];
+ int i, k, mag, shift, round;
+
+ mag = 0;
+ for (i = 0; i < 64; i++)
+ mag += abs(input[i]);
+
+ shift = mag > 0x400000 ? 2 : 0;
+ round = shift > 0 ? 1 << (shift - 1) : 0;
+
+ for (i = 0; i < 64; i++)
+ buf_a[i] = (input[i] + round) >> shift;
+
+ sum_a(buf_a, buf_b + 0, 32);
+ sum_b(buf_a, buf_b + 32, 32);
+ clp_v(buf_b, 64);
+
+ sum_a(buf_b + 0, buf_a + 0, 16);
+ sum_b(buf_b + 0, buf_a + 16, 16);
+ sum_c(buf_b + 32, buf_a + 32, 16);
+ sum_d(buf_b + 32, buf_a + 48, 16);
+ clp_v(buf_a, 64);
+
+ sum_a(buf_a + 0, buf_b + 0, 8);
+ sum_b(buf_a + 0, buf_b + 8, 8);
+ sum_c(buf_a + 16, buf_b + 16, 8);
+ sum_d(buf_a + 16, buf_b + 24, 8);
+ sum_c(buf_a + 32, buf_b + 32, 8);
+ sum_d(buf_a + 32, buf_b + 40, 8);
+ sum_c(buf_a + 48, buf_b + 48, 8);
+ sum_d(buf_a + 48, buf_b + 56, 8);
+ clp_v(buf_b, 64);
+
+ dct_a(buf_b + 0, buf_a + 0);
+ dct_b(buf_b + 8, buf_a + 8);
+ dct_b(buf_b + 16, buf_a + 16);
+ dct_b(buf_b + 24, buf_a + 24);
+ dct_b(buf_b + 32, buf_a + 32);
+ dct_b(buf_b + 40, buf_a + 40);
+ dct_b(buf_b + 48, buf_a + 48);
+ dct_b(buf_b + 56, buf_a + 56);
+ clp_v(buf_a, 64);
+
+ mod_a(buf_a + 0, buf_b + 0);
+ mod_b(buf_a + 16, buf_b + 16);
+ mod_b(buf_a + 32, buf_b + 32);
+ mod_b(buf_a + 48, buf_b + 48);
+ clp_v(buf_b, 64);
+
+ mod64_a(buf_b + 0, buf_a + 0);
+ mod64_b(buf_b + 32, buf_a + 32);
+ clp_v(buf_a, 64);
+
+ mod64_c(buf_a, buf_b);
+
+ for (i = 0; i < 64; i++)
+ buf_b[i] = clip23(buf_b[i] * (1 << shift));
+
+ for (i = 0, k = 63; i < 32; i++, k--) {
+ output[ i] = clip23(buf_b[i] - buf_b[k]);
+ output[32 + i] = clip23(buf_b[i] + buf_b[k]);
+ }
+}
+
+av_cold void ff_dcadct_init(DCADCTContext *c)
+{
+ c->imdct_half[0] = imdct_half_32;
+ c->imdct_half[1] = imdct_half_64;
+}
diff --git a/libavcodec/dcadct.h b/libavcodec/dcadct.h
new file mode 100644
index 0000000..518c9f9
--- /dev/null
+++ b/libavcodec/dcadct.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2016 foo86
+ *
+ * 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 AVCODEC_DCADCT_H
+#define AVCODEC_DCADCT_H
+
+#include "libavutil/common.h"
+
+typedef struct DCADCTContext {
+ void (*imdct_half[2])(int32_t *output, const int32_t *input);
+} DCADCTContext;
+
+av_cold void ff_dcadct_init(DCADCTContext *c);
+
+#endif
diff --git a/libavcodec/dcamath.h b/libavcodec/dcamath.h
new file mode 100644
index 0000000..e05b8a9
--- /dev/null
+++ b/libavcodec/dcamath.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2016 foo86
+ *
+ * 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 AVCODEC_DCAMATH_H
+#define AVCODEC_DCAMATH_H
+
+#include "libavutil/intmath.h"
+
+static inline int32_t norm__(int64_t a, int bits)
+{
+ if (bits > 0)
+ return (int32_t)((a + (INT64_C(1) << (bits - 1))) >> bits);
+ else
+ return (int32_t)a;
+}
+
+static inline int32_t mul__(int32_t a, int32_t b, int bits)
+{
+ return norm__((int64_t)a * b, bits);
+}
+
+static inline int32_t norm13(int64_t a) { return norm__(a, 13); }
+static inline int32_t norm16(int64_t a) { return norm__(a, 16); }
+static inline int32_t norm20(int64_t a) { return norm__(a, 20); }
+static inline int32_t norm21(int64_t a) { return norm__(a, 21); }
+static inline int32_t norm23(int64_t a) { return norm__(a, 23); }
+
+static inline int32_t mul15(int32_t a, int32_t b) { return mul__(a, b, 15); }
+static inline int32_t mul16(int32_t a, int32_t b) { return mul__(a, b, 16); }
+static inline int32_t mul17(int32_t a, int32_t b) { return mul__(a, b, 17); }
+static inline int32_t mul22(int32_t a, int32_t b) { return mul__(a, b, 22); }
+static inline int32_t mul23(int32_t a, int32_t b) { return mul__(a, b, 23); }
+static inline int32_t mul31(int32_t a, int32_t b) { return mul__(a, b, 31); }
+
+static inline int32_t clip23(int32_t a) { return av_clip_intp2(a, 23); }
+
+#endif
--
2.1.4
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