DIRAC Decoder stable version, MMX support removed.

Look for MMX_DISABLED to find the disabled functions.

Authors of this code are Marco Gerards <marco@gnu.org> and David Conrad <lessen42@gmail.com>
With changes from Jordi Ortiz <nenjordi@gmail.com>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 115 insertions, 0 deletions

diff --git a/libavcodec/dirac_arith.c b/libavcodec/dirac_arith.c
new file mode 100644
index 0000000..ae40beb
--- /dev/null
+++ b/libavcodec/dirac_arith.c
@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2007 Marco Gerards <marco@gnu.org>
+ * Copyright (C) 2009 David Conrad
+ *
+ * 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
+ */
+
+/**
+ * @file libavcodec/dirac_arith.c
+ * Arithmetic decoder for Dirac
+ * @author Marco Gerards <marco@gnu.org>
+ */
+
+#include "dirac_arith.h"
+
+const uint16_t ff_dirac_prob[256] = {
+    0,    2,    5,    8,    11,   15,   20,   24,
+    29,   35,   41,   47,   53,   60,   67,   74,
+    82,   89,   97,   106,  114,  123,  132,  141,
+    150,  160,  170,  180,  190,  201,  211,  222,
+    233,  244,  256,  267,  279,  291,  303,  315,
+    327,  340,  353,  366,  379,  392,  405,  419,
+    433,  447,  461,  475,  489,  504,  518,  533,
+    548,  563,  578,  593,  609,  624,  640,  656,
+    672,  688,  705,  721,  738,  754,  771,  788,
+    805,  822,  840,  857,  875,  892,  910,  928,
+    946,  964,  983,  1001, 1020, 1038, 1057, 1076,
+    1095, 1114, 1133, 1153, 1172, 1192, 1211, 1231,
+    1251, 1271, 1291, 1311, 1332, 1352, 1373, 1393,
+    1414, 1435, 1456, 1477, 1498, 1520, 1541, 1562,
+    1584, 1606, 1628, 1649, 1671, 1694, 1716, 1738,
+    1760, 1783, 1806, 1828, 1851, 1874, 1897, 1920,
+    1935, 1942, 1949, 1955, 1961, 1968, 1974, 1980,
+    1985, 1991, 1996, 2001, 2006, 2011, 2016, 2021,
+    2025, 2029, 2033, 2037, 2040, 2044, 2047, 2050,
+    2053, 2056, 2058, 2061, 2063, 2065, 2066, 2068,
+    2069, 2070, 2071, 2072, 2072, 2072, 2072, 2072,
+    2072, 2071, 2070, 2069, 2068, 2066, 2065, 2063,
+    2060, 2058, 2055, 2052, 2049, 2045, 2042, 2038,
+    2033, 2029, 2024, 2019, 2013, 2008, 2002, 1996,
+    1989, 1982, 1975, 1968, 1960, 1952, 1943, 1934,
+    1925, 1916, 1906, 1896, 1885, 1874, 1863, 1851,
+    1839, 1827, 1814, 1800, 1786, 1772, 1757, 1742,
+    1727, 1710, 1694, 1676, 1659, 1640, 1622, 1602,
+    1582, 1561, 1540, 1518, 1495, 1471, 1447, 1422,
+    1396, 1369, 1341, 1312, 1282, 1251, 1219, 1186,
+    1151, 1114, 1077, 1037, 995,  952,  906,  857,
+    805,  750,  690,  625,  553,  471,  376,  255
+};
+
+const uint8_t ff_dirac_next_ctx[DIRAC_CTX_COUNT] = {
+    [CTX_ZPZN_F1]   = CTX_ZP_F2,
+    [CTX_ZPNN_F1]   = CTX_ZP_F2,
+    [CTX_ZP_F2]     = CTX_ZP_F3,
+    [CTX_ZP_F3]     = CTX_ZP_F4,
+    [CTX_ZP_F4]     = CTX_ZP_F5,
+    [CTX_ZP_F5]     = CTX_ZP_F6,
+    [CTX_ZP_F6]     = CTX_ZP_F6,
+    [CTX_NPZN_F1]   = CTX_NP_F2,
+    [CTX_NPNN_F1]   = CTX_NP_F2,
+    [CTX_NP_F2]     = CTX_NP_F3,
+    [CTX_NP_F3]     = CTX_NP_F4,
+    [CTX_NP_F4]     = CTX_NP_F5,
+    [CTX_NP_F5]     = CTX_NP_F6,
+    [CTX_NP_F6]     = CTX_NP_F6,
+    [CTX_DELTA_Q_F] = CTX_DELTA_Q_F,
+};
+
+int16_t ff_dirac_prob_branchless[256][2];
+
+void ff_dirac_init_arith_decoder(DiracArith *c, GetBitContext *gb, int length)
+{
+    int i;
+    align_get_bits(gb);
+
+    length = FFMIN(length, get_bits_left(gb)/8);
+
+    c->bytestream     = gb->buffer + get_bits_count(gb)/8;
+    c->bytestream_end = c->bytestream + length;
+    skip_bits_long(gb, length*8);
+
+    c->low = 0;
+    for (i = 0; i < 4; i++) {
+        c->low <<= 8;
+        if (c->bytestream < c->bytestream_end)
+            c->low |= *c->bytestream++;
+        else
+            c->low |= 0xff;
+    }
+
+    c->counter = -16;
+    c->range   = 0xffff;
+
+    for (i = 0; i < 256; i++) {
+        ff_dirac_prob_branchless[i][0] =  ff_dirac_prob[255-i];
+        ff_dirac_prob_branchless[i][1] = -ff_dirac_prob[i];
+    }
+
+    for (i = 0; i < DIRAC_CTX_COUNT; i++)
+        c->contexts[i] = 0x8000;
+}