3 * Copyright (c) 2011 Justin Ruggles
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 static void ac3_exponent_min_c(uint8_t *exp, int num_reuse_blocks, int nb_coefs)
29 if (!num_reuse_blocks)
32 for (i = 0; i < nb_coefs; i++) {
33 uint8_t min_exp = *exp;
34 uint8_t *exp1 = exp + 256;
35 for (blk = 0; blk < num_reuse_blocks; blk++) {
36 uint8_t next_exp = *exp1;
37 if (next_exp < min_exp)
45 static int ac3_max_msb_abs_int16_c(const int16_t *src, int len)
48 for (i = 0; i < len; i++)
53 static void ac3_lshift_int16_c(int16_t *src, unsigned int len,
56 uint32_t *src32 = (uint32_t *)src;
57 const uint32_t mask = ~(((1 << shift) - 1) << 16);
60 for (i = 0; i < len; i += 8) {
61 src32[i ] = (src32[i ] << shift) & mask;
62 src32[i+1] = (src32[i+1] << shift) & mask;
63 src32[i+2] = (src32[i+2] << shift) & mask;
64 src32[i+3] = (src32[i+3] << shift) & mask;
65 src32[i+4] = (src32[i+4] << shift) & mask;
66 src32[i+5] = (src32[i+5] << shift) & mask;
67 src32[i+6] = (src32[i+6] << shift) & mask;
68 src32[i+7] = (src32[i+7] << shift) & mask;
72 static void ac3_rshift_int32_c(int32_t *src, unsigned int len,
88 static void float_to_fixed24_c(int32_t *dst, const float *src, unsigned int len)
90 const float scale = 1 << 24;
92 *dst++ = lrintf(*src++ * scale);
93 *dst++ = lrintf(*src++ * scale);
94 *dst++ = lrintf(*src++ * scale);
95 *dst++ = lrintf(*src++ * scale);
96 *dst++ = lrintf(*src++ * scale);
97 *dst++ = lrintf(*src++ * scale);
98 *dst++ = lrintf(*src++ * scale);
99 *dst++ = lrintf(*src++ * scale);
104 av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
106 c->ac3_exponent_min = ac3_exponent_min_c;
107 c->ac3_max_msb_abs_int16 = ac3_max_msb_abs_int16_c;
108 c->ac3_lshift_int16 = ac3_lshift_int16_c;
109 c->ac3_rshift_int32 = ac3_rshift_int32_c;
110 c->float_to_fixed24 = float_to_fixed24_c;
113 ff_ac3dsp_init_arm(c, bit_exact);
115 ff_ac3dsp_init_x86(c, bit_exact);