1/*
2 * Copyright (c) 2012
3 *      MIPS Technologies, Inc., California.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the MIPS Technologies, Inc., nor the names of its
14 *    contributors may be used to endorse or promote products derived from
15 *    this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * Author:  Stanislav Ocovaj (socovaj@mips.com)
30 *
31 * AC3 fixed-point decoder for MIPS platforms
32 *
33 * This file is part of FFmpeg.
34 *
35 * FFmpeg is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU Lesser General Public
37 * License as published by the Free Software Foundation; either
38 * version 2.1 of the License, or (at your option) any later version.
39 *
40 * FFmpeg is distributed in the hope that it will be useful,
41 * but WITHOUT ANY WARRANTY; without even the implied warranty of
42 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
43 * Lesser General Public License for more details.
44 *
45 * You should have received a copy of the GNU Lesser General Public
46 * License along with FFmpeg; if not, write to the Free Software
47 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
48 */
49
50#define FFT_FLOAT 0
51#define USE_FIXED 1
52#include "ac3dec.h"
53#include "codec_internal.h"
54
55
56static const int end_freq_inv_tab[8] =
57{
58    50529027, 44278013, 39403370, 32292987, 27356480, 23729101, 20951060, 18755316
59};
60
61static void scale_coefs (
62    int32_t *dst,
63    const int32_t *src,
64    int dynrng,
65    int len)
66{
67    int i, shift;
68    unsigned mul, round;
69    int temp, temp1, temp2, temp3, temp4, temp5, temp6, temp7;
70
71    mul = (dynrng & 0x1f) + 0x20;
72    shift = 4 - (sign_extend(dynrng, 9) >> 5);
73    if (shift > 0 ) {
74      round = 1 << (shift-1);
75      for (i=0; i<len; i+=8) {
76
77          temp = src[i] * mul;
78          temp1 = src[i+1] * mul;
79          temp = temp + round;
80          temp2 = src[i+2] * mul;
81
82          temp1 = temp1 + round;
83          dst[i] = temp >> shift;
84          temp3 = src[i+3] * mul;
85          temp2 = temp2 + round;
86
87          dst[i+1] = temp1 >> shift;
88          temp4 = src[i + 4] * mul;
89          temp3 = temp3 + round;
90          dst[i+2] = temp2 >> shift;
91
92          temp5 = src[i+5] * mul;
93          temp4 = temp4 + round;
94          dst[i+3] = temp3 >> shift;
95          temp6 = src[i+6] * mul;
96
97          dst[i+4] = temp4 >> shift;
98          temp5 = temp5 + round;
99          temp7 = src[i+7] * mul;
100          temp6 = temp6 + round;
101
102          dst[i+5] = temp5 >> shift;
103          temp7 = temp7 + round;
104          dst[i+6] = temp6 >> shift;
105          dst[i+7] = temp7 >> shift;
106
107      }
108    } else {
109      shift = -shift;
110      mul <<= shift;
111      for (i=0; i<len; i+=8) {
112
113          dst[i]   = src[i  ] * mul;
114          dst[i+1] = src[i+1] * mul;
115          dst[i+2] = src[i+2] * mul;
116          dst[i+3] = src[i+3] * mul;
117          dst[i+4] = src[i+4] * mul;
118          dst[i+5] = src[i+5] * mul;
119          dst[i+6] = src[i+6] * mul;
120          dst[i+7] = src[i+7] * mul;
121      }
122    }
123}
124
125/**
126 * Downmix samples from original signal to stereo or mono (this is for 16-bit samples
127 * and fixed point decoder - original (for 32-bit samples) is in ac3dsp.c).
128 */
129static void ac3_downmix_c_fixed16(int16_t **samples, int16_t **matrix,
130                                  int out_ch, int in_ch, int len)
131{
132    int i, j;
133    int v0, v1;
134    if (out_ch == 2) {
135        for (i = 0; i < len; i++) {
136            v0 = v1 = 0;
137            for (j = 0; j < in_ch; j++) {
138                v0 += samples[j][i] * matrix[0][j];
139                v1 += samples[j][i] * matrix[1][j];
140            }
141            samples[0][i] = (v0+2048)>>12;
142            samples[1][i] = (v1+2048)>>12;
143        }
144    } else if (out_ch == 1) {
145        for (i = 0; i < len; i++) {
146            v0 = 0;
147            for (j = 0; j < in_ch; j++)
148                v0 += samples[j][i] * matrix[0][j];
149            samples[0][i] = (v0+2048)>>12;
150        }
151    }
152}
153
154#include "eac3dec.c"
155#include "ac3dec.c"
156
157static const AVOption options[] = {
158    { "cons_noisegen", "enable consistent noise generation", OFFSET(consistent_noise_generation), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },
159    { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },
160    { "heavy_compr", "enable heavy dynamic range compression", OFFSET(heavy_compression), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },
161    { "downmix", "Request a specific channel layout from the decoder", OFFSET(downmix_layout), AV_OPT_TYPE_CHLAYOUT, {.str = NULL}, .flags = PAR },
162    { NULL},
163};
164
165static const AVClass ac3_decoder_class = {
166    .class_name = "Fixed-Point AC-3 Decoder",
167    .item_name  = av_default_item_name,
168    .option     = options,
169    .version    = LIBAVUTIL_VERSION_INT,
170};
171
172const FFCodec ff_ac3_fixed_decoder = {
173    .p.name         = "ac3_fixed",
174    .p.long_name    = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
175    .p.type         = AVMEDIA_TYPE_AUDIO,
176    .p.id           = AV_CODEC_ID_AC3,
177    .p.priv_class   = &ac3_decoder_class,
178    .priv_data_size = sizeof (AC3DecodeContext),
179    .init           = ac3_decode_init,
180    .close          = ac3_decode_end,
181    FF_CODEC_DECODE_CB(ac3_decode_frame),
182    .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
183                      AV_CODEC_CAP_DR1,
184    .p.sample_fmts  = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
185                                                      AV_SAMPLE_FMT_NONE },
186    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
187};
188