Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / mpeg4audio.c
CommitLineData
2ba45a60
DM
1/*
2 * MPEG-4 Audio common code
3 * Copyright (c) 2008 Baptiste Coudurier <baptiste.coudurier@free.fr>
4 * Copyright (c) 2009 Alex Converse <alex.converse@gmail.com>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23#include "get_bits.h"
24#include "put_bits.h"
25#include "mpeg4audio.h"
26
27/**
28 * Parse MPEG-4 audio configuration for ALS object type.
29 * @param[in] gb bit reader context
30 * @param[in] c MPEG4AudioConfig structure to fill
31 * @return on success 0 is returned, otherwise a value < 0
32 */
33static int parse_config_ALS(GetBitContext *gb, MPEG4AudioConfig *c)
34{
35 if (get_bits_left(gb) < 112)
36 return -1;
37
38 if (get_bits_long(gb, 32) != MKBETAG('A','L','S','\0'))
39 return -1;
40
41 // override AudioSpecificConfig channel configuration and sample rate
42 // which are buggy in old ALS conformance files
43 c->sample_rate = get_bits_long(gb, 32);
44
45 // skip number of samples
46 skip_bits_long(gb, 32);
47
48 // read number of channels
49 c->chan_config = 0;
50 c->channels = get_bits(gb, 16) + 1;
51
52 return 0;
53}
54
55/* XXX: make sure to update the copies in the different encoders if you change
56 * this table */
57const int avpriv_mpeg4audio_sample_rates[16] = {
58 96000, 88200, 64000, 48000, 44100, 32000,
59 24000, 22050, 16000, 12000, 11025, 8000, 7350
60};
61
62const uint8_t ff_mpeg4audio_channels[8] = {
63 0, 1, 2, 3, 4, 5, 6, 8
64};
65
66static inline int get_object_type(GetBitContext *gb)
67{
68 int object_type = get_bits(gb, 5);
69 if (object_type == AOT_ESCAPE)
70 object_type = 32 + get_bits(gb, 6);
71 return object_type;
72}
73
74static inline int get_sample_rate(GetBitContext *gb, int *index)
75{
76 *index = get_bits(gb, 4);
77 return *index == 0x0f ? get_bits(gb, 24) :
78 avpriv_mpeg4audio_sample_rates[*index];
79}
80
81int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
82 int bit_size, int sync_extension)
83{
84 GetBitContext gb;
85 int specific_config_bitindex;
86
87 if (bit_size <= 0 || init_get_bits(&gb, buf, bit_size) < 0)
88 return AVERROR_INVALIDDATA;
89 c->object_type = get_object_type(&gb);
90 c->sample_rate = get_sample_rate(&gb, &c->sampling_index);
91 c->chan_config = get_bits(&gb, 4);
92 if (c->chan_config < FF_ARRAY_ELEMS(ff_mpeg4audio_channels))
93 c->channels = ff_mpeg4audio_channels[c->chan_config];
94 c->sbr = -1;
95 c->ps = -1;
96 if (c->object_type == AOT_SBR || (c->object_type == AOT_PS &&
97 // check for W6132 Annex YYYY draft MP3onMP4
98 !(show_bits(&gb, 3) & 0x03 && !(show_bits(&gb, 9) & 0x3F)))) {
99 if (c->object_type == AOT_PS)
100 c->ps = 1;
101 c->ext_object_type = AOT_SBR;
102 c->sbr = 1;
103 c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
104 c->object_type = get_object_type(&gb);
105 if (c->object_type == AOT_ER_BSAC)
106 c->ext_chan_config = get_bits(&gb, 4);
107 } else {
108 c->ext_object_type = AOT_NULL;
109 c->ext_sample_rate = 0;
110 }
111 specific_config_bitindex = get_bits_count(&gb);
112
113 if (c->object_type == AOT_ALS) {
114 skip_bits(&gb, 5);
115 if (show_bits_long(&gb, 24) != MKBETAG('\0','A','L','S'))
116 skip_bits_long(&gb, 24);
117
118 specific_config_bitindex = get_bits_count(&gb);
119
120 if (parse_config_ALS(&gb, c))
121 return -1;
122 }
123
124 if (c->ext_object_type != AOT_SBR && sync_extension) {
125 while (get_bits_left(&gb) > 15) {
126 if (show_bits(&gb, 11) == 0x2b7) { // sync extension
127 get_bits(&gb, 11);
128 c->ext_object_type = get_object_type(&gb);
129 if (c->ext_object_type == AOT_SBR && (c->sbr = get_bits1(&gb)) == 1) {
130 c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
131 if (c->ext_sample_rate == c->sample_rate)
132 c->sbr = -1;
133 }
134 if (get_bits_left(&gb) > 11 && get_bits(&gb, 11) == 0x548)
135 c->ps = get_bits1(&gb);
136 break;
137 } else
138 get_bits1(&gb); // skip 1 bit
139 }
140 }
141
142 //PS requires SBR
143 if (!c->sbr)
144 c->ps = 0;
145 //Limit implicit PS to the HE-AACv2 Profile
146 if ((c->ps == -1 && c->object_type != AOT_AAC_LC) || c->channels & ~0x01)
147 c->ps = 0;
148
149 return specific_config_bitindex;
150}
151
152static av_always_inline unsigned int copy_bits(PutBitContext *pb,
153 GetBitContext *gb,
154 int bits)
155{
156 unsigned int el = get_bits(gb, bits);
157 put_bits(pb, bits, el);
158 return el;
159}
160
161int avpriv_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
162{
163 int five_bit_ch, four_bit_ch, comment_size, bits;
164 int offset = put_bits_count(pb);
165
166 copy_bits(pb, gb, 10); //Tag, Object Type, Frequency
167 five_bit_ch = copy_bits(pb, gb, 4); //Front
168 five_bit_ch += copy_bits(pb, gb, 4); //Side
169 five_bit_ch += copy_bits(pb, gb, 4); //Back
170 four_bit_ch = copy_bits(pb, gb, 2); //LFE
171 four_bit_ch += copy_bits(pb, gb, 3); //Data
172 five_bit_ch += copy_bits(pb, gb, 4); //Coupling
173 if (copy_bits(pb, gb, 1)) //Mono Mixdown
174 copy_bits(pb, gb, 4);
175 if (copy_bits(pb, gb, 1)) //Stereo Mixdown
176 copy_bits(pb, gb, 4);
177 if (copy_bits(pb, gb, 1)) //Matrix Mixdown
178 copy_bits(pb, gb, 3);
179 for (bits = five_bit_ch*5+four_bit_ch*4; bits > 16; bits -= 16)
180 copy_bits(pb, gb, 16);
181 if (bits)
182 copy_bits(pb, gb, bits);
183 avpriv_align_put_bits(pb);
184 align_get_bits(gb);
185 comment_size = copy_bits(pb, gb, 8);
186 for (; comment_size > 0; comment_size--)
187 copy_bits(pb, gb, 8);
188
189 return put_bits_count(pb) - offset;
190}