mpeg4audio: correctly propagate meaningful error values
[libav.git] / libavcodec / mpeg4audio.c
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 Libav.
7 *
8 * Libav 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 * Libav 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 Libav; 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 */
33 static int parse_config_ALS(GetBitContext *gb, MPEG4AudioConfig *c)
34 {
35 if (get_bits_left(gb) < 112)
36 return AVERROR_INVALIDDATA;
37
38 if (get_bits_long(gb, 32) != MKBETAG('A','L','S','\0'))
39 return AVERROR_INVALIDDATA;
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 const int avpriv_mpeg4audio_sample_rates[16] = {
56 96000, 88200, 64000, 48000, 44100, 32000,
57 24000, 22050, 16000, 12000, 11025, 8000, 7350
58 };
59
60 const uint8_t ff_mpeg4audio_channels[8] = {
61 0, 1, 2, 3, 4, 5, 6, 8
62 };
63
64 static inline int get_object_type(GetBitContext *gb)
65 {
66 int object_type = get_bits(gb, 5);
67 if (object_type == AOT_ESCAPE)
68 object_type = 32 + get_bits(gb, 6);
69 return object_type;
70 }
71
72 static inline int get_sample_rate(GetBitContext *gb, int *index)
73 {
74 *index = get_bits(gb, 4);
75 return *index == 0x0f ? get_bits(gb, 24) :
76 avpriv_mpeg4audio_sample_rates[*index];
77 }
78
79 int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
80 int bit_size, int sync_extension)
81 {
82 GetBitContext gb;
83 int specific_config_bitindex, ret;
84
85 ret = init_get_bits(&gb, buf, bit_size);
86 if (ret < 0)
87 return ret;
88 c->object_type = get_object_type(&gb);
89 c->sample_rate = get_sample_rate(&gb, &c->sampling_index);
90 c->chan_config = get_bits(&gb, 4);
91 if (c->chan_config < FF_ARRAY_ELEMS(ff_mpeg4audio_channels))
92 c->channels = ff_mpeg4audio_channels[c->chan_config];
93 c->sbr = -1;
94 c->ps = -1;
95 if (c->object_type == AOT_SBR || (c->object_type == AOT_PS &&
96 // check for W6132 Annex YYYY draft MP3onMP4
97 !(show_bits(&gb, 3) & 0x03 && !(show_bits(&gb, 9) & 0x3F)))) {
98 if (c->object_type == AOT_PS)
99 c->ps = 1;
100 c->ext_object_type = AOT_SBR;
101 c->sbr = 1;
102 c->ext_sample_rate = get_sample_rate(&gb, &c->ext_sampling_index);
103 c->object_type = get_object_type(&gb);
104 if (c->object_type == AOT_ER_BSAC)
105 c->ext_chan_config = get_bits(&gb, 4);
106 } else {
107 c->ext_object_type = AOT_NULL;
108 c->ext_sample_rate = 0;
109 }
110 specific_config_bitindex = get_bits_count(&gb);
111
112 if (c->object_type == AOT_ALS) {
113 skip_bits(&gb, 5);
114 if (show_bits_long(&gb, 24) != MKBETAG('\0','A','L','S'))
115 skip_bits_long(&gb, 24);
116
117 specific_config_bitindex = get_bits_count(&gb);
118
119 ret = parse_config_ALS(&gb, c);
120 if (ret < 0)
121 return ret;
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 (get_bits_left(&gb) > 11 && get_bits(&gb, 11) == 0x548)
132 c->ps = get_bits1(&gb);
133 break;
134 } else
135 get_bits1(&gb); // skip 1 bit
136 }
137 }
138
139 //PS requires SBR
140 if (!c->sbr)
141 c->ps = 0;
142 //Limit implicit PS to the HE-AACv2 Profile
143 if ((c->ps == -1 && c->object_type != AOT_AAC_LC) || c->channels & ~0x01)
144 c->ps = 0;
145
146 return specific_config_bitindex;
147 }
148
149 static av_always_inline unsigned int copy_bits(PutBitContext *pb,
150 GetBitContext *gb,
151 int bits)
152 {
153 unsigned int el = get_bits(gb, bits);
154 put_bits(pb, bits, el);
155 return el;
156 }
157
158 int avpriv_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
159 {
160 int five_bit_ch, four_bit_ch, comment_size, bits;
161 int offset = put_bits_count(pb);
162
163 copy_bits(pb, gb, 10); //Tag, Object Type, Frequency
164 five_bit_ch = copy_bits(pb, gb, 4); //Front
165 five_bit_ch += copy_bits(pb, gb, 4); //Side
166 five_bit_ch += copy_bits(pb, gb, 4); //Back
167 four_bit_ch = copy_bits(pb, gb, 2); //LFE
168 four_bit_ch += copy_bits(pb, gb, 3); //Data
169 five_bit_ch += copy_bits(pb, gb, 4); //Coupling
170 if (copy_bits(pb, gb, 1)) //Mono Mixdown
171 copy_bits(pb, gb, 4);
172 if (copy_bits(pb, gb, 1)) //Stereo Mixdown
173 copy_bits(pb, gb, 4);
174 if (copy_bits(pb, gb, 1)) //Matrix Mixdown
175 copy_bits(pb, gb, 3);
176 for (bits = five_bit_ch*5+four_bit_ch*4; bits > 16; bits -= 16)
177 copy_bits(pb, gb, 16);
178 if (bits)
179 copy_bits(pb, gb, bits);
180 avpriv_align_put_bits(pb);
181 align_get_bits(gb);
182 comment_size = copy_bits(pb, gb, 8);
183 for (; comment_size > 0; comment_size--)
184 copy_bits(pb, gb, 8);
185
186 return put_bits_count(pb) - offset;
187 }