blob: b4620acf6b973fed0a8b94cb3fe9230a1b9455e3
1 | /* |
2 | * LucasArts VIMA decoder |
3 | * Copyright (c) 2012 Paul B Mahol |
4 | * |
5 | * This file is part of FFmpeg. |
6 | * |
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. |
11 | * |
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. |
16 | * |
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 |
20 | */ |
21 | |
22 | /** |
23 | * @file |
24 | * LucasArts VIMA audio decoder |
25 | * @author Paul B Mahol |
26 | */ |
27 | |
28 | #include "libavutil/channel_layout.h" |
29 | |
30 | #include "adpcm_data.h" |
31 | #include "avcodec.h" |
32 | #include "get_bits.h" |
33 | #include "internal.h" |
34 | |
35 | static int predict_table_init = 0; |
36 | static uint16_t predict_table[5786 * 2]; |
37 | |
38 | static const uint8_t size_table[] = { |
39 | 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, |
40 | 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, |
41 | 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, |
42 | 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, |
43 | 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, |
44 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7 |
45 | }; |
46 | |
47 | static const int8_t index_table1[] = { |
48 | -1, 4, -1, 4 |
49 | }; |
50 | |
51 | static const int8_t index_table2[] = { |
52 | -1, -1, 2, 6, -1, -1, 2, 6 |
53 | }; |
54 | |
55 | static const int8_t index_table3[] = { |
56 | -1, -1, -1, -1, 1, 2, 4, 6, -1, -1, -1, -1, 1, 2, 4, 6 |
57 | }; |
58 | |
59 | static const int8_t index_table4[] = { |
60 | -1, -1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 2, 2, 4, 5, 6, |
61 | -1, -1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 2, 2, 4, 5, 6 |
62 | }; |
63 | |
64 | static const int8_t index_table5[] = { |
65 | -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
66 | 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 5, 5, 6, 6, |
67 | -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
68 | 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 5, 5, 6, 6 |
69 | }; |
70 | |
71 | static const int8_t index_table6[] = { |
72 | -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
73 | -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
74 | 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, |
75 | 2, 2, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, |
76 | -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
77 | -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
78 | 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, |
79 | 2, 2, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6 |
80 | }; |
81 | |
82 | static const int8_t *const step_index_tables[] = { |
83 | index_table1, index_table2, index_table3, |
84 | index_table4, index_table5, index_table6 |
85 | }; |
86 | |
87 | static av_cold int decode_init(AVCodecContext *avctx) |
88 | { |
89 | int start_pos; |
90 | |
91 | avctx->sample_fmt = AV_SAMPLE_FMT_S16; |
92 | |
93 | if (predict_table_init) |
94 | return 0; |
95 | |
96 | for (start_pos = 0; start_pos < 64; start_pos++) { |
97 | unsigned int dest_pos, table_pos; |
98 | |
99 | for (table_pos = 0, dest_pos = start_pos; |
100 | table_pos < FF_ARRAY_ELEMS(ff_adpcm_step_table); |
101 | table_pos++, dest_pos += 64) { |
102 | int put = 0, count, table_value; |
103 | |
104 | table_value = ff_adpcm_step_table[table_pos]; |
105 | for (count = 32; count != 0; count >>= 1) { |
106 | if (start_pos & count) |
107 | put += table_value; |
108 | table_value >>= 1; |
109 | } |
110 | predict_table[dest_pos] = put; |
111 | } |
112 | } |
113 | predict_table_init = 1; |
114 | |
115 | return 0; |
116 | } |
117 | |
118 | static int decode_frame(AVCodecContext *avctx, void *data, |
119 | int *got_frame_ptr, AVPacket *pkt) |
120 | { |
121 | GetBitContext gb; |
122 | AVFrame *frame = data; |
123 | int16_t pcm_data[2]; |
124 | uint32_t samples; |
125 | int8_t channel_hint[2]; |
126 | int ret, chan; |
127 | int channels = 1; |
128 | |
129 | if (pkt->size < 13) |
130 | return AVERROR_INVALIDDATA; |
131 | |
132 | if ((ret = init_get_bits8(&gb, pkt->data, pkt->size)) < 0) |
133 | return ret; |
134 | |
135 | samples = get_bits_long(&gb, 32); |
136 | if (samples == 0xffffffff) { |
137 | skip_bits_long(&gb, 32); |
138 | samples = get_bits_long(&gb, 32); |
139 | } |
140 | |
141 | if (samples > pkt->size * 2) |
142 | return AVERROR_INVALIDDATA; |
143 | |
144 | channel_hint[0] = get_sbits(&gb, 8); |
145 | if (channel_hint[0] & 0x80) { |
146 | channel_hint[0] = ~channel_hint[0]; |
147 | channels = 2; |
148 | } |
149 | avctx->channels = channels; |
150 | avctx->channel_layout = (channels == 2) ? AV_CH_LAYOUT_STEREO |
151 | : AV_CH_LAYOUT_MONO; |
152 | pcm_data[0] = get_sbits(&gb, 16); |
153 | if (channels > 1) { |
154 | channel_hint[1] = get_sbits(&gb, 8); |
155 | pcm_data[1] = get_sbits(&gb, 16); |
156 | } |
157 | |
158 | frame->nb_samples = samples; |
159 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
160 | return ret; |
161 | |
162 | for (chan = 0; chan < channels; chan++) { |
163 | uint16_t *dest = (uint16_t *)frame->data[0] + chan; |
164 | int step_index = channel_hint[chan]; |
165 | int output = pcm_data[chan]; |
166 | int sample; |
167 | |
168 | for (sample = 0; sample < samples; sample++) { |
169 | int lookup_size, lookup, highbit, lowbits; |
170 | |
171 | step_index = av_clip(step_index, 0, 88); |
172 | lookup_size = size_table[step_index]; |
173 | lookup = get_bits(&gb, lookup_size); |
174 | highbit = 1 << (lookup_size - 1); |
175 | lowbits = highbit - 1; |
176 | |
177 | if (lookup & highbit) |
178 | lookup ^= highbit; |
179 | else |
180 | highbit = 0; |
181 | |
182 | if (lookup == lowbits) { |
183 | output = get_sbits(&gb, 16); |
184 | } else { |
185 | int predict_index, diff; |
186 | |
187 | predict_index = (lookup << (7 - lookup_size)) | (step_index << 6); |
188 | predict_index = av_clip(predict_index, 0, 5785); |
189 | diff = predict_table[predict_index]; |
190 | if (lookup) |
191 | diff += ff_adpcm_step_table[step_index] >> (lookup_size - 1); |
192 | if (highbit) |
193 | diff = -diff; |
194 | |
195 | output = av_clip_int16(output + diff); |
196 | } |
197 | |
198 | *dest = output; |
199 | dest += channels; |
200 | |
201 | step_index += step_index_tables[lookup_size - 2][lookup]; |
202 | } |
203 | } |
204 | |
205 | *got_frame_ptr = 1; |
206 | |
207 | return pkt->size; |
208 | } |
209 | |
210 | AVCodec ff_adpcm_vima_decoder = { |
211 | .name = "adpcm_vima", |
212 | .long_name = NULL_IF_CONFIG_SMALL("LucasArts VIMA audio"), |
213 | .type = AVMEDIA_TYPE_AUDIO, |
214 | .id = AV_CODEC_ID_ADPCM_VIMA, |
215 | .init = decode_init, |
216 | .decode = decode_frame, |
217 | .capabilities = AV_CODEC_CAP_DR1, |
218 | }; |
219 |