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mace.c
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1 /*
2  * MACE decoder
3  * Copyright (c) 2002 Laszlo Torok <torokl@alpha.dfmk.hu>
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  * MACE decoder.
25  */
26 
27 #include "avcodec.h"
28 #include "internal.h"
29 #include "libavutil/common.h"
30 
31 /*
32  * Adapted to libavcodec by Francois Revol <revol@free.fr>
33  * (removed 68k REG stuff, changed types, added some statics and consts,
34  * libavcodec api, context stuff, interlaced stereo out).
35  */
36 
37 static const int16_t MACEtab1[] = {-13, 8, 76, 222, 222, 76, 8, -13};
38 
39 static const int16_t MACEtab3[] = {-18, 140, 140, -18};
40 
41 static const int16_t MACEtab2[][4] = {
42  { 37, 116, 206, 330}, { 39, 121, 216, 346},
43  { 41, 127, 225, 361}, { 42, 132, 235, 377},
44  { 44, 137, 245, 392}, { 46, 144, 256, 410},
45  { 48, 150, 267, 428}, { 51, 157, 280, 449},
46  { 53, 165, 293, 470}, { 55, 172, 306, 490},
47  { 58, 179, 319, 511}, { 60, 187, 333, 534},
48  { 63, 195, 348, 557}, { 66, 205, 364, 583},
49  { 69, 214, 380, 609}, { 72, 223, 396, 635},
50  { 75, 233, 414, 663}, { 79, 244, 433, 694},
51  { 82, 254, 453, 725}, { 86, 265, 472, 756},
52  { 90, 278, 495, 792}, { 94, 290, 516, 826},
53  { 98, 303, 538, 862}, { 102, 316, 562, 901},
54  { 107, 331, 588, 942}, { 112, 345, 614, 983},
55  { 117, 361, 641, 1027}, { 122, 377, 670, 1074},
56  { 127, 394, 701, 1123}, { 133, 411, 732, 1172},
57  { 139, 430, 764, 1224}, { 145, 449, 799, 1280},
58  { 152, 469, 835, 1337}, { 159, 490, 872, 1397},
59  { 166, 512, 911, 1459}, { 173, 535, 951, 1523},
60  { 181, 558, 993, 1590}, { 189, 584, 1038, 1663},
61  { 197, 610, 1085, 1738}, { 206, 637, 1133, 1815},
62  { 215, 665, 1183, 1895}, { 225, 695, 1237, 1980},
63  { 235, 726, 1291, 2068}, { 246, 759, 1349, 2161},
64  { 257, 792, 1409, 2257}, { 268, 828, 1472, 2357},
65  { 280, 865, 1538, 2463}, { 293, 903, 1606, 2572},
66  { 306, 944, 1678, 2688}, { 319, 986, 1753, 2807},
67  { 334, 1030, 1832, 2933}, { 349, 1076, 1914, 3065},
68  { 364, 1124, 1999, 3202}, { 380, 1174, 2088, 3344},
69  { 398, 1227, 2182, 3494}, { 415, 1281, 2278, 3649},
70  { 434, 1339, 2380, 3811}, { 453, 1398, 2486, 3982},
71  { 473, 1461, 2598, 4160}, { 495, 1526, 2714, 4346},
72  { 517, 1594, 2835, 4540}, { 540, 1665, 2961, 4741},
73  { 564, 1740, 3093, 4953}, { 589, 1818, 3232, 5175},
74  { 615, 1898, 3375, 5405}, { 643, 1984, 3527, 5647},
75  { 671, 2072, 3683, 5898}, { 701, 2164, 3848, 6161},
76  { 733, 2261, 4020, 6438}, { 766, 2362, 4199, 6724},
77  { 800, 2467, 4386, 7024}, { 836, 2578, 4583, 7339},
78  { 873, 2692, 4786, 7664}, { 912, 2813, 5001, 8008},
79  { 952, 2938, 5223, 8364}, { 995, 3070, 5457, 8739},
80  { 1039, 3207, 5701, 9129}, { 1086, 3350, 5956, 9537},
81  { 1134, 3499, 6220, 9960}, { 1185, 3655, 6497, 10404},
82  { 1238, 3818, 6788, 10869}, { 1293, 3989, 7091, 11355},
83  { 1351, 4166, 7407, 11861}, { 1411, 4352, 7738, 12390},
84  { 1474, 4547, 8084, 12946}, { 1540, 4750, 8444, 13522},
85  { 1609, 4962, 8821, 14126}, { 1680, 5183, 9215, 14756},
86  { 1756, 5415, 9626, 15415}, { 1834, 5657, 10057, 16104},
87  { 1916, 5909, 10505, 16822}, { 2001, 6173, 10975, 17574},
88  { 2091, 6448, 11463, 18356}, { 2184, 6736, 11974, 19175},
89  { 2282, 7037, 12510, 20032}, { 2383, 7351, 13068, 20926},
90  { 2490, 7679, 13652, 21861}, { 2601, 8021, 14260, 22834},
91  { 2717, 8380, 14897, 23854}, { 2838, 8753, 15561, 24918},
92  { 2965, 9144, 16256, 26031}, { 3097, 9553, 16982, 27193},
93  { 3236, 9979, 17740, 28407}, { 3380, 10424, 18532, 29675},
94  { 3531, 10890, 19359, 31000}, { 3688, 11375, 20222, 32382},
95  { 3853, 11883, 21125, 32767}, { 4025, 12414, 22069, 32767},
96  { 4205, 12967, 23053, 32767}, { 4392, 13546, 24082, 32767},
97  { 4589, 14151, 25157, 32767}, { 4793, 14783, 26280, 32767},
98  { 5007, 15442, 27452, 32767}, { 5231, 16132, 28678, 32767},
99  { 5464, 16851, 29957, 32767}, { 5708, 17603, 31294, 32767},
100  { 5963, 18389, 32691, 32767}, { 6229, 19210, 32767, 32767},
101  { 6507, 20067, 32767, 32767}, { 6797, 20963, 32767, 32767},
102  { 7101, 21899, 32767, 32767}, { 7418, 22876, 32767, 32767},
103  { 7749, 23897, 32767, 32767}, { 8095, 24964, 32767, 32767},
104  { 8456, 26078, 32767, 32767}, { 8833, 27242, 32767, 32767},
105  { 9228, 28457, 32767, 32767}, { 9639, 29727, 32767, 32767}
106 };
107 
108 static const int16_t MACEtab4[][2] = {
109  { 64, 216}, { 67, 226}, { 70, 236}, { 74, 246},
110  { 77, 257}, { 80, 268}, { 84, 280}, { 88, 294},
111  { 92, 307}, { 96, 321}, { 100, 334}, { 104, 350},
112  { 109, 365}, { 114, 382}, { 119, 399}, { 124, 416},
113  { 130, 434}, { 136, 454}, { 142, 475}, { 148, 495},
114  { 155, 519}, { 162, 541}, { 169, 564}, { 176, 590},
115  { 185, 617}, { 193, 644}, { 201, 673}, { 210, 703},
116  { 220, 735}, { 230, 767}, { 240, 801}, { 251, 838},
117  { 262, 876}, { 274, 914}, { 286, 955}, { 299, 997},
118  { 312, 1041}, { 326, 1089}, { 341, 1138}, { 356, 1188},
119  { 372, 1241}, { 388, 1297}, { 406, 1354}, { 424, 1415},
120  { 443, 1478}, { 462, 1544}, { 483, 1613}, { 505, 1684},
121  { 527, 1760}, { 551, 1838}, { 576, 1921}, { 601, 2007},
122  { 628, 2097}, { 656, 2190}, { 686, 2288}, { 716, 2389},
123  { 748, 2496}, { 781, 2607}, { 816, 2724}, { 853, 2846},
124  { 891, 2973}, { 930, 3104}, { 972, 3243}, { 1016, 3389},
125  { 1061, 3539}, { 1108, 3698}, { 1158, 3862}, { 1209, 4035},
126  { 1264, 4216}, { 1320, 4403}, { 1379, 4599}, { 1441, 4806},
127  { 1505, 5019}, { 1572, 5244}, { 1642, 5477}, { 1715, 5722},
128  { 1792, 5978}, { 1872, 6245}, { 1955, 6522}, { 2043, 6813},
129  { 2134, 7118}, { 2229, 7436}, { 2329, 7767}, { 2432, 8114},
130  { 2541, 8477}, { 2655, 8854}, { 2773, 9250}, { 2897, 9663},
131  { 3026, 10094}, { 3162, 10546}, { 3303, 11016}, { 3450, 11508},
132  { 3604, 12020}, { 3765, 12556}, { 3933, 13118}, { 4108, 13703},
133  { 4292, 14315}, { 4483, 14953}, { 4683, 15621}, { 4892, 16318},
134  { 5111, 17046}, { 5339, 17807}, { 5577, 18602}, { 5826, 19433},
135  { 6086, 20300}, { 6358, 21205}, { 6642, 22152}, { 6938, 23141},
136  { 7248, 24173}, { 7571, 25252}, { 7909, 26380}, { 8262, 27557},
137  { 8631, 28786}, { 9016, 30072}, { 9419, 31413}, { 9839, 32767},
138  { 10278, 32767}, { 10737, 32767}, { 11216, 32767}, { 11717, 32767},
139  { 12240, 32767}, { 12786, 32767}, { 13356, 32767}, { 13953, 32767},
140  { 14576, 32767}, { 15226, 32767}, { 15906, 32767}, { 16615, 32767}
141 };
142 
143 static const struct {
144  const int16_t *tab1; const int16_t *tab2; int stride;
145 } tabs[] = {
146  {MACEtab1, &MACEtab2[0][0], 4},
147  {MACEtab3, &MACEtab4[0][0], 2},
148  {MACEtab1, &MACEtab2[0][0], 4}
149 };
150 
151 #define QT_8S_2_16S(x) (((x) & 0xFF00) | (((x) >> 8) & 0xFF))
152 
153 typedef struct ChannelData {
154  int16_t index, factor, prev2, previous, level;
155 } ChannelData;
156 
157 typedef struct MACEContext {
158  ChannelData chd[2];
159 } MACEContext;
160 
161 /**
162  * MACE version of av_clip_int16(). We have to do this to keep binary
163  * identical output to the binary decoder.
164  */
165 static inline int16_t mace_broken_clip_int16(int n)
166 {
167  if (n > 32767)
168  return 32767;
169  else if (n < -32768)
170  return -32767;
171  else
172  return n;
173 }
174 
175 static int16_t read_table(ChannelData *chd, uint8_t val, int tab_idx)
176 {
177  int16_t current;
178 
179  if (val < tabs[tab_idx].stride)
180  current = tabs[tab_idx].tab2[((chd->index & 0x7f0) >> 4) * tabs[tab_idx].stride + val];
181  else
182  current = - 1 - tabs[tab_idx].tab2[((chd->index & 0x7f0) >> 4)*tabs[tab_idx].stride + 2*tabs[tab_idx].stride-val-1];
183 
184  if (( chd->index += tabs[tab_idx].tab1[val]-(chd->index >> 5) ) < 0)
185  chd->index = 0;
186 
187  return current;
188 }
189 
190 static void chomp3(ChannelData *chd, int16_t *output, uint8_t val, int tab_idx)
191 {
192 
193  int16_t current = read_table(chd, val, tab_idx);
194 
195  current = mace_broken_clip_int16(current + chd->level);
196 
197  chd->level = current - (current >> 3);
198  *output = QT_8S_2_16S(current);
199 }
200 
201 static void chomp6(ChannelData *chd, int16_t *output, uint8_t val, int tab_idx)
202 {
203  int16_t current = read_table(chd, val, tab_idx);
204 
205  if ((chd->previous ^ current) >= 0) {
206  chd->factor = FFMIN(chd->factor + 506, 32767);
207  } else {
208  if (chd->factor - 314 < -32768)
209  chd->factor = -32767;
210  else
211  chd->factor -= 314;
212  }
213 
214  current = mace_broken_clip_int16(current + chd->level);
215 
216  chd->level = (current*chd->factor) >> 15;
217  current >>= 1;
218 
219  output[0] = QT_8S_2_16S(chd->previous + chd->prev2 -
220  ((chd->prev2-current) >> 2));
221  output[1] = QT_8S_2_16S(chd->previous + current +
222  ((chd->prev2-current) >> 2));
223  chd->prev2 = chd->previous;
224  chd->previous = current;
225 }
226 
227 static av_cold int mace_decode_init(AVCodecContext * avctx)
228 {
229  if (avctx->channels > 2 || avctx->channels < 1)
230  return AVERROR(EINVAL);
231  avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
232 
233  return 0;
234 }
235 
236 static int mace_decode_frame(AVCodecContext *avctx, void *data,
237  int *got_frame_ptr, AVPacket *avpkt)
238 {
239  AVFrame *frame = data;
240  const uint8_t *buf = avpkt->data;
241  int buf_size = avpkt->size;
242  int16_t **samples;
243  MACEContext *ctx = avctx->priv_data;
244  int i, j, k, l, ret;
245  int is_mace3 = (avctx->codec_id == AV_CODEC_ID_MACE3);
246 
247  if (buf_size % (avctx->channels << is_mace3)) {
248  av_log(avctx, AV_LOG_ERROR, "buffer size %d is odd\n", buf_size);
249  buf_size -= buf_size % (avctx->channels << is_mace3);
250  if (!buf_size)
251  return AVERROR_INVALIDDATA;
252  }
253 
254  /* get output buffer */
255  frame->nb_samples = 3 * (buf_size << (1 - is_mace3)) / avctx->channels;
256  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
257  return ret;
258  samples = (int16_t **)frame->extended_data;
259 
260  for(i = 0; i < avctx->channels; i++) {
261  int16_t *output = samples[i];
262 
263  for (j=0; j < buf_size / (avctx->channels << is_mace3); j++)
264  for (k=0; k < (1 << is_mace3); k++) {
265  uint8_t pkt = buf[(i << is_mace3) +
266  (j*avctx->channels << is_mace3) + k];
267 
268  uint8_t val[2][3] = {{pkt >> 5, (pkt >> 3) & 3, pkt & 7 },
269  {pkt & 7 , (pkt >> 3) & 3, pkt >> 5}};
270 
271  for (l=0; l < 3; l++) {
272  if (is_mace3)
273  chomp3(&ctx->chd[i], output, val[1][l], l);
274  else
275  chomp6(&ctx->chd[i], output, val[0][l], l);
276 
277  output += 1 << (1-is_mace3);
278  }
279  }
280  }
281 
282  *got_frame_ptr = 1;
283 
284  return buf_size;
285 }
286 
287 AVCodec ff_mace3_decoder = {
288  .name = "mace3",
289  .long_name = NULL_IF_CONFIG_SMALL("MACE (Macintosh Audio Compression/Expansion) 3:1"),
290  .type = AVMEDIA_TYPE_AUDIO,
291  .id = AV_CODEC_ID_MACE3,
292  .priv_data_size = sizeof(MACEContext),
293  .init = mace_decode_init,
294  .decode = mace_decode_frame,
295  .capabilities = CODEC_CAP_DR1,
296  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
297  AV_SAMPLE_FMT_NONE },
298 };
299 
300 AVCodec ff_mace6_decoder = {
301  .name = "mace6",
302  .long_name = NULL_IF_CONFIG_SMALL("MACE (Macintosh Audio Compression/Expansion) 6:1"),
303  .type = AVMEDIA_TYPE_AUDIO,
304  .id = AV_CODEC_ID_MACE6,
305  .priv_data_size = sizeof(MACEContext),
306  .init = mace_decode_init,
307  .decode = mace_decode_frame,
308  .capabilities = CODEC_CAP_DR1,
309  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
310  AV_SAMPLE_FMT_NONE },
311 };
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