1/* 2 * Copyright (c) 2012 Andrew D'Addesio 3 * Copyright (c) 2013-2014 Mozilla Corporation 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 * Opus decoder/parser shared code 25 */ 26 27#include <stdint.h> 28 29#include "libavutil/error.h" 30 31#include "opus.h" 32#include "vorbis.h" 33 34static const uint16_t opus_frame_duration[32] = { 35 480, 960, 1920, 2880, 36 480, 960, 1920, 2880, 37 480, 960, 1920, 2880, 38 480, 960, 39 480, 960, 40 120, 240, 480, 960, 41 120, 240, 480, 960, 42 120, 240, 480, 960, 43 120, 240, 480, 960, 44}; 45 46/** 47 * Read a 1- or 2-byte frame length 48 */ 49static inline int xiph_lacing_16bit(const uint8_t **ptr, const uint8_t *end) 50{ 51 int val; 52 53 if (*ptr >= end) 54 return AVERROR_INVALIDDATA; 55 val = *(*ptr)++; 56 if (val >= 252) { 57 if (*ptr >= end) 58 return AVERROR_INVALIDDATA; 59 val += 4 * *(*ptr)++; 60 } 61 return val; 62} 63 64/** 65 * Read a multi-byte length (used for code 3 packet padding size) 66 */ 67static inline int xiph_lacing_full(const uint8_t **ptr, const uint8_t *end) 68{ 69 int val = 0; 70 int next; 71 72 while (1) { 73 if (*ptr >= end || val > INT_MAX - 254) 74 return AVERROR_INVALIDDATA; 75 next = *(*ptr)++; 76 val += next; 77 if (next < 255) 78 break; 79 else 80 val--; 81 } 82 return val; 83} 84 85/** 86 * Parse Opus packet info from raw packet data 87 */ 88int ff_opus_parse_packet(OpusPacket *pkt, const uint8_t *buf, int buf_size, 89 int self_delimiting) 90{ 91 const uint8_t *ptr = buf; 92 const uint8_t *end = buf + buf_size; 93 int padding = 0; 94 int frame_bytes, i; 95 96 if (buf_size < 1) 97 goto fail; 98 99 /* TOC byte */ 100 i = *ptr++; 101 pkt->code = (i ) & 0x3; 102 pkt->stereo = (i >> 2) & 0x1; 103 pkt->config = (i >> 3) & 0x1F; 104 105 /* code 2 and code 3 packets have at least 1 byte after the TOC */ 106 if (pkt->code >= 2 && buf_size < 2) 107 goto fail; 108 109 switch (pkt->code) { 110 case 0: 111 /* 1 frame */ 112 pkt->frame_count = 1; 113 pkt->vbr = 0; 114 115 if (self_delimiting) { 116 int len = xiph_lacing_16bit(&ptr, end); 117 if (len < 0 || len > end - ptr) 118 goto fail; 119 end = ptr + len; 120 buf_size = end - buf; 121 } 122 123 frame_bytes = end - ptr; 124 if (frame_bytes > MAX_FRAME_SIZE) 125 goto fail; 126 pkt->frame_offset[0] = ptr - buf; 127 pkt->frame_size[0] = frame_bytes; 128 break; 129 case 1: 130 /* 2 frames, equal size */ 131 pkt->frame_count = 2; 132 pkt->vbr = 0; 133 134 if (self_delimiting) { 135 int len = xiph_lacing_16bit(&ptr, end); 136 if (len < 0 || 2 * len > end - ptr) 137 goto fail; 138 end = ptr + 2 * len; 139 buf_size = end - buf; 140 } 141 142 frame_bytes = end - ptr; 143 if (frame_bytes & 1 || frame_bytes >> 1 > MAX_FRAME_SIZE) 144 goto fail; 145 pkt->frame_offset[0] = ptr - buf; 146 pkt->frame_size[0] = frame_bytes >> 1; 147 pkt->frame_offset[1] = pkt->frame_offset[0] + pkt->frame_size[0]; 148 pkt->frame_size[1] = frame_bytes >> 1; 149 break; 150 case 2: 151 /* 2 frames, different sizes */ 152 pkt->frame_count = 2; 153 pkt->vbr = 1; 154 155 /* read 1st frame size */ 156 frame_bytes = xiph_lacing_16bit(&ptr, end); 157 if (frame_bytes < 0) 158 goto fail; 159 160 if (self_delimiting) { 161 int len = xiph_lacing_16bit(&ptr, end); 162 if (len < 0 || len + frame_bytes > end - ptr) 163 goto fail; 164 end = ptr + frame_bytes + len; 165 buf_size = end - buf; 166 } 167 168 pkt->frame_offset[0] = ptr - buf; 169 pkt->frame_size[0] = frame_bytes; 170 171 /* calculate 2nd frame size */ 172 frame_bytes = end - ptr - pkt->frame_size[0]; 173 if (frame_bytes < 0 || frame_bytes > MAX_FRAME_SIZE) 174 goto fail; 175 pkt->frame_offset[1] = pkt->frame_offset[0] + pkt->frame_size[0]; 176 pkt->frame_size[1] = frame_bytes; 177 break; 178 case 3: 179 /* 1 to 48 frames, can be different sizes */ 180 i = *ptr++; 181 pkt->frame_count = (i ) & 0x3F; 182 padding = (i >> 6) & 0x01; 183 pkt->vbr = (i >> 7) & 0x01; 184 185 if (pkt->frame_count == 0 || pkt->frame_count > MAX_FRAMES) 186 goto fail; 187 188 /* read padding size */ 189 if (padding) { 190 padding = xiph_lacing_full(&ptr, end); 191 if (padding < 0) 192 goto fail; 193 } 194 195 /* read frame sizes */ 196 if (pkt->vbr) { 197 /* for VBR, all frames except the final one have their size coded 198 in the bitstream. the last frame size is implicit. */ 199 int total_bytes = 0; 200 for (i = 0; i < pkt->frame_count - 1; i++) { 201 frame_bytes = xiph_lacing_16bit(&ptr, end); 202 if (frame_bytes < 0) 203 goto fail; 204 pkt->frame_size[i] = frame_bytes; 205 total_bytes += frame_bytes; 206 } 207 208 if (self_delimiting) { 209 int len = xiph_lacing_16bit(&ptr, end); 210 if (len < 0 || len + total_bytes + padding > end - ptr) 211 goto fail; 212 end = ptr + total_bytes + len + padding; 213 buf_size = end - buf; 214 } 215 216 frame_bytes = end - ptr - padding; 217 if (total_bytes > frame_bytes) 218 goto fail; 219 pkt->frame_offset[0] = ptr - buf; 220 for (i = 1; i < pkt->frame_count; i++) 221 pkt->frame_offset[i] = pkt->frame_offset[i-1] + pkt->frame_size[i-1]; 222 pkt->frame_size[pkt->frame_count-1] = frame_bytes - total_bytes; 223 } else { 224 /* for CBR, the remaining packet bytes are divided evenly between 225 the frames */ 226 if (self_delimiting) { 227 frame_bytes = xiph_lacing_16bit(&ptr, end); 228 if (frame_bytes < 0 || pkt->frame_count * frame_bytes + padding > end - ptr) 229 goto fail; 230 end = ptr + pkt->frame_count * frame_bytes + padding; 231 buf_size = end - buf; 232 } else { 233 frame_bytes = end - ptr - padding; 234 if (frame_bytes % pkt->frame_count || 235 frame_bytes / pkt->frame_count > MAX_FRAME_SIZE) 236 goto fail; 237 frame_bytes /= pkt->frame_count; 238 } 239 240 pkt->frame_offset[0] = ptr - buf; 241 pkt->frame_size[0] = frame_bytes; 242 for (i = 1; i < pkt->frame_count; i++) { 243 pkt->frame_offset[i] = pkt->frame_offset[i-1] + pkt->frame_size[i-1]; 244 pkt->frame_size[i] = frame_bytes; 245 } 246 } 247 } 248 249 pkt->packet_size = buf_size; 250 pkt->data_size = pkt->packet_size - padding; 251 252 /* total packet duration cannot be larger than 120ms */ 253 pkt->frame_duration = opus_frame_duration[pkt->config]; 254 if (pkt->frame_duration * pkt->frame_count > MAX_PACKET_DUR) 255 goto fail; 256 257 /* set mode and bandwidth */ 258 if (pkt->config < 12) { 259 pkt->mode = OPUS_MODE_SILK; 260 pkt->bandwidth = pkt->config >> 2; 261 } else if (pkt->config < 16) { 262 pkt->mode = OPUS_MODE_HYBRID; 263 pkt->bandwidth = OPUS_BANDWIDTH_SUPERWIDEBAND + (pkt->config >= 14); 264 } else { 265 pkt->mode = OPUS_MODE_CELT; 266 pkt->bandwidth = (pkt->config - 16) >> 2; 267 /* skip mediumband */ 268 if (pkt->bandwidth) 269 pkt->bandwidth++; 270 } 271 272 return 0; 273 274fail: 275 memset(pkt, 0, sizeof(*pkt)); 276 return AVERROR_INVALIDDATA; 277} 278 279static int channel_reorder_vorbis(int nb_channels, int channel_idx) 280{ 281 return ff_vorbis_channel_layout_offsets[nb_channels - 1][channel_idx]; 282} 283 284static int channel_reorder_unknown(int nb_channels, int channel_idx) 285{ 286 return channel_idx; 287} 288 289av_cold int ff_opus_parse_extradata(AVCodecContext *avctx, 290 OpusContext *s) 291{ 292 static const uint8_t default_channel_map[2] = { 0, 1 }; 293 uint8_t default_extradata[19] = { 294 'O', 'p', 'u', 's', 'H', 'e', 'a', 'd', 295 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 296 }; 297 298 int (*channel_reorder)(int, int) = channel_reorder_unknown; 299 300 const uint8_t *extradata, *channel_map; 301 int extradata_size; 302 int version, channels, map_type, streams, stereo_streams, i, j; 303 uint64_t layout; 304 305 if (!avctx->extradata) { 306 if (avctx->channels > 2) { 307 av_log(avctx, AV_LOG_ERROR, 308 "Multichannel configuration without extradata.\n"); 309 return AVERROR(EINVAL); 310 } 311 default_extradata[9] = (avctx->channels == 1) ? 1 : 2; 312 extradata = default_extradata; 313 extradata_size = sizeof(default_extradata); 314 } else { 315 extradata = avctx->extradata; 316 extradata_size = avctx->extradata_size; 317 } 318 319 if (extradata_size < 19) { 320 av_log(avctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", 321 extradata_size); 322 return AVERROR_INVALIDDATA; 323 } 324 325 version = extradata[8]; 326 if (version > 15) { 327 avpriv_request_sample(avctx, "Extradata version %d", version); 328 return AVERROR_PATCHWELCOME; 329 } 330 331 avctx->delay = AV_RL16(extradata + 10); 332 333 channels = extradata[9]; 334 if (!channels) { 335 av_log(avctx, AV_LOG_ERROR, "Zero channel count specified in the extadata\n"); 336 return AVERROR_INVALIDDATA; 337 } 338 339 s->gain_i = AV_RL16(extradata + 16); 340 if (s->gain_i) 341 s->gain = pow(10, s->gain_i / (20.0 * 256)); 342 343 map_type = extradata[18]; 344 if (!map_type) { 345 if (channels > 2) { 346 av_log(avctx, AV_LOG_ERROR, 347 "Channel mapping 0 is only specified for up to 2 channels\n"); 348 return AVERROR_INVALIDDATA; 349 } 350 layout = (channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO; 351 streams = 1; 352 stereo_streams = channels - 1; 353 channel_map = default_channel_map; 354 } else if (map_type == 1 || map_type == 255) { 355 if (extradata_size < 21 + channels) { 356 av_log(avctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", 357 extradata_size); 358 return AVERROR_INVALIDDATA; 359 } 360 361 streams = extradata[19]; 362 stereo_streams = extradata[20]; 363 if (!streams || stereo_streams > streams || 364 streams + stereo_streams > 255) { 365 av_log(avctx, AV_LOG_ERROR, 366 "Invalid stream/stereo stream count: %d/%d\n", streams, stereo_streams); 367 return AVERROR_INVALIDDATA; 368 } 369 370 if (map_type == 1) { 371 if (channels > 8) { 372 av_log(avctx, AV_LOG_ERROR, 373 "Channel mapping 1 is only specified for up to 8 channels\n"); 374 return AVERROR_INVALIDDATA; 375 } 376 layout = ff_vorbis_channel_layouts[channels - 1]; 377 channel_reorder = channel_reorder_vorbis; 378 } else 379 layout = 0; 380 381 channel_map = extradata + 21; 382 } else { 383 avpriv_request_sample(avctx, "Mapping type %d", map_type); 384 return AVERROR_PATCHWELCOME; 385 } 386 387 s->channel_maps = av_mallocz_array(channels, sizeof(*s->channel_maps)); 388 if (!s->channel_maps) 389 return AVERROR(ENOMEM); 390 391 for (i = 0; i < channels; i++) { 392 ChannelMap *map = &s->channel_maps[i]; 393 uint8_t idx = channel_map[channel_reorder(channels, i)]; 394 395 if (idx == 255) { 396 map->silence = 1; 397 continue; 398 } else if (idx >= streams + stereo_streams) { 399 av_log(avctx, AV_LOG_ERROR, 400 "Invalid channel map for output channel %d: %d\n", i, idx); 401 return AVERROR_INVALIDDATA; 402 } 403 404 /* check that we din't see this index yet */ 405 map->copy = 0; 406 for (j = 0; j < i; j++) 407 if (channel_map[channel_reorder(channels, j)] == idx) { 408 map->copy = 1; 409 map->copy_idx = j; 410 break; 411 } 412 413 if (idx < 2 * stereo_streams) { 414 map->stream_idx = idx / 2; 415 map->channel_idx = idx & 1; 416 } else { 417 map->stream_idx = idx - stereo_streams; 418 map->channel_idx = 0; 419 } 420 } 421 422 avctx->channels = channels; 423 avctx->channel_layout = layout; 424 s->nb_streams = streams; 425 s->nb_stereo_streams = stereo_streams; 426 427 return 0; 428} 429