FFmpeg: libavcodec/tta.c Source File

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tta.c

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1 /*

2 * TTA (The Lossless True Audio) decoder

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 */

22 /**

23 * @file

24 * TTA (The Lossless True Audio) decoder

25 * @see http://www.true-audio.com/

26 * @see http://tta.corecodec.org/

27 * @author Alex Beregszaszi

28 */

30 #define BITSTREAM_READER_LE

31 #include <limits.h>

32 #include "ttadata.h"

33 #include "avcodec.h"

34 #include "get_bits.h"

35 #include "thread.h"

36 #include "unary.h"

37 #include "internal.h"

38 #include "libavutil/crc.h"

39 #include "libavutil/intreadwrite.h"

40 #include "libavutil/opt.h"

42 #define FORMAT_SIMPLE 1

43 #define FORMAT_ENCRYPTED 2

45 typedef struct TTAContext {

46 AVClass *class;

47 AVCodecContext *avctx;

48 const AVCRC *crc_table;

50 int format, channels, bps;

51 unsigned data_length;

52 int frame_length, last_frame_length;

54 int32_t *decode_buffer;

56 uint8_t crc_pass[8];

57 uint8_t *pass;

58 TTAChannel *ch_ctx;

59 } TTAContext;

61 static inline void ttafilter_process(TTAFilter *c, int32_t *in)

62 {

63 register int32_t *dl = c->dl, *qm = c->qm, *dx = c->dx, sum = c->round;

65 if (c->error < 0) {

66 qm[0] -= dx[0]; qm[1] -= dx[1]; qm[2] -= dx[2]; qm[3] -= dx[3];

67 qm[4] -= dx[4]; qm[5] -= dx[5]; qm[6] -= dx[6]; qm[7] -= dx[7];

68 } else if (c->error > 0) {

69 qm[0] += dx[0]; qm[1] += dx[1]; qm[2] += dx[2]; qm[3] += dx[3];

70 qm[4] += dx[4]; qm[5] += dx[5]; qm[6] += dx[6]; qm[7] += dx[7];

71 }

73 sum += dl[0] * qm[0] + dl[1] * qm[1] + dl[2] * qm[2] + dl[3] * qm[3] +

74 dl[4] * qm[4] + dl[5] * qm[5] + dl[6] * qm[6] + dl[7] * qm[7];

76 dx[0] = dx[1]; dx[1] = dx[2]; dx[2] = dx[3]; dx[3] = dx[4];

77 dl[0] = dl[1]; dl[1] = dl[2]; dl[2] = dl[3]; dl[3] = dl[4];

79 dx[4] = ((dl[4] >> 30) | 1);

80 dx[5] = ((dl[5] >> 30) | 2) & ~1;

81 dx[6] = ((dl[6] >> 30) | 2) & ~1;

82 dx[7] = ((dl[7] >> 30) | 4) & ~3;

84 c->error = *in;

85 *in += (sum >> c->shift);

87 dl[4] = -dl[5]; dl[5] = -dl[6];

88 dl[6] = *in - dl[7]; dl[7] = *in;

89 dl[5] += dl[6]; dl[4] += dl[5];

90 }

92 static const int64_t tta_channel_layouts[7] = {

93 AV_CH_LAYOUT_STEREO,

94 AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY,

95 AV_CH_LAYOUT_QUAD,

96 0,

97 AV_CH_LAYOUT_5POINT1_BACK,

98 AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER,

99 AV_CH_LAYOUT_7POINT1_WIDE

100 };

101

102 static int tta_check_crc(TTAContext *s, const uint8_t *buf, int buf_size)

103 {

104 uint32_t crc, CRC;

105

106 CRC = AV_RL32(buf + buf_size);

107 crc = av_crc(s->crc_table, 0xFFFFFFFFU, buf, buf_size);

108 if (CRC != (crc ^ 0xFFFFFFFFU)) {

109 av_log(s->avctx, AV_LOG_ERROR, "CRC error\n");

110 return AVERROR_INVALIDDATA;

111 }

112

113 return 0;

114 }

115

116 static uint64_t tta_check_crc64(uint8_t *pass)

117 {

118 uint64_t crc = UINT64_MAX, poly = 0x42F0E1EBA9EA3693U;

119 uint8_t *end = pass + strlen(pass);

120 int i;

121

122 while (pass < end) {

123 crc ^= (uint64_t)*pass++ << 56;

124 for (i = 0; i < 8; i++)

125 crc = (crc << 1) ^ (poly & (((int64_t) crc) >> 63));

126 }

127

128 return crc ^ UINT64_MAX;

129 }

130

131 static int allocate_buffers(AVCodecContext *avctx)

132 {

133 TTAContext *s = avctx->priv_data;

134

135 if (s->bps < 3) {

136 s->decode_buffer = av_mallocz(sizeof(int32_t)*s->frame_length*s->channels);

137 if (!s->decode_buffer)

138 return AVERROR(ENOMEM);

139 } else

140 s->decode_buffer = NULL;

141 s->ch_ctx = av_malloc(avctx->channels * sizeof(*s->ch_ctx));

142 if (!s->ch_ctx) {

143 av_freep(&s->decode_buffer);

144 return AVERROR(ENOMEM);

145 }

146

147 return 0;

148 }

149

150 static av_cold int tta_decode_init(AVCodecContext * avctx)

151 {

152 TTAContext *s = avctx->priv_data;

153 GetBitContext gb;

154 int total_frames;

155

156 s->avctx = avctx;

157

158 // 30bytes includes TTA1 header

159 if (avctx->extradata_size < 22)

160 return AVERROR_INVALIDDATA;

161

162 s->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE);

163 init_get_bits(&gb, avctx->extradata, avctx->extradata_size * 8);

164 if (show_bits_long(&gb, 32) == AV_RL32("TTA1")) {

165 /* signature */

166 skip_bits_long(&gb, 32);

167

168 s->format = get_bits(&gb, 16);

169 if (s->format > 2) {

170 av_log(avctx, AV_LOG_ERROR, "Invalid format\n");

171 return AVERROR_INVALIDDATA;

172 }

173 if (s->format == FORMAT_ENCRYPTED) {

174 if (!s->pass) {

175 av_log(avctx, AV_LOG_ERROR, "Missing password for encrypted stream. Please use the -password option\n");

176 return AVERROR(EINVAL);

177 }

178 AV_WL64(s->crc_pass, tta_check_crc64(s->pass));

179 }

180 avctx->channels = s->channels = get_bits(&gb, 16);

181 if (s->channels > 1 && s->channels < 9)

182 avctx->channel_layout = tta_channel_layouts[s->channels-2];

183 avctx->bits_per_raw_sample = get_bits(&gb, 16);

184 s->bps = (avctx->bits_per_raw_sample + 7) / 8;

185 avctx->sample_rate = get_bits_long(&gb, 32);

186 s->data_length = get_bits_long(&gb, 32);

187 skip_bits_long(&gb, 32); // CRC32 of header

188

189 if (s->channels == 0) {

190 av_log(avctx, AV_LOG_ERROR, "Invalid number of channels\n");

191 return AVERROR_INVALIDDATA;

192 } else if (avctx->sample_rate == 0) {

193 av_log(avctx, AV_LOG_ERROR, "Invalid samplerate\n");

194 return AVERROR_INVALIDDATA;

195 }

196

197 switch(s->bps) {

198 case 1: avctx->sample_fmt = AV_SAMPLE_FMT_U8; break;

199 case 2:

200 avctx->sample_fmt = AV_SAMPLE_FMT_S16;

201 break;

202 case 3:

203 avctx->sample_fmt = AV_SAMPLE_FMT_S32;

204 break;

205 //case 4: avctx->sample_fmt = AV_SAMPLE_FMT_S32; break;

206 default:

207 av_log(avctx, AV_LOG_ERROR, "Invalid/unsupported sample format.\n");

208 return AVERROR_INVALIDDATA;

209 }

210

211 // prevent overflow

212 if (avctx->sample_rate > 0x7FFFFFu) {

213 av_log(avctx, AV_LOG_ERROR, "sample_rate too large\n");

214 return AVERROR(EINVAL);

215 }

216 s->frame_length = 256 * avctx->sample_rate / 245;

217

218 s->last_frame_length = s->data_length % s->frame_length;

219 total_frames = s->data_length / s->frame_length +

220 (s->last_frame_length ? 1 : 0);

221

222 av_log(avctx, AV_LOG_DEBUG, "format: %d chans: %d bps: %d rate: %d block: %d\n",

223 s->format, avctx->channels, avctx->bits_per_coded_sample, avctx->sample_rate,

224 avctx->block_align);

225 av_log(avctx, AV_LOG_DEBUG, "data_length: %d frame_length: %d last: %d total: %d\n",

226 s->data_length, s->frame_length, s->last_frame_length, total_frames);

227

228 if(s->frame_length >= UINT_MAX / (s->channels * sizeof(int32_t))){

229 av_log(avctx, AV_LOG_ERROR, "frame_length too large\n");

230 return AVERROR_INVALIDDATA;

231 }

232 } else {

233 av_log(avctx, AV_LOG_ERROR, "Wrong extradata present\n");

234 return AVERROR_INVALIDDATA;

235 }

236

237 return allocate_buffers(avctx);

238 }

239

240 static int tta_decode_frame(AVCodecContext *avctx, void *data,

241 int *got_frame_ptr, AVPacket *avpkt)

242 {

243 AVFrame *frame = data;

244 ThreadFrame tframe = { .f = data };

245 const uint8_t *buf = avpkt->data;

246 int buf_size = avpkt->size;

247 TTAContext *s = avctx->priv_data;

248 GetBitContext gb;

249 int i, ret;

250 int cur_chan = 0, framelen = s->frame_length;

251 int32_t *p;

252

253 if (avctx->err_recognition & AV_EF_CRCCHECK) {

254 if (buf_size < 4 || tta_check_crc(s, buf, buf_size - 4))

255 return AVERROR_INVALIDDATA;

256 }

257

258 if ((ret = init_get_bits8(&gb, avpkt->data, avpkt->size)) < 0)

259 return ret;

260

261 /* get output buffer */

262 frame->nb_samples = framelen;

263 if ((ret = ff_thread_get_buffer(avctx, &tframe, 0)) < 0)

264 return ret;

265

266 // decode directly to output buffer for 24-bit sample format

267 if (s->bps == 3)

268 s->decode_buffer = (int32_t *)frame->data[0];

269

270 // init per channel states

271 for (i = 0; i < s->channels; i++) {

272 TTAFilter *filter = &s->ch_ctx[i].filter;

273 s->ch_ctx[i].predictor = 0;

274 ff_tta_filter_init(filter, ff_tta_filter_configs[s->bps-1]);

275 if (s->format == FORMAT_ENCRYPTED) {

276 int i;

277 for (i = 0; i < 8; i++)

278 filter->qm[i] = sign_extend(s->crc_pass[i], 8);

279 }

280 ff_tta_rice_init(&s->ch_ctx[i].rice, 10, 10);

281 }

282

283 i = 0;

284 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) {

285 int32_t *predictor = &s->ch_ctx[cur_chan].predictor;

286 TTAFilter *filter = &s->ch_ctx[cur_chan].filter;

287 TTARice *rice = &s->ch_ctx[cur_chan].rice;

288 uint32_t unary, depth, k;

289 int32_t value;

290

291 unary = get_unary(&gb, 0, get_bits_left(&gb));

292

293 if (unary == 0) {

294 depth = 0;

295 k = rice->k0;

296 } else {

297 depth = 1;

298 k = rice->k1;

299 unary--;

300 }

301

302 if (get_bits_left(&gb) < k) {

303 ret = AVERROR_INVALIDDATA;

304 goto error;

305 }

306

307 if (k) {

308 if (k > MIN_CACHE_BITS) {

309 ret = AVERROR_INVALIDDATA;

310 goto error;

311 }

312 value = (unary << k) + get_bits(&gb, k);

313 } else

314 value = unary;

315

316 // FIXME: copy paste from original

317 switch (depth) {

318 case 1:

319 rice->sum1 += value - (rice->sum1 >> 4);

320 if (rice->k1 > 0 && rice->sum1 < ff_tta_shift_16[rice->k1])

321 rice->k1--;

322 else if(rice->sum1 > ff_tta_shift_16[rice->k1 + 1])

323 rice->k1++;

324 value += ff_tta_shift_1[rice->k0];

325 default:

326 rice->sum0 += value - (rice->sum0 >> 4);

327 if (rice->k0 > 0 && rice->sum0 < ff_tta_shift_16[rice->k0])

328 rice->k0--;

329 else if(rice->sum0 > ff_tta_shift_16[rice->k0 + 1])

330 rice->k0++;

331 }

332

333 // extract coded value

334 *p = 1 + ((value >> 1) ^ ((value & 1) - 1));

335

336 // run hybrid filter

337 ttafilter_process(filter, p);

338

339 // fixed order prediction

340 #define PRED(x, k) (int32_t)((((uint64_t)x << k) - x) >> k)

341 switch (s->bps) {

342 case 1: *p += PRED(*predictor, 4); break;

343 case 2:

344 case 3: *p += PRED(*predictor, 5); break;

345 case 4: *p += *predictor; break;

346 }

347 *predictor = *p;

348

349 // flip channels

350 if (cur_chan < (s->channels-1))

351 cur_chan++;

352 else {

353 // decorrelate in case of multiple channels

354 if (s->channels > 1) {

355 int32_t *r = p - 1;

356 for (*p += *r / 2; r > p - s->channels; r--)

357 *r = *(r + 1) - *r;

358 }

359 cur_chan = 0;

360 i++;

361 // check for last frame

362 if (i == s->last_frame_length && get_bits_left(&gb) / 8 == 4) {

363 frame->nb_samples = framelen = s->last_frame_length;

364 break;

365 }

366 }

367 }

368

369 align_get_bits(&gb);

370 if (get_bits_left(&gb) < 32) {

371 ret = AVERROR_INVALIDDATA;

372 goto error;

373 }

374 skip_bits_long(&gb, 32); // frame crc

375

376 // convert to output buffer

377 switch (s->bps) {

378 case 1: {

379 uint8_t *samples = (uint8_t *)frame->data[0];

380 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)

381 *samples++ = *p + 0x80;

382 break;

383 }

384 case 2: {

385 int16_t *samples = (int16_t *)frame->data[0];

386 for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++)

387 *samples++ = *p;

388 break;

389 }

390 case 3: {

391 // shift samples for 24-bit sample format

392 int32_t *samples = (int32_t *)frame->data[0];

393 for (i = 0; i < framelen * s->channels; i++)

394 *samples++ <<= 8;

395 // reset decode buffer

396 s->decode_buffer = NULL;

397 break;

398 }

399 }

400

401 *got_frame_ptr = 1;

402

403 return buf_size;

404 error:

405 // reset decode buffer

406 if (s->bps == 3)

407 s->decode_buffer = NULL;

408 return ret;

409 }

410

411 static int init_thread_copy(AVCodecContext *avctx)

412 {

413 TTAContext *s = avctx->priv_data;

414 s->avctx = avctx;

415 return allocate_buffers(avctx);

416 }

417

418 static av_cold int tta_decode_close(AVCodecContext *avctx) {

419 TTAContext *s = avctx->priv_data;

420

421 if (s->bps < 3)

422 av_free(s->decode_buffer);

423 s->decode_buffer = NULL;

424 av_freep(&s->ch_ctx);

425

426 return 0;

427 }

428

429 #define OFFSET(x) offsetof(TTAContext, x)

430 #define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_AUDIO_PARAM)

431 static const AVOption options[] = {

432 { "password", "Set decoding password", OFFSET(pass), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, DEC },

433 { NULL },

434 };

435

436 static const AVClass tta_decoder_class = {

437 .class_name = "TTA Decoder",

438 .item_name = av_default_item_name,

439 .option = options,

440 .version = LIBAVUTIL_VERSION_INT,

441 };

442

443 AVCodec ff_tta_decoder = {

444 .name = "tta",

445 .type = AVMEDIA_TYPE_AUDIO,

446 .id = AV_CODEC_ID_TTA,

447 .priv_data_size = sizeof(TTAContext),

448 .init = tta_decode_init,

449 .close = tta_decode_close,

450 .decode = tta_decode_frame,

451 .init_thread_copy = ONLY_IF_THREADS_ENABLED(init_thread_copy),

452 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,

453 .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),

454 .priv_class = &tta_decoder_class,

455 };

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