FFmpeg: libavcodec/ratecontrol.c Source File

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ratecontrol.c

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1 /*

2 * Rate control for video encoders

3 *

5 *

6 * This file is part of FFmpeg.

7 *

8 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software

20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

21 */

23 /**

24 * @file

25 * Rate control for video encoders.

26 */

28 #include "libavutil/attributes.h"

29 #include "avcodec.h"

30 #include "ratecontrol.h"

31 #include "mpegvideo.h"

32 #include "libavutil/eval.h"

34 #undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.

35 #include <assert.h>

37 #ifndef M_E

38 #define M_E 2.718281828

39 #endif

41 static int init_pass2(MpegEncContext *s);

42 static double get_qscale(MpegEncContext *s, RateControlEntry *rce,

43 double rate_factor, int frame_num);

45 void ff_write_pass1_stats(MpegEncContext *s)

46 {

47 snprintf(s->avctx->stats_out, 256,

48 "in:%d out:%d type:%d q:%d itex:%d ptex:%d mv:%d misc:%d "

49 "fcode:%d bcode:%d mc-var:%d var:%d icount:%d skipcount:%d hbits:%d;\n",

50 s->current_picture_ptr->f.display_picture_number,

51 s->current_picture_ptr->f.coded_picture_number,

52 s->pict_type,

53 s->current_picture.f.quality,

54 s->i_tex_bits,

55 s->p_tex_bits,

56 s->mv_bits,

57 s->misc_bits,

58 s->f_code,

59 s->b_code,

60 s->current_picture.mc_mb_var_sum,

61 s->current_picture.mb_var_sum,

62 s->i_count, s->skip_count,

63 s->header_bits);

64 }

66 static double get_fps(AVCodecContext *avctx)

67 {

68 return 1.0 / av_q2d(avctx->time_base) / FFMAX(avctx->ticks_per_frame, 1);

69 }

71 static inline double qp2bits(RateControlEntry *rce, double qp)

72 {

73 if (qp <= 0.0) {

74 av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");

75 }

76 return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / qp;

77 }

79 static inline double bits2qp(RateControlEntry *rce, double bits)

80 {

81 if (bits < 0.9) {

82 av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");

83 }

84 return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / bits;

85 }

87 av_cold int ff_rate_control_init(MpegEncContext *s)

88 {

89 RateControlContext *rcc = &s->rc_context;

90 int i, res;

91 static const char * const const_names[] = {

92 "PI",

93 "E",

94 "iTex",

95 "pTex",

96 "tex",

97 "mv",

98 "fCode",

99 "iCount",

100 "mcVar",

101 "var",

102 "isI",

103 "isP",

104 "isB",

105 "avgQP",

106 "qComp",

107 #if 0

108 "lastIQP",

109 "lastPQP",

110 "lastBQP",

111 "nextNonBQP",

112 #endif

113 "avgIITex",

114 "avgPITex",

115 "avgPPTex",

116 "avgBPTex",

117 "avgTex",

118 NULL

119 };

120 static double (* const func1[])(void *, double) = {

121 (void *)bits2qp,

122 (void *)qp2bits,

123 NULL

124 };

125 static const char * const func1_names[] = {

126 "bits2qp",

127 "qp2bits",

128 NULL

129 };

130 emms_c();

131

132 if (!s->avctx->rc_max_available_vbv_use && s->avctx->rc_buffer_size) {

133 if (s->avctx->rc_max_rate) {

134 s->avctx->rc_max_available_vbv_use = av_clipf(s->avctx->rc_max_rate/(s->avctx->rc_buffer_size*get_fps(s->avctx)), 1.0/3, 1.0);

135 } else

136 s->avctx->rc_max_available_vbv_use = 1.0;

137 }

138

139 res = av_expr_parse(&rcc->rc_eq_eval,

140 s->avctx->rc_eq ? s->avctx->rc_eq : "tex^qComp",

141 const_names, func1_names, func1,

142 NULL, NULL, 0, s->avctx);

143 if (res < 0) {

144 av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\"\n", s->avctx->rc_eq);

145 return res;

146 }

147

148 for (i = 0; i < 5; i++) {

149 rcc->pred[i].coeff = FF_QP2LAMBDA * 7.0;

150 rcc->pred[i].count = 1.0;

151 rcc->pred[i].decay = 0.4;

152

153 rcc->i_cplx_sum [i] =

154 rcc->p_cplx_sum [i] =

155 rcc->mv_bits_sum[i] =

156 rcc->qscale_sum [i] =

157 rcc->frame_count[i] = 1; // 1 is better because of 1/0 and such

158

159 rcc->last_qscale_for[i] = FF_QP2LAMBDA * 5;

160 }

161 rcc->buffer_index = s->avctx->rc_initial_buffer_occupancy;

162 if (!rcc->buffer_index)

163 rcc->buffer_index = s->avctx->rc_buffer_size * 3 / 4;

164

165 if (s->flags & CODEC_FLAG_PASS2) {

166 int i;

167 char *p;

168

169 /* find number of pics */

170 p = s->avctx->stats_in;

171 for (i = -1; p; i++)

172 p = strchr(p + 1, ';');

173 i += s->max_b_frames;

174 if (i <= 0 || i >= INT_MAX / sizeof(RateControlEntry))

175 return -1;

176 rcc->entry = av_mallocz(i * sizeof(RateControlEntry));

177 rcc->num_entries = i;

178

179 /* init all to skipped p frames

180 * (with b frames we might have a not encoded frame at the end FIXME) */

181 for (i = 0; i < rcc->num_entries; i++) {

182 RateControlEntry *rce = &rcc->entry[i];

183

184 rce->pict_type = rce->new_pict_type = AV_PICTURE_TYPE_P;

185 rce->qscale = rce->new_qscale = FF_QP2LAMBDA * 2;

186 rce->misc_bits = s->mb_num + 10;

187 rce->mb_var_sum = s->mb_num * 100;

188 }

189

190 /* read stats */

191 p = s->avctx->stats_in;

192 for (i = 0; i < rcc->num_entries - s->max_b_frames; i++) {

193 RateControlEntry *rce;

194 int picture_number;

195 int e;

196 char *next;

197

198 next = strchr(p, ';');

199 if (next) {

200 (*next) = 0; // sscanf in unbelievably slow on looong strings // FIXME copy / do not write

201 next++;

202 }

203 e = sscanf(p, " in:%d ", &picture_number);

204

205 assert(picture_number >= 0);

206 assert(picture_number < rcc->num_entries);

207 rce = &rcc->entry[picture_number];

208

209 e += sscanf(p, " in:%*d out:%*d type:%d q:%f itex:%d ptex:%d mv:%d misc:%d fcode:%d bcode:%d mc-var:%d var:%d icount:%d skipcount:%d hbits:%d",

210 &rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits,

211 &rce->mv_bits, &rce->misc_bits,

212 &rce->f_code, &rce->b_code,

213 &rce->mc_mb_var_sum, &rce->mb_var_sum,

214 &rce->i_count, &rce->skip_count, &rce->header_bits);

215 if (e != 14) {

216 av_log(s->avctx, AV_LOG_ERROR,

217 "statistics are damaged at line %d, parser out=%d\n",

218 i, e);

219 return -1;

220 }

221

222 p = next;

223 }

224

225 if (init_pass2(s) < 0)

226 return -1;

227

228 // FIXME maybe move to end

229 if ((s->flags & CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {

230 #if CONFIG_LIBXVID

231 return ff_xvid_rate_control_init(s);

232 #else

233 av_log(s->avctx, AV_LOG_ERROR,

234 "Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");

235 return -1;

236 #endif

237 }

238 }

239

240 if (!(s->flags & CODEC_FLAG_PASS2)) {

241 rcc->short_term_qsum = 0.001;

242 rcc->short_term_qcount = 0.001;

243

244 rcc->pass1_rc_eq_output_sum = 0.001;

245 rcc->pass1_wanted_bits = 0.001;

246

247 if (s->avctx->qblur > 1.0) {

248 av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");

249 return -1;

250 }

251 /* init stuff with the user specified complexity */

252 if (s->avctx->rc_initial_cplx) {

253 for (i = 0; i < 60 * 30; i++) {

254 double bits = s->avctx->rc_initial_cplx * (i / 10000.0 + 1.0) * s->mb_num;

255 RateControlEntry rce;

256

257 if (i % ((s->gop_size + 3) / 4) == 0)

258 rce.pict_type = AV_PICTURE_TYPE_I;

259 else if (i % (s->max_b_frames + 1))

260 rce.pict_type = AV_PICTURE_TYPE_B;

261 else

262 rce.pict_type = AV_PICTURE_TYPE_P;

263

264 rce.new_pict_type = rce.pict_type;

265 rce.mc_mb_var_sum = bits * s->mb_num / 100000;

266 rce.mb_var_sum = s->mb_num;

267

268 rce.qscale = FF_QP2LAMBDA * 2;

269 rce.f_code = 2;

270 rce.b_code = 1;

271 rce.misc_bits = 1;

272

273 if (s->pict_type == AV_PICTURE_TYPE_I) {

274 rce.i_count = s->mb_num;

275 rce.i_tex_bits = bits;

276 rce.p_tex_bits = 0;

277 rce.mv_bits = 0;

278 } else {

279 rce.i_count = 0; // FIXME we do know this approx

280 rce.i_tex_bits = 0;

281 rce.p_tex_bits = bits * 0.9;

282 rce.mv_bits = bits * 0.1;

283 }

284 rcc->i_cplx_sum[rce.pict_type] += rce.i_tex_bits * rce.qscale;

285 rcc->p_cplx_sum[rce.pict_type] += rce.p_tex_bits * rce.qscale;

286 rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;

287 rcc->frame_count[rce.pict_type]++;

288

289 get_qscale(s, &rce, rcc->pass1_wanted_bits / rcc->pass1_rc_eq_output_sum, i);

290

291 // FIXME misbehaves a little for variable fps

292 rcc->pass1_wanted_bits += s->bit_rate / get_fps(s->avctx);

293 }

294 }

295 }

296

297 return 0;

298 }

299

300 av_cold void ff_rate_control_uninit(MpegEncContext *s)

301 {

302 RateControlContext *rcc = &s->rc_context;

303 emms_c();

304

305 av_expr_free(rcc->rc_eq_eval);

306 av_freep(&rcc->entry);

307

308 #if CONFIG_LIBXVID

309 if ((s->flags & CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)

310 ff_xvid_rate_control_uninit(s);

311 #endif

312 }

313

314 int ff_vbv_update(MpegEncContext *s, int frame_size)

315 {

316 RateControlContext *rcc = &s->rc_context;

317 const double fps = get_fps(s->avctx);

318 const int buffer_size = s->avctx->rc_buffer_size;

319 const double min_rate = s->avctx->rc_min_rate / fps;

320 const double max_rate = s->avctx->rc_max_rate / fps;

321

322 av_dlog(s, "%d %f %d %f %f\n",

323 buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);

324

325 if (buffer_size) {

326 int left;

327

328 rcc->buffer_index -= frame_size;

329 if (rcc->buffer_index < 0) {

330 av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");

331 rcc->buffer_index = 0;

332 }

333

334 left = buffer_size - rcc->buffer_index - 1;

335 rcc->buffer_index += av_clip(left, min_rate, max_rate);

336

337 if (rcc->buffer_index > buffer_size) {

338 int stuffing = ceil((rcc->buffer_index - buffer_size) / 8);

339

340 if (stuffing < 4 && s->codec_id == AV_CODEC_ID_MPEG4)

341 stuffing = 4;

342 rcc->buffer_index -= 8 * stuffing;

343

344 if (s->avctx->debug & FF_DEBUG_RC)

345 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);

346

347 return stuffing;

348 }

349 }

350 return 0;

351 }

352

353 /**

354 * Modify the bitrate curve from pass1 for one frame.

355 */

356 static double get_qscale(MpegEncContext *s, RateControlEntry *rce,

357 double rate_factor, int frame_num)

358 {

359 RateControlContext *rcc = &s->rc_context;

360 AVCodecContext *a = s->avctx;

361 const int pict_type = rce->new_pict_type;

362 const double mb_num = s->mb_num;

363 double q, bits;

364 int i;

365

366 double const_values[] = {

367 M_PI,

368 M_E,

369 rce->i_tex_bits * rce->qscale,

370 rce->p_tex_bits * rce->qscale,

371 (rce->i_tex_bits + rce->p_tex_bits) * (double)rce->qscale,

372 rce->mv_bits / mb_num,

373 rce->pict_type == AV_PICTURE_TYPE_B ? (rce->f_code + rce->b_code) * 0.5 : rce->f_code,

374 rce->i_count / mb_num,

375 rce->mc_mb_var_sum / mb_num,

376 rce->mb_var_sum / mb_num,

377 rce->pict_type == AV_PICTURE_TYPE_I,

378 rce->pict_type == AV_PICTURE_TYPE_P,

379 rce->pict_type == AV_PICTURE_TYPE_B,

380 rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],

381 a->qcompress,

382 #if 0

383 rcc->last_qscale_for[AV_PICTURE_TYPE_I],

384 rcc->last_qscale_for[AV_PICTURE_TYPE_P],

385 rcc->last_qscale_for[AV_PICTURE_TYPE_B],

386 rcc->next_non_b_qscale,

387 #endif

388 rcc->i_cplx_sum[AV_PICTURE_TYPE_I] / (double)rcc->frame_count[AV_PICTURE_TYPE_I],

389 rcc->i_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],

390 rcc->p_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],

391 rcc->p_cplx_sum[AV_PICTURE_TYPE_B] / (double)rcc->frame_count[AV_PICTURE_TYPE_B],

392 (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],

393 0

394 };

395

396 bits = av_expr_eval(rcc->rc_eq_eval, const_values, rce);

397 if (isnan(bits)) {

398 av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);

399 return -1;

400 }

401

402 rcc->pass1_rc_eq_output_sum += bits;

403 bits *= rate_factor;

404 if (bits < 0.0)

405 bits = 0.0;

406 bits += 1.0; // avoid 1/0 issues

407

408 /* user override */

409 for (i = 0; i < s->avctx->rc_override_count; i++) {

410 RcOverride *rco = s->avctx->rc_override;

411 if (rco[i].start_frame > frame_num)

412 continue;

413 if (rco[i].end_frame < frame_num)

414 continue;

415

416 if (rco[i].qscale)

417 bits = qp2bits(rce, rco[i].qscale); // FIXME move at end to really force it?

418 else

419 bits *= rco[i].quality_factor;

420 }

421

422 q = bits2qp(rce, bits);

423

424 /* I/B difference */

425 if (pict_type == AV_PICTURE_TYPE_I && s->avctx->i_quant_factor < 0.0)

426 q = -q * s->avctx->i_quant_factor + s->avctx->i_quant_offset;

427 else if (pict_type == AV_PICTURE_TYPE_B && s->avctx->b_quant_factor < 0.0)

428 q = -q * s->avctx->b_quant_factor + s->avctx->b_quant_offset;

429 if (q < 1)

430 q = 1;

431

432 return q;

433 }

434

435 static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q)

436 {

437 RateControlContext *rcc = &s->rc_context;

438 AVCodecContext *a = s->avctx;

439 const int pict_type = rce->new_pict_type;

440 const double last_p_q = rcc->last_qscale_for[AV_PICTURE_TYPE_P];

441 const double last_non_b_q = rcc->last_qscale_for[rcc->last_non_b_pict_type];

442

443 if (pict_type == AV_PICTURE_TYPE_I &&

444 (a->i_quant_factor > 0.0 || rcc->last_non_b_pict_type == AV_PICTURE_TYPE_P))

445 q = last_p_q * FFABS(a->i_quant_factor) + a->i_quant_offset;

446 else if (pict_type == AV_PICTURE_TYPE_B &&

447 a->b_quant_factor > 0.0)

448 q = last_non_b_q * a->b_quant_factor + a->b_quant_offset;

449 if (q < 1)

450 q = 1;

451

452 /* last qscale / qdiff stuff */

453 if (rcc->last_non_b_pict_type == pict_type || pict_type != AV_PICTURE_TYPE_I) {

454 double last_q = rcc->last_qscale_for[pict_type];

455 const int maxdiff = FF_QP2LAMBDA * a->max_qdiff;

456

457 if (q > last_q + maxdiff)

458 q = last_q + maxdiff;

459 else if (q < last_q - maxdiff)

460 q = last_q - maxdiff;

461 }

462

463 rcc->last_qscale_for[pict_type] = q; // Note we cannot do that after blurring

464

465 if (pict_type != AV_PICTURE_TYPE_B)

466 rcc->last_non_b_pict_type = pict_type;

467

468 return q;

469 }

470

471 /**

472 * Get the qmin & qmax for pict_type.

473 */

474 static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type)

475 {

476 int qmin = s->avctx->lmin;

477 int qmax = s->avctx->lmax;

478

479 assert(qmin <= qmax);

480

481 switch (pict_type) {

482 case AV_PICTURE_TYPE_B:

483 qmin = (int)(qmin * FFABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset + 0.5);

484 qmax = (int)(qmax * FFABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset + 0.5);

485 break;

486 case AV_PICTURE_TYPE_I:

487 qmin = (int)(qmin * FFABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset + 0.5);

488 qmax = (int)(qmax * FFABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset + 0.5);

489 break;

490 }

491

492 qmin = av_clip(qmin, 1, FF_LAMBDA_MAX);

493 qmax = av_clip(qmax, 1, FF_LAMBDA_MAX);

494

495 if (qmax < qmin)

496 qmax = qmin;

497

498 *qmin_ret = qmin;

499 *qmax_ret = qmax;

500 }

501

502 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce,

503 double q, int frame_num)

504 {

505 RateControlContext *rcc = &s->rc_context;

506 const double buffer_size = s->avctx->rc_buffer_size;

507 const double fps = get_fps(s->avctx);

508 const double min_rate = s->avctx->rc_min_rate / fps;

509 const double max_rate = s->avctx->rc_max_rate / fps;

510 const int pict_type = rce->new_pict_type;

511 int qmin, qmax;

512

513 get_qminmax(&qmin, &qmax, s, pict_type);

514

515 /* modulation */

516 if (s->avctx->rc_qmod_freq &&

517 frame_num % s->avctx->rc_qmod_freq == 0 &&

518 pict_type == AV_PICTURE_TYPE_P)

519 q *= s->avctx->rc_qmod_amp;

520

521 /* buffer overflow/underflow protection */

522 if (buffer_size) {

523 double expected_size = rcc->buffer_index;

524 double q_limit;

525

526 if (min_rate) {

527 double d = 2 * (buffer_size - expected_size) / buffer_size;

528 if (d > 1.0)

529 d = 1.0;

530 else if (d < 0.0001)

531 d = 0.0001;

532 q *= pow(d, 1.0 / s->avctx->rc_buffer_aggressivity);

533

534 q_limit = bits2qp(rce,

535 FFMAX((min_rate - buffer_size + rcc->buffer_index) *

536 s->avctx->rc_min_vbv_overflow_use, 1));

537

538 if (q > q_limit) {

539 if (s->avctx->debug & FF_DEBUG_RC)

540 av_log(s->avctx, AV_LOG_DEBUG,

541 "limiting QP %f -> %f\n", q, q_limit);

542 q = q_limit;

543 }

544 }

545

546 if (max_rate) {

547 double d = 2 * expected_size / buffer_size;

548 if (d > 1.0)

549 d = 1.0;

550 else if (d < 0.0001)

551 d = 0.0001;

552 q /= pow(d, 1.0 / s->avctx->rc_buffer_aggressivity);

553

554 q_limit = bits2qp(rce,

555 FFMAX(rcc->buffer_index *

556 s->avctx->rc_max_available_vbv_use,

557 1));

558 if (q < q_limit) {

559 if (s->avctx->debug & FF_DEBUG_RC)

560 av_log(s->avctx, AV_LOG_DEBUG,

561 "limiting QP %f -> %f\n", q, q_limit);

562 q = q_limit;

563 }

564 }

565 }

566 av_dlog(s, "q:%f max:%f min:%f size:%f index:%f agr:%f\n",

567 q, max_rate, min_rate, buffer_size, rcc->buffer_index,

568 s->avctx->rc_buffer_aggressivity);

569 if (s->avctx->rc_qsquish == 0.0 || qmin == qmax) {

570 if (q < qmin)

571 q = qmin;

572 else if (q > qmax)

573 q = qmax;

574 } else {

575 double min2 = log(qmin);

576 double max2 = log(qmax);

577

578 q = log(q);

579 q = (q - min2) / (max2 - min2) - 0.5;

580 q *= -4.0;

581 q = 1.0 / (1.0 + exp(q));

582 q = q * (max2 - min2) + min2;

583

584 q = exp(q);

585 }

586

587 return q;

588 }

589

590 // ----------------------------------

591 // 1 Pass Code

592

593 static double predict_size(Predictor *p, double q, double var)

594 {

595 return p->coeff * var / (q * p->count);

596 }

597

598 static void update_predictor(Predictor *p, double q, double var, double size)

599 {

600 double new_coeff = size * q / (var + 1);

601 if (var < 10)

602 return;

603

604 p->count *= p->decay;

605 p->coeff *= p->decay;

606 p->count++;

607 p->coeff += new_coeff;

608 }

609

610 static void adaptive_quantization(MpegEncContext *s, double q)

611 {

612 int i;

613 const float lumi_masking = s->avctx->lumi_masking / (128.0 * 128.0);

614 const float dark_masking = s->avctx->dark_masking / (128.0 * 128.0);

615 const float temp_cplx_masking = s->avctx->temporal_cplx_masking;

616 const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;

617 const float p_masking = s->avctx->p_masking;

618 const float border_masking = s->avctx->border_masking;

619 float bits_sum = 0.0;

620 float cplx_sum = 0.0;

621 float *cplx_tab = s->cplx_tab;

622 float *bits_tab = s->bits_tab;

623 const int qmin = s->avctx->mb_lmin;

624 const int qmax = s->avctx->mb_lmax;

625 Picture *const pic = &s->current_picture;

626 const int mb_width = s->mb_width;

627 const int mb_height = s->mb_height;

628

629 for (i = 0; i < s->mb_num; i++) {

630 const int mb_xy = s->mb_index2xy[i];

631 float temp_cplx = sqrt(pic->mc_mb_var[mb_xy]); // FIXME merge in pow()

632 float spat_cplx = sqrt(pic->mb_var[mb_xy]);

633 const int lumi = pic->mb_mean[mb_xy];

634 float bits, cplx, factor;

635 int mb_x = mb_xy % s->mb_stride;

636 int mb_y = mb_xy / s->mb_stride;

637 int mb_distance;

638 float mb_factor = 0.0;

639 if (spat_cplx < 4)

640 spat_cplx = 4; // FIXME finetune

641 if (temp_cplx < 4)

642 temp_cplx = 4; // FIXME finetune

643

644 if ((s->mb_type[mb_xy] & CANDIDATE_MB_TYPE_INTRA)) { // FIXME hq mode

645 cplx = spat_cplx;

646 factor = 1.0 + p_masking;

647 } else {

648 cplx = temp_cplx;

649 factor = pow(temp_cplx, -temp_cplx_masking);

650 }

651 factor *= pow(spat_cplx, -spatial_cplx_masking);

652

653 if (lumi > 127)

654 factor *= (1.0 - (lumi - 128) * (lumi - 128) * lumi_masking);

655 else

656 factor *= (1.0 - (lumi - 128) * (lumi - 128) * dark_masking);

657

658 if (mb_x < mb_width / 5) {

659 mb_distance = mb_width / 5 - mb_x;

660 mb_factor = (float)mb_distance / (float)(mb_width / 5);

661 } else if (mb_x > 4 * mb_width / 5) {

662 mb_distance = mb_x - 4 * mb_width / 5;

663 mb_factor = (float)mb_distance / (float)(mb_width / 5);

664 }

665 if (mb_y < mb_height / 5) {

666 mb_distance = mb_height / 5 - mb_y;

667 mb_factor = FFMAX(mb_factor,

668 (float)mb_distance / (float)(mb_height / 5));

669 } else if (mb_y > 4 * mb_height / 5) {

670 mb_distance = mb_y - 4 * mb_height / 5;

671 mb_factor = FFMAX(mb_factor,

672 (float)mb_distance / (float)(mb_height / 5));

673 }

674

675 factor *= 1.0 - border_masking * mb_factor;

676

677 if (factor < 0.00001)

678 factor = 0.00001;

679

680 bits = cplx * factor;

681 cplx_sum += cplx;

682 bits_sum += bits;

683 cplx_tab[i] = cplx;

684 bits_tab[i] = bits;

685 }

686

687 /* handle qmin/qmax clipping */

688 if (s->flags & CODEC_FLAG_NORMALIZE_AQP) {

689 float factor = bits_sum / cplx_sum;

690 for (i = 0; i < s->mb_num; i++) {

691 float newq = q * cplx_tab[i] / bits_tab[i];

692 newq *= factor;

693

694 if (newq > qmax) {

695 bits_sum -= bits_tab[i];

696 cplx_sum -= cplx_tab[i] * q / qmax;

697 } else if (newq < qmin) {

698 bits_sum -= bits_tab[i];

699 cplx_sum -= cplx_tab[i] * q / qmin;

700 }

701 }

702 if (bits_sum < 0.001)

703 bits_sum = 0.001;

704 if (cplx_sum < 0.001)

705 cplx_sum = 0.001;

706 }

707

708 for (i = 0; i < s->mb_num; i++) {

709 const int mb_xy = s->mb_index2xy[i];

710 float newq = q * cplx_tab[i] / bits_tab[i];

711 int intq;

712

713 if (s->flags & CODEC_FLAG_NORMALIZE_AQP) {

714 newq *= bits_sum / cplx_sum;

715 }

716

717 intq = (int)(newq + 0.5);

718

719 if (intq > qmax)

720 intq = qmax;

721 else if (intq < qmin)

722 intq = qmin;

723 s->lambda_table[mb_xy] = intq;

724 }

725 }

726

727 void ff_get_2pass_fcode(MpegEncContext *s)

728 {

729 RateControlContext *rcc = &s->rc_context;

730 RateControlEntry *rce = &rcc->entry[s->picture_number];

731

732 s->f_code = rce->f_code;

733 s->b_code = rce->b_code;

734 }

735

736 // FIXME rd or at least approx for dquant

737

738 float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)

739 {

740 float q;

741 int qmin, qmax;

742 float br_compensation;

743 double diff;

744 double short_term_q;

745 double fps;

746 int picture_number = s->picture_number;

747 int64_t wanted_bits;

748 RateControlContext *rcc = &s->rc_context;

749 AVCodecContext *a = s->avctx;

750 RateControlEntry local_rce, *rce;

751 double bits;

752 double rate_factor;

753 int var;

754 const int pict_type = s->pict_type;

755 Picture * const pic = &s->current_picture;

756 emms_c();

757

758 #if CONFIG_LIBXVID

759 if ((s->flags & CODEC_FLAG_PASS2) &&

760 s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)

761 return ff_xvid_rate_estimate_qscale(s, dry_run);

762 #endif

763

764 get_qminmax(&qmin, &qmax, s, pict_type);

765

766 fps = get_fps(s->avctx);

767 /* update predictors */

768 if (picture_number > 2 && !dry_run) {

769 const int last_var = s->last_pict_type == AV_PICTURE_TYPE_I ? rcc->last_mb_var_sum

770 : rcc->last_mc_mb_var_sum;

771 av_assert1(s->frame_bits >= s->stuffing_bits);

772 update_predictor(&rcc->pred[s->last_pict_type],

773 rcc->last_qscale,

774 sqrt(last_var),

775 s->frame_bits - s->stuffing_bits);

776 }

777

778 if (s->flags & CODEC_FLAG_PASS2) {

779 assert(picture_number >= 0);

780 if (picture_number >= rcc->num_entries) {

781 av_log(s, AV_LOG_ERROR, "Input is longer than 2-pass log file\n");

782 return -1;

783 }

784 rce = &rcc->entry[picture_number];

785 wanted_bits = rce->expected_bits;

786 } else {

787 Picture *dts_pic;

788 rce = &local_rce;

789

790 /* FIXME add a dts field to AVFrame and ensure it is set and use it

791 * here instead of reordering but the reordering is simpler for now

792 * until H.264 B-pyramid must be handled. */

793 if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay)

794 dts_pic = s->current_picture_ptr;

795 else

796 dts_pic = s->last_picture_ptr;

797

798 if (!dts_pic || dts_pic->f.pts == AV_NOPTS_VALUE)

799 wanted_bits = (uint64_t)(s->bit_rate * (double)picture_number / fps);

800 else

801 wanted_bits = (uint64_t)(s->bit_rate * (double)dts_pic->f.pts / fps);

802 }

803

804 diff = s->total_bits - wanted_bits;

805 br_compensation = (a->bit_rate_tolerance - diff) / a->bit_rate_tolerance;

806 if (br_compensation <= 0.0)

807 br_compensation = 0.001;

808

809 var = pict_type == AV_PICTURE_TYPE_I ? pic->mb_var_sum : pic->mc_mb_var_sum;

810

811 short_term_q = 0; /* avoid warning */

812 if (s->flags & CODEC_FLAG_PASS2) {

813 if (pict_type != AV_PICTURE_TYPE_I)

814 assert(pict_type == rce->new_pict_type);

815

816 q = rce->new_qscale / br_compensation;

817 av_dlog(s, "%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale,

818 br_compensation, s->frame_bits, var, pict_type);

819 } else {

820 rce->pict_type =

821 rce->new_pict_type = pict_type;

822 rce->mc_mb_var_sum = pic->mc_mb_var_sum;

823 rce->mb_var_sum = pic->mb_var_sum;

824 rce->qscale = FF_QP2LAMBDA * 2;

825 rce->f_code = s->f_code;

826 rce->b_code = s->b_code;

827 rce->misc_bits = 1;

828

829 bits = predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));

830 if (pict_type == AV_PICTURE_TYPE_I) {

831 rce->i_count = s->mb_num;

832 rce->i_tex_bits = bits;

833 rce->p_tex_bits = 0;

834 rce->mv_bits = 0;

835 } else {

836 rce->i_count = 0; // FIXME we do know this approx

837 rce->i_tex_bits = 0;

838 rce->p_tex_bits = bits * 0.9;

839 rce->mv_bits = bits * 0.1;

840 }

841 rcc->i_cplx_sum[pict_type] += rce->i_tex_bits * rce->qscale;

842 rcc->p_cplx_sum[pict_type] += rce->p_tex_bits * rce->qscale;

843 rcc->mv_bits_sum[pict_type] += rce->mv_bits;

844 rcc->frame_count[pict_type]++;

845

846 bits = rce->i_tex_bits + rce->p_tex_bits;

847 rate_factor = rcc->pass1_wanted_bits /

848 rcc->pass1_rc_eq_output_sum * br_compensation;

849

850 q = get_qscale(s, rce, rate_factor, picture_number);

851 if (q < 0)

852 return -1;

853

854 assert(q > 0.0);

855 q = get_diff_limited_q(s, rce, q);

856 assert(q > 0.0);

857

858 // FIXME type dependent blur like in 2-pass

859 if (pict_type == AV_PICTURE_TYPE_P || s->intra_only) {

860 rcc->short_term_qsum *= a->qblur;

861 rcc->short_term_qcount *= a->qblur;

862

863 rcc->short_term_qsum += q;

864 rcc->short_term_qcount++;

865 q = short_term_q = rcc->short_term_qsum / rcc->short_term_qcount;

866 }

867 assert(q > 0.0);

868

869 q = modify_qscale(s, rce, q, picture_number);

870

871 rcc->pass1_wanted_bits += s->bit_rate / fps;

872

873 assert(q > 0.0);

874 }

875

876 if (s->avctx->debug & FF_DEBUG_RC) {

877 av_log(s->avctx, AV_LOG_DEBUG,

878 "%c qp:%d<%2.1f<%d %d want:%d total:%d comp:%f st_q:%2.2f "

879 "size:%d var:%d/%d br:%d fps:%d\n",

880 av_get_picture_type_char(pict_type),

881 qmin, q, qmax, picture_number,

882 (int)wanted_bits / 1000, (int)s->total_bits / 1000,

883 br_compensation, short_term_q, s->frame_bits,

884 pic->mb_var_sum, pic->mc_mb_var_sum,

885 s->bit_rate / 1000, (int)fps);

886 }

887

888 if (q < qmin)

889 q = qmin;

890 else if (q > qmax)

891 q = qmax;

892

893 if (s->adaptive_quant)

894 adaptive_quantization(s, q);

895 else

896 q = (int)(q + 0.5);

897

898 if (!dry_run) {

899 rcc->last_qscale = q;

900 rcc->last_mc_mb_var_sum = pic->mc_mb_var_sum;

901 rcc->last_mb_var_sum = pic->mb_var_sum;

902 }

903 return q;

904 }

905

906 // ----------------------------------------------

907 // 2-Pass code

908

909 static int init_pass2(MpegEncContext *s)

910 {

911 RateControlContext *rcc = &s->rc_context;

912 AVCodecContext *a = s->avctx;

913 int i, toobig;

914 double fps = get_fps(s->avctx);

915 double complexity[5] = { 0 }; // approximate bits at quant=1

916 uint64_t const_bits[5] = { 0 }; // quantizer independent bits

917 uint64_t all_const_bits;

918 uint64_t all_available_bits = (uint64_t)(s->bit_rate *

919 (double)rcc->num_entries / fps);

920 double rate_factor = 0;

921 double step;

922 const int filter_size = (int)(a->qblur * 4) | 1;

923 double expected_bits = 0; // init to silence gcc warning

924 double *qscale, *blurred_qscale, qscale_sum;

925

926 /* find complexity & const_bits & decide the pict_types */

927 for (i = 0; i < rcc->num_entries; i++) {

928 RateControlEntry *rce = &rcc->entry[i];

929

930 rce->new_pict_type = rce->pict_type;

931 rcc->i_cplx_sum[rce->pict_type] += rce->i_tex_bits * rce->qscale;

932 rcc->p_cplx_sum[rce->pict_type] += rce->p_tex_bits * rce->qscale;

933 rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;

934 rcc->frame_count[rce->pict_type]++;

935

936 complexity[rce->new_pict_type] += (rce->i_tex_bits + rce->p_tex_bits) *

937 (double)rce->qscale;

938 const_bits[rce->new_pict_type] += rce->mv_bits + rce->misc_bits;

939 }

940

941 all_const_bits = const_bits[AV_PICTURE_TYPE_I] +

942 const_bits[AV_PICTURE_TYPE_P] +

943 const_bits[AV_PICTURE_TYPE_B];

944

945 if (all_available_bits < all_const_bits) {

946 av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is too low\n");

947 return -1;

948 }

949

950 qscale = av_malloc(sizeof(double) * rcc->num_entries);

951 blurred_qscale = av_malloc(sizeof(double) * rcc->num_entries);

952 toobig = 0;

953

954 for (step = 256 * 256; step > 0.0000001; step *= 0.5) {

955 expected_bits = 0;

956 rate_factor += step;

957

958 rcc->buffer_index = s->avctx->rc_buffer_size / 2;

959

960 /* find qscale */

961 for (i = 0; i < rcc->num_entries; i++) {

962 RateControlEntry *rce = &rcc->entry[i];

963

964 qscale[i] = get_qscale(s, &rcc->entry[i], rate_factor, i);

965 rcc->last_qscale_for[rce->pict_type] = qscale[i];

966 }

967 assert(filter_size % 2 == 1);

968

969 /* fixed I/B QP relative to P mode */

970 for (i = FFMAX(0, rcc->num_entries - 300); i < rcc->num_entries; i++) {

971 RateControlEntry *rce = &rcc->entry[i];

972

973 qscale[i] = get_diff_limited_q(s, rce, qscale[i]);

974 }

975

976 for (i = rcc->num_entries - 1; i >= 0; i--) {

977 RateControlEntry *rce = &rcc->entry[i];

978

979 qscale[i] = get_diff_limited_q(s, rce, qscale[i]);

980 }

981

982 /* smooth curve */

983 for (i = 0; i < rcc->num_entries; i++) {

984 RateControlEntry *rce = &rcc->entry[i];

985 const int pict_type = rce->new_pict_type;

986 int j;

987 double q = 0.0, sum = 0.0;

988

989 for (j = 0; j < filter_size; j++) {

990 int index = i + j - filter_size / 2;

991 double d = index - i;

992 double coeff = a->qblur == 0 ? 1.0 : exp(-d * d / (a->qblur * a->qblur));

993

994 if (index < 0 || index >= rcc->num_entries)

995 continue;

996 if (pict_type != rcc->entry[index].new_pict_type)

997 continue;

998 q += qscale[index] * coeff;

999 sum += coeff;

1000 }

1001 blurred_qscale[i] = q / sum;

1002 }

1003

1004 /* find expected bits */

1005 for (i = 0; i < rcc->num_entries; i++) {

1006 RateControlEntry *rce = &rcc->entry[i];

1007 double bits;

1008

1009 rce->new_qscale = modify_qscale(s, rce, blurred_qscale[i], i);

1010

1011 bits = qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;

1012 bits += 8 * ff_vbv_update(s, bits);

1013

1014 rce->expected_bits = expected_bits;

1015 expected_bits += bits;

1016 }

1017

1018 av_dlog(s->avctx,

1019 "expected_bits: %f all_available_bits: %d rate_factor: %f\n",

1020 expected_bits, (int)all_available_bits, rate_factor);

1021 if (expected_bits > all_available_bits) {

1022 rate_factor -= step;

1023 ++toobig;

1024 }

1025 }

1026 av_free(qscale);

1027 av_free(blurred_qscale);

1028

1029 /* check bitrate calculations and print info */

1030 qscale_sum = 0.0;

1031 for (i = 0; i < rcc->num_entries; i++) {

1032 av_dlog(s, "[lavc rc] entry[%d].new_qscale = %.3f qp = %.3f\n",

1033 i,

1034 rcc->entry[i].new_qscale,

1035 rcc->entry[i].new_qscale / FF_QP2LAMBDA);

1036 qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA,

1037 s->avctx->qmin, s->avctx->qmax);

1038 }

1039 assert(toobig <= 40);

1040 av_log(s->avctx, AV_LOG_DEBUG,

1041 "[lavc rc] requested bitrate: %d bps expected bitrate: %d bps\n",

1042 s->bit_rate,

1043 (int)(expected_bits / ((double)all_available_bits / s->bit_rate)));

1044 av_log(s->avctx, AV_LOG_DEBUG,

1045 "[lavc rc] estimated target average qp: %.3f\n",

1046 (float)qscale_sum / rcc->num_entries);

1047 if (toobig == 0) {

1048 av_log(s->avctx, AV_LOG_INFO,

1049 "[lavc rc] Using all of requested bitrate is not "

1050 "necessary for this video with these parameters.\n");

1051 } else if (toobig == 40) {

1052 av_log(s->avctx, AV_LOG_ERROR,

1053 "[lavc rc] Error: bitrate too low for this video "

1054 "with these parameters.\n");

1055 return -1;

1056 } else if (fabs(expected_bits / all_available_bits - 1.0) > 0.01) {

1057 av_log(s->avctx, AV_LOG_ERROR,

1058 "[lavc rc] Error: 2pass curve failed to converge\n");

1059 return -1;

1060 }

1061

1062 return 0;

1063 }

Generated on Wed Jul 10 2013 23:48:04 for FFmpeg by doxygen 1.8.2