libavcodec/hevc_refs.c

   1 /*
   2  * HEVC video decoder
   3  *
   4  * Copyright (C) 2012 - 2013 Guillaume Martres
   5  * Copyright (C) 2012 - 2013 Gildas Cocherel
   6  *
   7  * This file is part of Libav.
   8  *
   9  * Libav is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * Libav is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with Libav; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #include "libavutil/avassert.h"
  25 #include "libavutil/pixdesc.h"
  26
  27 #include "internal.h"
  28 #include "thread.h"
  29 #include "hevc.h"
  30 #include "hevcdec.h"
  31
  32 void ff_hevc_unref_frame(HEVCContext *s, HEVCFrame *frame, int flags)
  33 {
  34     /* frame->frame can be NULL if context init failed */
  35     if (!frame->frame || !frame->frame->buf[0])
  36         return;
  37
  38     frame->flags &= ~flags;
  39     if (!frame->flags) {
  40         ff_thread_release_buffer(s->avctx, &frame->tf);
  41
  42         av_buffer_unref(&frame->tab_mvf_buf);
  43         frame->tab_mvf = NULL;
  44
  45         av_buffer_unref(&frame->rpl_buf);
  46         av_buffer_unref(&frame->rpl_tab_buf);
  47         frame->rpl_tab    = NULL;
  48         frame->refPicList = NULL;
  49
  50         frame->collocated_ref = NULL;
  51
  52         av_buffer_unref(&frame->hwaccel_priv_buf);
  53         frame->hwaccel_picture_private = NULL;
  54     }
  55 }
  56
  57 RefPicList *ff_hevc_get_ref_list(HEVCContext *s, HEVCFrame *ref, int x0, int y0)
  58 {
  59     int x_cb         = x0 >> s->ps.sps->log2_ctb_size;
  60     int y_cb         = y0 >> s->ps.sps->log2_ctb_size;
  61     int pic_width_cb = (s->ps.sps->width + (1 << s->ps.sps->log2_ctb_size) - 1) >>
  62         s->ps.sps->log2_ctb_size;
  63     int ctb_addr_ts  = s->ps.pps->ctb_addr_rs_to_ts[y_cb * pic_width_cb + x_cb];
  64     return (RefPicList *)ref->rpl_tab[ctb_addr_ts];
  65 }
  66
  67 void ff_hevc_clear_refs(HEVCContext *s)
  68 {
  69     int i;
  70     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++)
  71         ff_hevc_unref_frame(s, &s->DPB[i],
  72                             HEVC_FRAME_FLAG_SHORT_REF |
  73                             HEVC_FRAME_FLAG_LONG_REF);
  74 }
  75
  76 void ff_hevc_flush_dpb(HEVCContext *s)
  77 {
  78     int i;
  79     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++)
  80         ff_hevc_unref_frame(s, &s->DPB[i], ~0);
  81 }
  82
  83 static HEVCFrame *alloc_frame(HEVCContext *s)
  84 {
  85     int i, j, ret;
  86     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) {
  87         HEVCFrame *frame = &s->DPB[i];
  88         if (frame->frame->buf[0])
  89             continue;
  90
  91         ret = ff_thread_get_buffer(s->avctx, &frame->tf,
  92                                    AV_GET_BUFFER_FLAG_REF);
  93         if (ret < 0)
  94             return NULL;
  95
  96         frame->rpl_buf = av_buffer_allocz(s->pkt.nb_nals * sizeof(RefPicListTab));
  97         if (!frame->rpl_buf)
  98             goto fail;
  99
 100         frame->tab_mvf_buf = av_buffer_pool_get(s->tab_mvf_pool);
 101         if (!frame->tab_mvf_buf)
 102             goto fail;
 103         frame->tab_mvf = (MvField *)frame->tab_mvf_buf->data;
 104
 105         frame->rpl_tab_buf = av_buffer_pool_get(s->rpl_tab_pool);
 106         if (!frame->rpl_tab_buf)
 107             goto fail;
 108         frame->rpl_tab   = (RefPicListTab **)frame->rpl_tab_buf->data;
 109         frame->ctb_count = s->ps.sps->ctb_width * s->ps.sps->ctb_height;
 110         for (j = 0; j < frame->ctb_count; j++)
 111             frame->rpl_tab[j] = (RefPicListTab *)frame->rpl_buf->data;
 112
 113         if (s->avctx->hwaccel) {
 114             const AVHWAccel *hwaccel = s->avctx->hwaccel;
 115             av_assert0(!frame->hwaccel_picture_private);
 116             if (hwaccel->frame_priv_data_size) {
 117                 frame->hwaccel_priv_buf = av_buffer_allocz(hwaccel->frame_priv_data_size);
 118                 if (!frame->hwaccel_priv_buf)
 119                     goto fail;
 120                 frame->hwaccel_picture_private = frame->hwaccel_priv_buf->data;
 121             }
 122         }
 123
 124         return frame;
 125
 126 fail:
 127         ff_hevc_unref_frame(s, frame, ~0);
 128         return NULL;
 129     }
 130     av_log(s->avctx, AV_LOG_ERROR, "Error allocating frame, DPB full.\n");
 131     return NULL;
 132 }
 133
 134 int ff_hevc_set_new_ref(HEVCContext *s, AVFrame **frame, int poc)
 135 {
 136     HEVCFrame *ref;
 137     int i;
 138
 139     /* check that this POC doesn't already exist */
 140     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) {
 141         HEVCFrame *frame = &s->DPB[i];
 142
 143         if (frame->frame->buf[0] && frame->sequence == s->seq_decode &&
 144             frame->poc == poc) {
 145             av_log(s->avctx, AV_LOG_ERROR, "Duplicate POC in a sequence: %d.\n",
 146                    poc);
 147             return AVERROR_INVALIDDATA;
 148         }
 149     }
 150
 151     ref = alloc_frame(s);
 152     if (!ref)
 153         return AVERROR(ENOMEM);
 154
 155     *frame = ref->frame;
 156     s->ref = ref;
 157
 158     if (s->sh.pic_output_flag)
 159         ref->flags = HEVC_FRAME_FLAG_OUTPUT | HEVC_FRAME_FLAG_SHORT_REF;
 160     else
 161         ref->flags = HEVC_FRAME_FLAG_SHORT_REF;
 162
 163     ref->poc      = poc;
 164     ref->sequence = s->seq_decode;
 165     ref->frame->crop_left   = s->ps.sps->output_window.left_offset;
 166     ref->frame->crop_right  = s->ps.sps->output_window.right_offset;
 167     ref->frame->crop_top    = s->ps.sps->output_window.top_offset;
 168     ref->frame->crop_bottom = s->ps.sps->output_window.bottom_offset;
 169
 170     return 0;
 171 }
 172
 173 int ff_hevc_output_frame(HEVCContext *s, AVFrame *out, int flush)
 174 {
 175     do {
 176         int nb_output = 0;
 177         int min_poc   = INT_MAX;
 178         int i, min_idx, ret;
 179
 180         for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) {
 181             HEVCFrame *frame = &s->DPB[i];
 182             if ((frame->flags & HEVC_FRAME_FLAG_OUTPUT) &&
 183                 frame->sequence == s->seq_output) {
 184                 nb_output++;
 185                 if (frame->poc < min_poc) {
 186                     min_poc = frame->poc;
 187                     min_idx = i;
 188                 }
 189             }
 190         }
 191
 192         /* wait for more frames before output */
 193         if (!flush && s->seq_output == s->seq_decode && s->ps.sps &&
 194             nb_output <= s->ps.sps->temporal_layer[s->ps.sps->max_sub_layers - 1].num_reorder_pics)
 195             return 0;
 196
 197         if (nb_output) {
 198             HEVCFrame *frame = &s->DPB[min_idx];
 199
 200             ret = av_frame_ref(out, frame->frame);
 201             ff_hevc_unref_frame(s, frame, HEVC_FRAME_FLAG_OUTPUT);
 202             if (ret < 0)
 203                 return ret;
 204
 205             av_log(s->avctx, AV_LOG_DEBUG,
 206                    "Output frame with POC %d.\n", frame->poc);
 207             return 1;
 208         }
 209
 210         if (s->seq_output != s->seq_decode)
 211             s->seq_output = (s->seq_output + 1) & 0xff;
 212         else
 213             break;
 214     } while (1);
 215
 216     return 0;
 217 }
 218
 219 static int init_slice_rpl(HEVCContext *s)
 220 {
 221     HEVCFrame *frame = s->ref;
 222     int ctb_count    = frame->ctb_count;
 223     int ctb_addr_ts  = s->ps.pps->ctb_addr_rs_to_ts[s->sh.slice_segment_addr];
 224     int i;
 225
 226     if (s->slice_idx >= frame->rpl_buf->size / sizeof(RefPicListTab))
 227         return AVERROR_INVALIDDATA;
 228
 229     for (i = ctb_addr_ts; i < ctb_count; i++)
 230         frame->rpl_tab[i] = (RefPicListTab *)frame->rpl_buf->data + s->slice_idx;
 231
 232     frame->refPicList = (RefPicList *)frame->rpl_tab[ctb_addr_ts];
 233
 234     return 0;
 235 }
 236
 237 int ff_hevc_slice_rpl(HEVCContext *s)
 238 {
 239     SliceHeader *sh = &s->sh;
 240
 241     uint8_t nb_list = sh->slice_type == HEVC_SLICE_B ? 2 : 1;
 242     uint8_t list_idx;
 243     int i, j, ret;
 244
 245     ret = init_slice_rpl(s);
 246     if (ret < 0)
 247         return ret;
 248
 249     if (!(s->rps[ST_CURR_BEF].nb_refs + s->rps[ST_CURR_AFT].nb_refs +
 250           s->rps[LT_CURR].nb_refs)) {
 251         av_log(s->avctx, AV_LOG_ERROR, "Zero refs in the frame RPS.\n");
 252         return AVERROR_INVALIDDATA;
 253     }
 254
 255     for (list_idx = 0; list_idx < nb_list; list_idx++) {
 256         RefPicList  rpl_tmp = { { 0 } };
 257         RefPicList *rpl     = &s->ref->refPicList[list_idx];
 258
 259         /* The order of the elements is
 260          * ST_CURR_BEF - ST_CURR_AFT - LT_CURR for the L0 and
 261          * ST_CURR_AFT - ST_CURR_BEF - LT_CURR for the L1 */
 262         int cand_lists[3] = { list_idx ? ST_CURR_AFT : ST_CURR_BEF,
 263                               list_idx ? ST_CURR_BEF : ST_CURR_AFT,
 264                               LT_CURR };
 265
 266         /* concatenate the candidate lists for the current frame */
 267         while (rpl_tmp.nb_refs < sh->nb_refs[list_idx]) {
 268             for (i = 0; i < FF_ARRAY_ELEMS(cand_lists); i++) {
 269                 RefPicList *rps = &s->rps[cand_lists[i]];
 270                 for (j = 0; j < rps->nb_refs && rpl_tmp.nb_refs < HEVC_MAX_REFS; j++) {
 271                     rpl_tmp.list[rpl_tmp.nb_refs]       = rps->list[j];
 272                     rpl_tmp.ref[rpl_tmp.nb_refs]        = rps->ref[j];
 273                     rpl_tmp.isLongTerm[rpl_tmp.nb_refs] = i == 2;
 274                     rpl_tmp.nb_refs++;
 275                 }
 276             }
 277         }
 278
 279         /* reorder the references if necessary */
 280         if (sh->rpl_modification_flag[list_idx]) {
 281             for (i = 0; i < sh->nb_refs[list_idx]; i++) {
 282                 int idx = sh->list_entry_lx[list_idx][i];
 283
 284                 if (idx >= rpl_tmp.nb_refs) {
 285                     av_log(s->avctx, AV_LOG_ERROR, "Invalid reference index.\n");
 286                     return AVERROR_INVALIDDATA;
 287                 }
 288
 289                 rpl->list[i]       = rpl_tmp.list[idx];
 290                 rpl->ref[i]        = rpl_tmp.ref[idx];
 291                 rpl->isLongTerm[i] = rpl_tmp.isLongTerm[idx];
 292                 rpl->nb_refs++;
 293             }
 294         } else {
 295             memcpy(rpl, &rpl_tmp, sizeof(*rpl));
 296             rpl->nb_refs = FFMIN(rpl->nb_refs, sh->nb_refs[list_idx]);
 297         }
 298
 299         if (sh->collocated_list == list_idx &&
 300             sh->collocated_ref_idx < rpl->nb_refs)
 301             s->ref->collocated_ref = rpl->ref[sh->collocated_ref_idx];
 302     }
 303
 304     return 0;
 305 }
 306
 307 static HEVCFrame *find_ref_idx(HEVCContext *s, int poc)
 308 {
 309     int i;
 310     int LtMask = (1 << s->ps.sps->log2_max_poc_lsb) - 1;
 311
 312     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) {
 313         HEVCFrame *ref = &s->DPB[i];
 314         if (ref->frame->buf[0] && (ref->sequence == s->seq_decode)) {
 315             if ((ref->poc & LtMask) == poc)
 316                 return ref;
 317         }
 318     }
 319
 320     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) {
 321         HEVCFrame *ref = &s->DPB[i];
 322         if (ref->frame->buf[0] && ref->sequence == s->seq_decode) {
 323             if (ref->poc == poc || (ref->poc & LtMask) == poc)
 324                 return ref;
 325         }
 326     }
 327
 328     av_log(s->avctx, AV_LOG_ERROR,
 329            "Could not find ref with POC %d\n", poc);
 330     return NULL;
 331 }
 332
 333 static void mark_ref(HEVCFrame *frame, int flag)
 334 {
 335     frame->flags &= ~(HEVC_FRAME_FLAG_LONG_REF | HEVC_FRAME_FLAG_SHORT_REF);
 336     frame->flags |= flag;
 337 }
 338
 339 static HEVCFrame *generate_missing_ref(HEVCContext *s, int poc)
 340 {
 341     HEVCFrame *frame;
 342     int i, x, y;
 343
 344     frame = alloc_frame(s);
 345     if (!frame)
 346         return NULL;
 347
 348     if (!s->avctx->hwaccel) {
 349         if (!s->ps.sps->pixel_shift) {
 350             for (i = 0; frame->frame->buf[i]; i++)
 351                 memset(frame->frame->buf[i]->data, 1 << (s->ps.sps->bit_depth - 1),
 352                        frame->frame->buf[i]->size);
 353         } else {
 354             for (i = 0; frame->frame->data[i]; i++)
 355                 for (y = 0; y < (s->ps.sps->height >> s->ps.sps->vshift[i]); y++)
 356                     for (x = 0; x < (s->ps.sps->width >> s->ps.sps->hshift[i]); x++) {
 357                         AV_WN16(frame->frame->data[i] + y * frame->frame->linesize[i] + 2 * x,
 358                                 1 << (s->ps.sps->bit_depth - 1));
 359                     }
 360         }
 361     }
 362
 363     frame->poc      = poc;
 364     frame->sequence = s->seq_decode;
 365     frame->flags    = 0;
 366
 367     ff_thread_report_progress(&frame->tf, INT_MAX, 0);
 368
 369     return frame;
 370 }
 371
 372 /* add a reference with the given poc to the list and mark it as used in DPB */
 373 static int add_candidate_ref(HEVCContext *s, RefPicList *list,
 374                              int poc, int ref_flag)
 375 {
 376     HEVCFrame *ref = find_ref_idx(s, poc);
 377
 378     if (ref == s->ref)
 379         return AVERROR_INVALIDDATA;
 380
 381     if (!ref) {
 382         ref = generate_missing_ref(s, poc);
 383         if (!ref)
 384             return AVERROR(ENOMEM);
 385     }
 386
 387     list->list[list->nb_refs] = ref->poc;
 388     list->ref[list->nb_refs]  = ref;
 389     list->nb_refs++;
 390
 391     mark_ref(ref, ref_flag);
 392     return 0;
 393 }
 394
 395 int ff_hevc_frame_rps(HEVCContext *s)
 396 {
 397     const ShortTermRPS *short_rps = s->sh.short_term_rps;
 398     const LongTermRPS  *long_rps  = &s->sh.long_term_rps;
 399     RefPicList               *rps = s->rps;
 400     int i, ret = 0;
 401
 402     if (!short_rps) {
 403         rps[0].nb_refs = rps[1].nb_refs = 0;
 404         return 0;
 405     }
 406
 407     /* clear the reference flags on all frames except the current one */
 408     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++) {
 409         HEVCFrame *frame = &s->DPB[i];
 410
 411         if (frame == s->ref)
 412             continue;
 413
 414         mark_ref(frame, 0);
 415     }
 416
 417     for (i = 0; i < NB_RPS_TYPE; i++)
 418         rps[i].nb_refs = 0;
 419
 420     /* add the short refs */
 421     for (i = 0; i < short_rps->num_delta_pocs; i++) {
 422         int poc = s->poc + short_rps->delta_poc[i];
 423         int list;
 424
 425         if (!short_rps->used[i])
 426             list = ST_FOLL;
 427         else if (i < short_rps->num_negative_pics)
 428             list = ST_CURR_BEF;
 429         else
 430             list = ST_CURR_AFT;
 431
 432         ret = add_candidate_ref(s, &rps[list], poc, HEVC_FRAME_FLAG_SHORT_REF);
 433         if (ret < 0)
 434             goto fail;
 435     }
 436
 437     /* add the long refs */
 438     for (i = 0; i < long_rps->nb_refs; i++) {
 439         int poc  = long_rps->poc[i];
 440         int list = long_rps->used[i] ? LT_CURR : LT_FOLL;
 441
 442         ret = add_candidate_ref(s, &rps[list], poc, HEVC_FRAME_FLAG_LONG_REF);
 443         if (ret < 0)
 444             goto fail;
 445     }
 446
 447 fail:
 448     /* release any frames that are now unused */
 449     for (i = 0; i < FF_ARRAY_ELEMS(s->DPB); i++)
 450         ff_hevc_unref_frame(s, &s->DPB[i], 0);
 451
 452     return ret;
 453 }
 454
 455 int ff_hevc_compute_poc(HEVCContext *s, int poc_lsb)
 456 {
 457     int max_poc_lsb  = 1 << s->ps.sps->log2_max_poc_lsb;
 458     int prev_poc_lsb = s->pocTid0 % max_poc_lsb;
 459     int prev_poc_msb = s->pocTid0 - prev_poc_lsb;
 460     int poc_msb;
 461
 462     if (poc_lsb < prev_poc_lsb && prev_poc_lsb - poc_lsb >= max_poc_lsb / 2)
 463         poc_msb = prev_poc_msb + max_poc_lsb;
 464     else if (poc_lsb > prev_poc_lsb && poc_lsb - prev_poc_lsb > max_poc_lsb / 2)
 465         poc_msb = prev_poc_msb - max_poc_lsb;
 466     else
 467         poc_msb = prev_poc_msb;
 468
 469     // For BLA picture types, POCmsb is set to 0.
 470     if (s->nal_unit_type == HEVC_NAL_BLA_W_LP   ||
 471         s->nal_unit_type == HEVC_NAL_BLA_W_RADL ||
 472         s->nal_unit_type == HEVC_NAL_BLA_N_LP)
 473         poc_msb = 0;
 474
 475     return poc_msb + poc_lsb;
 476 }
 477
 478 int ff_hevc_frame_nb_refs(HEVCContext *s)
 479 {
 480     int ret = 0;
 481     int i;
 482     const ShortTermRPS *rps = s->sh.short_term_rps;
 483     LongTermRPS *long_rps   = &s->sh.long_term_rps;
 484
 485     if (rps) {
 486         for (i = 0; i < rps->num_negative_pics; i++)
 487             ret += !!rps->used[i];
 488         for (; i < rps->num_delta_pocs; i++)
 489             ret += !!rps->used[i];
 490     }
 491
 492     if (long_rps) {
 493         for (i = 0; i < long_rps->nb_refs; i++)
 494             ret += !!long_rps->used[i];
 495     }
 496     return ret;
 497 }