libavcodec/av1_parse.c

   1 /*
   2  * AV1 common parsing code
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include "config.h"
  22
  23 #include "libavutil/mem.h"
  24
  25 #include "av1.h"
  26 #include "av1_parse.h"
  27 #include "bytestream.h"
  28
  29 int ff_av1_extract_obu(AV1OBU *obu, const uint8_t *buf, int length, void *logctx)
  30 {
  31     int64_t obu_size;
  32     int start_pos, type, temporal_id, spatial_id;
  33     int len;
  34
  35     len = parse_obu_header(buf, length, &obu_size, &start_pos,
  36                            &type, &temporal_id, &spatial_id);
  37     if (len < 0)
  38         return len;
  39
  40     obu->type        = type;
  41     obu->temporal_id = temporal_id;
  42     obu->spatial_id  = spatial_id;
  43
  44     obu->data     = buf + start_pos;
  45     obu->size     = obu_size;
  46     obu->raw_data = buf;
  47     obu->raw_size = len;
  48
  49     av_log(logctx, AV_LOG_DEBUG,
  50            "obu_type: %d, temporal_id: %d, spatial_id: %d, payload size: %d\n",
  51            obu->type, obu->temporal_id, obu->spatial_id, obu->size);
  52
  53     return len;
  54 }
  55
  56 int ff_av1_packet_split(AV1Packet *pkt, const uint8_t *buf, int length, void *logctx)
  57 {
  58     GetByteContext bc;
  59     int consumed;
  60
  61     bytestream2_init(&bc, buf, length);
  62     pkt->nb_obus = 0;
  63
  64     while (bytestream2_get_bytes_left(&bc) > 0) {
  65         AV1OBU *obu;
  66
  67         if (pkt->obus_allocated < pkt->nb_obus + 1) {
  68             int new_size = pkt->obus_allocated + 1;
  69             AV1OBU *tmp;
  70
  71             if (new_size >= INT_MAX / sizeof(*tmp))
  72                 return AVERROR(ENOMEM);
  73             tmp = av_fast_realloc(pkt->obus, &pkt->obus_allocated_size, new_size * sizeof(*tmp));
  74             if (!tmp)
  75                 return AVERROR(ENOMEM);
  76
  77             pkt->obus = tmp;
  78             memset(pkt->obus + pkt->obus_allocated, 0, sizeof(*pkt->obus));
  79             pkt->obus_allocated = new_size;
  80         }
  81         obu = &pkt->obus[pkt->nb_obus];
  82
  83         consumed = ff_av1_extract_obu(obu, bc.buffer, bytestream2_get_bytes_left(&bc), logctx);
  84         if (consumed < 0)
  85             return consumed;
  86
  87         bytestream2_skip(&bc, consumed);
  88
  89         obu->size_bits = get_obu_bit_length(obu->data, obu->size, obu->type);
  90
  91         if (obu->size_bits < 0 ||
  92             (obu->size_bits == 0 && (obu->type != AV1_OBU_TEMPORAL_DELIMITER &&
  93                                      obu->type != AV1_OBU_PADDING))) {
  94             av_log(logctx, AV_LOG_ERROR, "Invalid OBU of type %d, skipping.\n", obu->type);
  95             continue;
  96         }
  97
  98         pkt->nb_obus++;
  99     }
 100
 101     return 0;
 102 }
 103
 104 void ff_av1_packet_uninit(AV1Packet *pkt)
 105 {
 106     av_freep(&pkt->obus);
 107     pkt->obus_allocated = pkt->obus_allocated_size = 0;
 108 }
 109
 110 AVRational ff_av1_framerate(int64_t ticks_per_frame, int64_t units_per_tick,
 111                             int64_t time_scale)
 112 {
 113     AVRational fr;
 114
 115     if (ticks_per_frame && units_per_tick && time_scale &&
 116         ticks_per_frame < INT64_MAX / units_per_tick    &&
 117         av_reduce(&fr.den, &fr.num, units_per_tick * ticks_per_frame,
 118                   time_scale, INT_MAX))
 119         return fr;
 120
 121     return (AVRational){ 0, 1 };
 122 }