libavformat/vpk.c

   1 /*
   2  * VPK demuxer
   3  * Copyright (c) 2015 Paul B Mahol
   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 #include "libavutil/intreadwrite.h"
  23 #include "avformat.h"
  24 #include "internal.h"
  25
  26 typedef struct VPKDemuxContext {
  27     unsigned data_start;
  28     unsigned block_count;
  29     unsigned current_block;
  30     unsigned last_block_size;
  31 } VPKDemuxContext;
  32
  33 static int vpk_probe(const AVProbeData *p)
  34 {
  35     if (AV_RL32(p->buf) != MKBETAG('V','P','K',' '))
  36         return 0;
  37
  38     return AVPROBE_SCORE_MAX / 3 * 2;
  39 }
  40
  41 static int vpk_read_header(AVFormatContext *s)
  42 {
  43     VPKDemuxContext *vpk = s->priv_data;
  44     unsigned offset;
  45     unsigned samples_per_block;
  46     AVStream *st;
  47
  48     vpk->current_block = 0;
  49     st = avformat_new_stream(s, NULL);
  50     if (!st)
  51         return AVERROR(ENOMEM);
  52
  53     avio_skip(s->pb, 4);
  54     st->duration           = avio_rl32(s->pb) * 28 / 16;
  55     offset                 = avio_rl32(s->pb);
  56     st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
  57     st->codecpar->codec_id    = AV_CODEC_ID_ADPCM_PSX;
  58     st->codecpar->block_align = avio_rl32(s->pb);
  59     st->codecpar->sample_rate = avio_rl32(s->pb);
  60     if (st->codecpar->sample_rate <= 0 || st->codecpar->block_align <= 0)
  61         return AVERROR_INVALIDDATA;
  62     st->codecpar->channels    = avio_rl32(s->pb);
  63     if (st->codecpar->channels <= 0)
  64         return AVERROR_INVALIDDATA;
  65     samples_per_block      = ((st->codecpar->block_align / st->codecpar->channels) * 28LL) / 16;
  66     if (samples_per_block <= 0)
  67         return AVERROR_INVALIDDATA;
  68     vpk->block_count       = (st->duration + (samples_per_block - 1)) / samples_per_block;
  69     vpk->last_block_size   = (st->duration % samples_per_block) * 16 * st->codecpar->channels / 28;
  70
  71     if (offset < avio_tell(s->pb))
  72         return AVERROR_INVALIDDATA;
  73     avio_skip(s->pb, offset - avio_tell(s->pb));
  74     vpk->data_start = offset;
  75     avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
  76
  77     return 0;
  78 }
  79
  80 static int vpk_read_packet(AVFormatContext *s, AVPacket *pkt)
  81 {
  82     AVCodecParameters *par = s->streams[0]->codecpar;
  83     VPKDemuxContext *vpk = s->priv_data;
  84     int ret, i;
  85
  86     vpk->current_block++;
  87     if (vpk->current_block == vpk->block_count) {
  88         unsigned size = vpk->last_block_size / par->channels;
  89         unsigned skip = (par->block_align - vpk->last_block_size) / par->channels;
  90         uint64_t pos = avio_tell(s->pb);
  91
  92         ret = av_new_packet(pkt, vpk->last_block_size);
  93         if (ret < 0)
  94             return ret;
  95         for (i = 0; i < par->channels; i++) {
  96             ret = avio_read(s->pb, pkt->data + i * size, size);
  97             avio_skip(s->pb, skip);
  98             if (ret != size) {
  99                 return AVERROR(EIO);
 100             }
 101         }
 102         pkt->pos = pos;
 103         pkt->stream_index = 0;
 104     } else if (vpk->current_block < vpk->block_count) {
 105         ret = av_get_packet(s->pb, pkt, par->block_align);
 106         pkt->stream_index = 0;
 107     } else {
 108         return AVERROR_EOF;
 109     }
 110
 111     return ret;
 112 }
 113
 114 static int vpk_read_seek(AVFormatContext *s, int stream_index,
 115                          int64_t timestamp, int flags)
 116 {
 117     AVStream *st = s->streams[stream_index];
 118     AVCodecParameters *par = st->codecpar;
 119     VPKDemuxContext *vpk = s->priv_data;
 120     int samples_per_block;
 121     int64_t ret = 0;
 122
 123     samples_per_block = av_get_audio_frame_duration2(par, par->block_align);
 124     timestamp /= samples_per_block;
 125     ret = avio_seek(s->pb, vpk->data_start + timestamp * par->block_align, SEEK_SET);
 126     if (ret < 0)
 127         return ret;
 128
 129     vpk->current_block = timestamp;
 130     ff_update_cur_dts(s, st, timestamp * samples_per_block);
 131     return 0;
 132 }
 133
 134 AVInputFormat ff_vpk_demuxer = {
 135     .name           = "vpk",
 136     .long_name      = NULL_IF_CONFIG_SMALL("Sony PS2 VPK"),
 137     .priv_data_size = sizeof(VPKDemuxContext),
 138     .read_probe     = vpk_probe,
 139     .read_header    = vpk_read_header,
 140     .read_packet    = vpk_read_packet,
 141     .read_seek      = vpk_read_seek,
 142     .extensions     = "vpk",
 143 };