libavformat/qoadec.c

   1 /*
   2  * QOA demuxer
   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 "avformat.h"
  22 #include "avio_internal.h"
  23 #include "demux.h"
  24 #include "internal.h"
  25 #include "libavutil/intreadwrite.h"
  26
  27 static int qoa_probe(const AVProbeData *p)
  28 {
  29     if ((p->buf_size < 16) ||
  30         (AV_RB32(p->buf) != MKBETAG('q','o','a','f')) ||
  31         (AV_RB32(p->buf + 4) == 0) ||
  32         (p->buf[8] == 0) ||
  33         (AV_RB24(p->buf + 9) == 0) ||
  34         (AV_RB16(p->buf + 12) == 0) ||
  35         (AV_RB16(p->buf + 14) == 0))
  36         return 0;
  37     return AVPROBE_SCORE_MAX;
  38 }
  39
  40 static int qoa_read_header(AVFormatContext *s)
  41 {
  42     AVIOContext *pb = s->pb;
  43     AVStream *st;
  44     int ret;
  45
  46     st = avformat_new_stream(s, NULL);
  47     if (!st)
  48         return AVERROR(ENOMEM);
  49
  50     avio_skip(pb, 4);
  51     st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
  52     st->codecpar->codec_id = AV_CODEC_ID_QOA;
  53     st->duration = avio_rb32(pb);
  54     st->start_time = 0;
  55
  56     ret = ffio_ensure_seekback(pb, 4);
  57     if (ret < 0)
  58         return ret;
  59     st->codecpar->ch_layout.nb_channels = avio_r8(pb);
  60     if (st->codecpar->ch_layout.nb_channels == 0)
  61         return AVERROR_INVALIDDATA;
  62
  63     st->codecpar->sample_rate = avio_rb24(pb);
  64     if (st->codecpar->sample_rate == 0)
  65         return AVERROR_INVALIDDATA;
  66
  67     avio_seek(pb, -4, SEEK_CUR);
  68
  69     avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
  70
  71     return 0;
  72 }
  73
  74 static int qoa_read_packet(AVFormatContext *s, AVPacket *pkt)
  75 {
  76     AVIOContext *pb = s->pb;
  77     uint16_t size, duration;
  78     uint8_t hdr[8];
  79     int64_t pos;
  80     int ret;
  81
  82     if (avio_feof(pb))
  83         return AVERROR_EOF;
  84
  85     pos = avio_tell(pb);
  86     ret = avio_read(pb, hdr, sizeof(hdr));
  87     if (ret != sizeof(hdr))
  88         return AVERROR_EOF;
  89
  90     duration = AV_RB16(hdr + 4);
  91     size = AV_RB16(hdr + 6);
  92     if ((ret = av_new_packet(pkt, size)) < 0)
  93         return ret;
  94
  95     memcpy(pkt->data, hdr, sizeof(hdr));
  96     ret = ffio_read_size(pb, pkt->data + sizeof(hdr), size - sizeof(hdr));
  97     if (ret < 0)
  98         return ret;
  99     pkt->stream_index = 0;
 100     pkt->pos = pos;
 101     pkt->duration = duration;
 102
 103     return 0;
 104 }
 105
 106 const FFInputFormat ff_qoa_demuxer = {
 107     .p.name         = "qoa",
 108     .p.long_name    = NULL_IF_CONFIG_SMALL("QOA"),
 109     .p.flags        = AVFMT_GENERIC_INDEX,
 110     .p.extensions   = "qoa",
 111     .read_probe     = qoa_probe,
 112     .read_header    = qoa_read_header,
 113     .read_packet    = qoa_read_packet,
 114 };