| 1 | /* |
| 2 | * Black ops audio demuxer |
| 3 | * Copyright (c) 2013 Michael Niedermayer |
| 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 | |
| 25 | static int probe(AVProbeData *p) |
| 26 | { |
| 27 | if (p->buf_size < 2096) |
| 28 | return 0; |
| 29 | if ( AV_RL32(p->buf ) != 1 |
| 30 | || AV_RL32(p->buf + 8) > 100000 |
| 31 | || AV_RL32(p->buf + 12) > 8 |
| 32 | || AV_RL32(p->buf + 16) != 2096 |
| 33 | ||!AV_RL32(p->buf + 21) |
| 34 | || AV_RL16(p->buf + 25) != 2096 |
| 35 | || AV_RL32(p->buf + 48) % AV_RL32(p->buf + 21) |
| 36 | ) |
| 37 | return 0; |
| 38 | return AVPROBE_SCORE_EXTENSION; |
| 39 | } |
| 40 | |
| 41 | |
| 42 | static int read_header(AVFormatContext *s) |
| 43 | { |
| 44 | AVStream *st = avformat_new_stream(s, NULL); |
| 45 | if (!st) |
| 46 | return AVERROR(ENOMEM); |
| 47 | |
| 48 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 49 | st->codec->codec_id = AV_CODEC_ID_ADPCM_MS; |
| 50 | |
| 51 | avio_rl32(s->pb); |
| 52 | avio_rl32(s->pb); |
| 53 | st->codec->sample_rate = avio_rl32(s->pb); |
| 54 | st->codec->channels = avio_rl32(s->pb); |
| 55 | s->data_offset = avio_rl32(s->pb); |
| 56 | avio_r8(s->pb); |
| 57 | st->codec->block_align = st->codec->channels * avio_rl32(s->pb); |
| 58 | |
| 59 | avio_seek(s->pb, s->data_offset, SEEK_SET); |
| 60 | |
| 61 | return 0; |
| 62 | } |
| 63 | |
| 64 | static int read_packet(AVFormatContext *s, AVPacket *pkt) |
| 65 | { |
| 66 | AVStream *st = s->streams[0]; |
| 67 | |
| 68 | return av_get_packet(s->pb, pkt, st->codec->block_align); |
| 69 | } |
| 70 | |
| 71 | AVInputFormat ff_boa_demuxer = { |
| 72 | .name = "boa", |
| 73 | .long_name = NULL_IF_CONFIG_SMALL("Black Ops Audio"), |
| 74 | .read_probe = probe, |
| 75 | .read_header = read_header, |
| 76 | .read_packet = read_packet, |
| 77 | .flags = AVFMT_GENERIC_INDEX, |
| 78 | }; |