| /* |
| * HCOM demuxer |
| * Copyright (c) 2019 Paul B Mahol |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "libavutil/intreadwrite.h" |
| #include "libavcodec/internal.h" |
| #include "avformat.h" |
| #include "internal.h" |
| #include "pcm.h" |
| |
| static int hcom_probe(const AVProbeData *p) |
| { |
| if (p->buf_size < 132) |
| return 0; |
| if (!memcmp(p->buf+65, "FSSD", 4) && |
| !memcmp(p->buf+128, "HCOM", 4)) |
| return AVPROBE_SCORE_MAX; |
| return 0; |
| } |
| |
| static int hcom_read_header(AVFormatContext *s) |
| { |
| AVStream *st; |
| av_unused unsigned data_size, rsrc_size, huffcount; |
| unsigned compresstype, divisor; |
| unsigned dict_entries; |
| int ret; |
| |
| avio_skip(s->pb, 83); |
| data_size = avio_rb32(s->pb); |
| rsrc_size = avio_rb32(s->pb); |
| avio_skip(s->pb, 128-91+4); |
| huffcount = avio_rb32(s->pb); |
| avio_skip(s->pb, 4); |
| compresstype = avio_rb32(s->pb); |
| if (compresstype > 1) |
| return AVERROR_INVALIDDATA; |
| divisor = avio_rb32(s->pb); |
| if (divisor == 0 || divisor > 4) |
| return AVERROR_INVALIDDATA; |
| dict_entries = avio_rb16(s->pb); |
| |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codecpar->channels = 1; |
| st->codecpar->sample_rate = 22050 / divisor; |
| st->codecpar->codec_id = AV_CODEC_ID_HCOM; |
| st->codecpar->bits_per_coded_sample = 8; |
| st->codecpar->block_align = 4; |
| |
| ret = ff_alloc_extradata(st->codecpar, dict_entries * 4 + 7); |
| if (ret < 0) |
| return ret; |
| AV_WB16(st->codecpar->extradata, dict_entries); |
| AV_WB32(st->codecpar->extradata + 2, compresstype); |
| avio_read(s->pb, st->codecpar->extradata + 6, dict_entries * 4); |
| avio_skip(s->pb, 1); |
| st->codecpar->extradata[dict_entries * 4 + 6] = avio_r8(s->pb); |
| |
| avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate); |
| |
| return 0; |
| } |
| |
| AVInputFormat ff_hcom_demuxer = { |
| .name = "hcom", |
| .long_name = NULL_IF_CONFIG_SMALL("Macintosh HCOM"), |
| .read_probe = hcom_probe, |
| .read_header = hcom_read_header, |
| .read_packet = ff_pcm_read_packet, |
| }; |