1/* 2 * HCA demuxer 3 * Copyright (c) 2020 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 "libavcodec/bytestream.h" 24 25#include "avformat.h" 26#include "internal.h" 27 28static int hca_probe(const AVProbeData *p) 29{ 30 if (AV_RL32(p->buf) != MKTAG('H', 'C', 'A', 0)) 31 return 0; 32 33 if (AV_RL32(p->buf + 8) != MKTAG('f', 'm', 't', 0)) 34 return 0; 35 36 return AVPROBE_SCORE_MAX / 3; 37} 38 39static int hca_read_header(AVFormatContext *s) 40{ 41 AVCodecParameters *par; 42 GetByteContext gb; 43 AVIOContext *pb = s->pb; 44 AVStream *st; 45 uint32_t chunk; 46 uint16_t version; 47 uint32_t block_count; 48 uint16_t block_size, data_offset; 49 int ret; 50 51 avio_skip(pb, 4); 52 version = avio_rb16(pb); 53 54 data_offset = avio_rb16(pb); 55 if (data_offset <= 8) 56 return AVERROR_INVALIDDATA; 57 58 st = avformat_new_stream(s, NULL); 59 if (!st) 60 return AVERROR(ENOMEM); 61 62 par = st->codecpar; 63 ret = ff_alloc_extradata(par, data_offset); 64 if (ret < 0) 65 return ret; 66 67 ret = avio_read(pb, par->extradata + 8, par->extradata_size - 8); 68 if (ret < par->extradata_size - 8) 69 return AVERROR(EIO); 70 AV_WL32(par->extradata, MKTAG('H', 'C', 'A', 0)); 71 AV_WB16(par->extradata + 4, version); 72 AV_WB16(par->extradata + 6, data_offset); 73 74 bytestream2_init(&gb, par->extradata + 8, par->extradata_size - 8); 75 76 if (bytestream2_get_le32(&gb) != MKTAG('f', 'm', 't', 0)) 77 return AVERROR_INVALIDDATA; 78 79 par->codec_type = AVMEDIA_TYPE_AUDIO; 80 par->codec_id = AV_CODEC_ID_HCA; 81 par->codec_tag = 0; 82 st->codecpar->ch_layout.nb_channels = bytestream2_get_byte(&gb); 83 par->sample_rate = bytestream2_get_be24(&gb); 84 block_count = bytestream2_get_be32(&gb); 85 bytestream2_skip(&gb, 4); 86 chunk = bytestream2_get_le32(&gb); 87 if (chunk == MKTAG('c', 'o', 'm', 'p')) { 88 block_size = bytestream2_get_be16(&gb); 89 } else if (chunk == MKTAG('d', 'e', 'c', 0)) { 90 block_size = bytestream2_get_be16(&gb); 91 } else { 92 return AVERROR_INVALIDDATA; 93 } 94 95 if (block_size < 8) 96 return AVERROR_INVALIDDATA; 97 par->block_align = block_size; 98 st->duration = 1024 * block_count; 99 100 avio_seek(pb, data_offset, SEEK_SET); 101 avpriv_set_pts_info(st, 64, 1, par->sample_rate); 102 103 return 0; 104} 105 106static int hca_read_packet(AVFormatContext *s, AVPacket *pkt) 107{ 108 AVCodecParameters *par = s->streams[0]->codecpar; 109 int ret; 110 111 ret = av_get_packet(s->pb, pkt, par->block_align); 112 pkt->duration = 1024; 113 return ret; 114} 115 116const AVInputFormat ff_hca_demuxer = { 117 .name = "hca", 118 .long_name = NULL_IF_CONFIG_SMALL("CRI HCA"), 119 .read_probe = hca_probe, 120 .read_header = hca_read_header, 121 .read_packet = hca_read_packet, 122 .extensions = "hca", 123 .flags = AVFMT_GENERIC_INDEX, 124}; 125