| /* |
| * SDNS demuxer |
| * Copyright (c) 2023 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/channel_layout.h" |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| #include "demux.h" |
| #include "internal.h" |
| |
| static int sdns_probe(const AVProbeData *p) |
| { |
| if (AV_RL32(p->buf) != MKTAG('S','D','N','S')) |
| return 0; |
| if (AV_RB32(p->buf + 8) <= 0) |
| return 0; |
| if (AV_RB32(p->buf + 12) <= 0 || |
| AV_RB32(p->buf + 12) > 128) |
| return 0; |
| return AVPROBE_SCORE_MAX / 3; |
| } |
| |
| static int sdns_read_header(AVFormatContext *s) |
| { |
| AVIOContext *pb = s->pb; |
| AVCodecParameters *par; |
| int channels, ret; |
| AVStream *st; |
| |
| avio_skip(pb, 8); |
| |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| par = st->codecpar; |
| par->codec_type = AVMEDIA_TYPE_AUDIO; |
| par->codec_id = AV_CODEC_ID_XMA1; |
| par->sample_rate = avio_rb32(pb); |
| channels = avio_rb32(pb); |
| if (channels <= 0 || channels > 128) |
| return AVERROR_INVALIDDATA; |
| av_channel_layout_default(&par->ch_layout, channels); |
| if (par->sample_rate <= 0) |
| return AVERROR_INVALIDDATA; |
| par->block_align = 2048; |
| if ((ret = ff_alloc_extradata(par, 8 + 20 * ((channels + 1) / 2))) < 0) |
| return ret; |
| memset(par->extradata, 0, 28); |
| par->extradata[4] = (channels + 1) / 2; |
| for (int i = 0; i < par->extradata[4]; i++) |
| par->extradata[8 + 20 * i + 17] = FFMIN(2, channels - i * 2); |
| avpriv_set_pts_info(st, 64, 1, par->sample_rate); |
| avio_seek(pb, 0x1000, SEEK_SET); |
| |
| return 0; |
| } |
| |
| static int sdns_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| int ret; |
| |
| if (avio_feof(s->pb)) |
| return AVERROR_EOF; |
| ret = av_get_packet(s->pb, pkt, 2048); |
| pkt->stream_index = 0; |
| |
| return ret; |
| } |
| |
| const AVInputFormat ff_sdns_demuxer = { |
| .name = "sdns", |
| .long_name = NULL_IF_CONFIG_SMALL("Xbox SDNS"), |
| .read_probe = sdns_probe, |
| .read_header = sdns_read_header, |
| .read_packet = sdns_read_packet, |
| .flags = AVFMT_GENERIC_INDEX, |
| .extensions = "sdns", |
| }; |