| /* |
| * SVS demuxer |
| * Copyright (c) 2020 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 "internal.h" |
| |
| static int svs_probe(const AVProbeData *p) |
| { |
| if (p->buf_size < 32) |
| return 0; |
| |
| if (memcmp(p->buf, "SVS\00", 4)) |
| return 0; |
| |
| if (AV_RL32(p->buf + 16) == 0) |
| return 0; |
| |
| return AVPROBE_SCORE_MAX / 3; |
| } |
| |
| static int svs_read_header(AVFormatContext *s) |
| { |
| AVStream *st; |
| uint32_t pitch; |
| |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| avio_skip(s->pb, 16); |
| pitch = avio_rl32(s->pb); |
| avio_skip(s->pb, 12); |
| |
| s->internal->data_offset = avio_tell(s->pb); |
| st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codecpar->codec_id = AV_CODEC_ID_ADPCM_PSX; |
| st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO; |
| st->codecpar->channels = 2; |
| st->codecpar->sample_rate = av_rescale_rnd(pitch, 48000, 4096, AV_ROUND_INF); |
| st->codecpar->block_align = 32; |
| st->start_time = 0; |
| if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) |
| st->duration = av_get_audio_frame_duration2(st->codecpar, |
| avio_size(s->pb) - 32); |
| |
| avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate); |
| |
| return 0; |
| } |
| |
| static int svs_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| int ret; |
| |
| if (avio_feof(s->pb)) |
| return AVERROR_EOF; |
| |
| ret = av_get_packet(s->pb, pkt, 32 * 256); |
| if (ret != 32 * 256) { |
| if (ret < 0) |
| return ret; |
| av_shrink_packet(pkt, ret); |
| pkt->flags &= ~AV_PKT_FLAG_CORRUPT; |
| } |
| pkt->stream_index = 0; |
| |
| return ret; |
| } |
| |
| AVInputFormat ff_svs_demuxer = { |
| .name = "svs", |
| .long_name = NULL_IF_CONFIG_SMALL("Square SVS"), |
| .read_probe = svs_probe, |
| .read_header = svs_read_header, |
| .read_packet = svs_read_packet, |
| .extensions = "svs", |
| }; |