| /* |
| * Simon & Schuster Interactive VAG demuxer |
| * |
| * Copyright (C) 2020 Zane van Iperen (zane@zanevaniperen.com) |
| * |
| * 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 "avformat.h" |
| #include "internal.h" |
| #include "libavutil/intreadwrite.h" |
| |
| #define KVAG_TAG MKTAG('K', 'V', 'A', 'G') |
| #define KVAG_HEADER_SIZE 14 |
| #define KVAG_MAX_READ_SIZE 4096 |
| |
| typedef struct KVAGHeader { |
| uint32_t magic; |
| uint32_t data_size; |
| uint32_t sample_rate; |
| uint16_t stereo; |
| } KVAGHeader; |
| |
| static int kvag_probe(const AVProbeData *p) |
| { |
| if (AV_RL32(p->buf) != KVAG_TAG) |
| return 0; |
| |
| return AVPROBE_SCORE_EXTENSION + 1; |
| } |
| |
| static int kvag_read_header(AVFormatContext *s) |
| { |
| int ret; |
| AVStream *st; |
| KVAGHeader hdr; |
| AVCodecParameters *par; |
| uint8_t buf[KVAG_HEADER_SIZE]; |
| |
| if (!(st = avformat_new_stream(s, NULL))) |
| return AVERROR(ENOMEM); |
| |
| if ((ret = avio_read(s->pb, buf, KVAG_HEADER_SIZE)) < 0) |
| return ret; |
| else if (ret != KVAG_HEADER_SIZE) |
| return AVERROR(EIO); |
| |
| hdr.magic = AV_RL32(buf + 0); |
| hdr.data_size = AV_RL32(buf + 4); |
| hdr.sample_rate = AV_RL32(buf + 8); |
| hdr.stereo = AV_RL16(buf + 12); |
| |
| par = st->codecpar; |
| par->codec_type = AVMEDIA_TYPE_AUDIO; |
| par->codec_id = AV_CODEC_ID_ADPCM_IMA_SSI; |
| par->format = AV_SAMPLE_FMT_S16; |
| |
| if (hdr.stereo) { |
| par->channel_layout = AV_CH_LAYOUT_STEREO; |
| par->channels = 2; |
| } else { |
| par->channel_layout = AV_CH_LAYOUT_MONO; |
| par->channels = 1; |
| } |
| |
| par->sample_rate = hdr.sample_rate; |
| par->bits_per_coded_sample = 4; |
| par->bits_per_raw_sample = 16; |
| par->block_align = 1; |
| par->bit_rate = par->channels * |
| par->sample_rate * |
| par->bits_per_coded_sample; |
| |
| avpriv_set_pts_info(st, 64, 1, par->sample_rate); |
| st->start_time = 0; |
| st->duration = hdr.data_size * |
| (8 / par->bits_per_coded_sample) / |
| par->channels; |
| |
| return 0; |
| } |
| |
| static int kvag_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| int ret; |
| AVCodecParameters *par = s->streams[0]->codecpar; |
| |
| if ((ret = av_get_packet(s->pb, pkt, KVAG_MAX_READ_SIZE)) < 0) |
| return ret; |
| |
| pkt->flags &= ~AV_PKT_FLAG_CORRUPT; |
| pkt->stream_index = 0; |
| pkt->duration = ret * (8 / par->bits_per_coded_sample) / par->channels; |
| |
| return 0; |
| } |
| |
| AVInputFormat ff_kvag_demuxer = { |
| .name = "kvag", |
| .long_name = NULL_IF_CONFIG_SMALL("Simon & Schuster Interactive VAG"), |
| .read_probe = kvag_probe, |
| .read_header = kvag_read_header, |
| .read_packet = kvag_read_packet |
| }; |