| /* |
| * 3DO STR demuxer |
| * Copyright (c) 2015 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 "avformat.h" |
| #include "internal.h" |
| |
| static int threedostr_probe(AVProbeData *p) |
| { |
| if (memcmp(p->buf, "CTRL", 4) && |
| memcmp(p->buf, "SHDR", 4) && |
| memcmp(p->buf, "SNDS", 4)) |
| return 0; |
| |
| return AVPROBE_SCORE_MAX / 3 * 2; |
| } |
| |
| static int threedostr_read_header(AVFormatContext *s) |
| { |
| unsigned chunk, codec = 0, size, ctrl_size = -1, found_shdr = 0; |
| AVStream *st; |
| |
| while (!avio_feof(s->pb) && !found_shdr) { |
| chunk = avio_rl32(s->pb); |
| size = avio_rb32(s->pb); |
| |
| if (size < 8) |
| return AVERROR_INVALIDDATA; |
| size -= 8; |
| |
| switch (chunk) { |
| case MKTAG('C','T','R','L'): |
| ctrl_size = size; |
| break; |
| case MKTAG('S','N','D','S'): |
| if (size < 56) |
| return AVERROR_INVALIDDATA; |
| avio_skip(s->pb, 8); |
| if (avio_rl32(s->pb) != MKTAG('S','H','D','R')) |
| return AVERROR_INVALIDDATA; |
| avio_skip(s->pb, 24); |
| |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codec->sample_rate = avio_rb32(s->pb); |
| st->codec->channels = avio_rb32(s->pb); |
| if (st->codec->channels <= 0) |
| return AVERROR_INVALIDDATA; |
| codec = avio_rl32(s->pb); |
| avio_skip(s->pb, 4); |
| if (ctrl_size == 20 || ctrl_size == 3 || ctrl_size == -1) |
| st->duration = (avio_rb32(s->pb) - 1) / st->codec->channels; |
| else |
| st->duration = avio_rb32(s->pb) * 16 / st->codec->channels; |
| size -= 56; |
| found_shdr = 1; |
| break; |
| case MKTAG('S','H','D','R'): |
| if (size > 0x78) { |
| avio_skip(s->pb, 0x74); |
| size -= 0x78; |
| if (avio_rl32(s->pb) == MKTAG('C','T','R','L') && size > 4) { |
| ctrl_size = avio_rb32(s->pb); |
| size -= 4; |
| } |
| } |
| break; |
| default: |
| av_log(s, AV_LOG_DEBUG, "skipping unknown chunk: %X\n", chunk); |
| break; |
| } |
| |
| avio_skip(s->pb, size); |
| } |
| |
| switch (codec) { |
| case MKTAG('S','D','X','2'): |
| st->codec->codec_id = AV_CODEC_ID_SDX2_DPCM; |
| st->codec->block_align = 1 * st->codec->channels; |
| break; |
| default: |
| avpriv_request_sample(s, "codec %X", codec); |
| return AVERROR_PATCHWELCOME; |
| } |
| |
| avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); |
| |
| return 0; |
| } |
| |
| static int threedostr_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| unsigned chunk, size, found_ssmp = 0; |
| AVStream *st = s->streams[0]; |
| int64_t pos; |
| int ret = 0; |
| |
| while (!found_ssmp) { |
| if (avio_feof(s->pb)) |
| return AVERROR_EOF; |
| |
| pos = avio_tell(s->pb); |
| chunk = avio_rl32(s->pb); |
| size = avio_rb32(s->pb); |
| |
| if (!size) |
| continue; |
| |
| if (size < 8) |
| return AVERROR_INVALIDDATA; |
| size -= 8; |
| |
| switch (chunk) { |
| case MKTAG('S','N','D','S'): |
| if (size <= 16) |
| return AVERROR_INVALIDDATA; |
| avio_skip(s->pb, 8); |
| if (avio_rl32(s->pb) != MKTAG('S','S','M','P')) |
| return AVERROR_INVALIDDATA; |
| avio_skip(s->pb, 4); |
| size -= 16; |
| ret = av_get_packet(s->pb, pkt, size); |
| pkt->pos = pos; |
| pkt->stream_index = 0; |
| pkt->duration = size / st->codec->channels; |
| size = 0; |
| found_ssmp = 1; |
| break; |
| default: |
| av_log(s, AV_LOG_DEBUG, "skipping unknown chunk: %X\n", chunk); |
| break; |
| } |
| |
| avio_skip(s->pb, size); |
| } |
| |
| return ret; |
| } |
| |
| AVInputFormat ff_threedostr_demuxer = { |
| .name = "3dostr", |
| .long_name = NULL_IF_CONFIG_SMALL("3DO STR"), |
| .read_probe = threedostr_probe, |
| .read_header = threedostr_read_header, |
| .read_packet = threedostr_read_packet, |
| .extensions = "str", |
| .flags = AVFMT_GENERIC_INDEX, |
| }; |