/* * ISS (.iss) file demuxer * Copyright (c) 2008 Jaikrishnan Menon <realityman@gmx.net> * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Funcom ISS file demuxer * @author Jaikrishnan Menon * for more information on the .iss file format, visit: * http://wiki.multimedia.cx/index.php?title=FunCom_ISS */ #include "avformat.h" #include "libavutil/avstring.h" #define ISS_SIG "IMA_ADPCM_Sound" #define ISS_SIG_LEN 15 #define MAX_TOKEN_SIZE 20 typedef struct { int packet_size; int sample_start_pos; } IssDemuxContext; static void get_token(AVIOContext *s, char *buf, int maxlen) { int i = 0; char c; while ((c = avio_r8(s))) { if(c == ' ') break; if (i < maxlen-1) buf[i++] = c; } if(!c) avio_r8(s); buf[i] = 0; /* Ensure null terminated, but may be truncated */ } static int iss_probe(AVProbeData *p) { if (strncmp(p->buf, ISS_SIG, ISS_SIG_LEN)) return 0; return AVPROBE_SCORE_MAX; } static av_cold int iss_read_header(AVFormatContext *s, AVFormatParameters *ap) { IssDemuxContext *iss = s->priv_data; AVIOContext *pb = s->pb; AVStream *st; char token[MAX_TOKEN_SIZE]; int stereo, rate_divisor; get_token(pb, token, sizeof(token)); //"IMA_ADPCM_Sound" get_token(pb, token, sizeof(token)); //packet size sscanf(token, "%d", &iss->packet_size); get_token(pb, token, sizeof(token)); //File ID get_token(pb, token, sizeof(token)); //out size get_token(pb, token, sizeof(token)); //stereo sscanf(token, "%d", &stereo); get_token(pb, token, sizeof(token)); //Unknown1 get_token(pb, token, sizeof(token)); //RateDivisor sscanf(token, "%d", &rate_divisor); get_token(pb, token, sizeof(token)); //Unknown2 get_token(pb, token, sizeof(token)); //Version ID get_token(pb, token, sizeof(token)); //Size iss->sample_start_pos = avio_tell(pb); st = av_new_stream(s, 0); if (!st) return AVERROR(ENOMEM); st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->codec_id = CODEC_ID_ADPCM_IMA_ISS; st->codec->channels = stereo ? 2 : 1; st->codec->sample_rate = 44100; if(rate_divisor > 0) st->codec->sample_rate /= rate_divisor; st->codec->bits_per_coded_sample = 4; st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * st->codec->bits_per_coded_sample; st->codec->block_align = iss->packet_size; av_set_pts_info(st, 32, 1, st->codec->sample_rate); return 0; } static int iss_read_packet(AVFormatContext *s, AVPacket *pkt) { IssDemuxContext *iss = s->priv_data; int ret = av_get_packet(s->pb, pkt, iss->packet_size); if(ret != iss->packet_size) return AVERROR(EIO); pkt->stream_index = 0; pkt->pts = avio_tell(s->pb) - iss->sample_start_pos; if(s->streams[0]->codec->channels > 0) pkt->pts /= s->streams[0]->codec->channels*2; return 0; } AVInputFormat ff_iss_demuxer = { "ISS", NULL_IF_CONFIG_SMALL("Funcom ISS format"), sizeof(IssDemuxContext), iss_probe, iss_read_header, iss_read_packet, };