/* * ISS (.iss) file demuxer * Copyright (c) 2008 Jaikrishnan Menon <realityman@gmx.net> * * 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 */ /** * @file * Funcom ISS file demuxer * @author Jaikrishnan Menon * @see http://wiki.multimedia.cx/index.php?title=FunCom_ISS */ #include "libavutil/channel_layout.h" #include "avformat.h" #include "demux.h" #include "internal.h" #include "libavutil/avstring.h" #define ISS_SIG "IMA_ADPCM_Sound" #define ISS_SIG_LEN 15 #define MAX_TOKEN_SIZE 20 typedef struct IssDemuxContext { 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(const 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) { 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 if (sscanf(token, "%d", &iss->packet_size) != 1) { av_log(s, AV_LOG_ERROR, "Failed parsing packet size\n"); return AVERROR_INVALIDDATA; } get_token(pb, token, sizeof(token)); //File ID get_token(pb, token, sizeof(token)); //out size get_token(pb, token, sizeof(token)); //stereo if (sscanf(token, "%d", &stereo) != 1) { av_log(s, AV_LOG_ERROR, "Failed parsing stereo flag\n"); return AVERROR_INVALIDDATA; } get_token(pb, token, sizeof(token)); //Unknown1 get_token(pb, token, sizeof(token)); //RateDivisor if (sscanf(token, "%d", &rate_divisor) != 1) { av_log(s, AV_LOG_ERROR, "Failed parsing rate_divisor\n"); return AVERROR_INVALIDDATA; } get_token(pb, token, sizeof(token)); //Unknown2 get_token(pb, token, sizeof(token)); //Version ID get_token(pb, token, sizeof(token)); //Size if (iss->packet_size <= 0) { av_log(s, AV_LOG_ERROR, "packet_size %d is invalid\n", iss->packet_size); return AVERROR_INVALIDDATA; } iss->sample_start_pos = avio_tell(pb); st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; st->codecpar->codec_id = AV_CODEC_ID_ADPCM_IMA_ISS; if (stereo) { st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO; } else { st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO; } st->codecpar->sample_rate = 44100; if(rate_divisor > 0) st->codecpar->sample_rate /= rate_divisor; st->codecpar->bits_per_coded_sample = 4; st->codecpar->bit_rate = st->codecpar->ch_layout.nb_channels * st->codecpar->sample_rate * st->codecpar->bits_per_coded_sample; st->codecpar->block_align = iss->packet_size; avpriv_set_pts_info(st, 32, 1, st->codecpar->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]->codecpar->ch_layout.nb_channels > 0) pkt->pts /= s->streams[0]->codecpar->ch_layout.nb_channels * 2; return 0; } const FFInputFormat ff_iss_demuxer = { .p.name = "iss", .p.long_name = NULL_IF_CONFIG_SMALL("Funcom ISS"), .priv_data_size = sizeof(IssDemuxContext), .read_probe = iss_probe, .read_header = iss_read_header, .read_packet = iss_read_packet, };