yading@11: /* yading@11: * ISS (.iss) file demuxer yading@11: * Copyright (c) 2008 Jaikrishnan Menon yading@11: * yading@11: * This file is part of FFmpeg. yading@11: * yading@11: * FFmpeg is free software; you can redistribute it and/or yading@11: * modify it under the terms of the GNU Lesser General Public yading@11: * License as published by the Free Software Foundation; either yading@11: * version 2.1 of the License, or (at your option) any later version. yading@11: * yading@11: * FFmpeg is distributed in the hope that it will be useful, yading@11: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@11: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@11: * Lesser General Public License for more details. yading@11: * yading@11: * You should have received a copy of the GNU Lesser General Public yading@11: * License along with FFmpeg; if not, write to the Free Software yading@11: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@11: */ yading@11: yading@11: /** yading@11: * @file yading@11: * Funcom ISS file demuxer yading@11: * @author Jaikrishnan Menon yading@11: * @see http://wiki.multimedia.cx/index.php?title=FunCom_ISS yading@11: */ yading@11: yading@11: #include "libavutil/channel_layout.h" yading@11: #include "avformat.h" yading@11: #include "internal.h" yading@11: #include "libavutil/avstring.h" yading@11: yading@11: #define ISS_SIG "IMA_ADPCM_Sound" yading@11: #define ISS_SIG_LEN 15 yading@11: #define MAX_TOKEN_SIZE 20 yading@11: yading@11: typedef struct { yading@11: int packet_size; yading@11: int sample_start_pos; yading@11: } IssDemuxContext; yading@11: yading@11: static void get_token(AVIOContext *s, char *buf, int maxlen) yading@11: { yading@11: int i = 0; yading@11: char c; yading@11: yading@11: while ((c = avio_r8(s))) { yading@11: if(c == ' ') yading@11: break; yading@11: if (i < maxlen-1) yading@11: buf[i++] = c; yading@11: } yading@11: yading@11: if(!c) yading@11: avio_r8(s); yading@11: yading@11: buf[i] = 0; /* Ensure null terminated, but may be truncated */ yading@11: } yading@11: yading@11: static int iss_probe(AVProbeData *p) yading@11: { yading@11: if (strncmp(p->buf, ISS_SIG, ISS_SIG_LEN)) yading@11: return 0; yading@11: yading@11: return AVPROBE_SCORE_MAX; yading@11: } yading@11: yading@11: static av_cold int iss_read_header(AVFormatContext *s) yading@11: { yading@11: IssDemuxContext *iss = s->priv_data; yading@11: AVIOContext *pb = s->pb; yading@11: AVStream *st; yading@11: char token[MAX_TOKEN_SIZE]; yading@11: int stereo, rate_divisor; yading@11: yading@11: get_token(pb, token, sizeof(token)); //"IMA_ADPCM_Sound" yading@11: get_token(pb, token, sizeof(token)); //packet size yading@11: sscanf(token, "%d", &iss->packet_size); yading@11: get_token(pb, token, sizeof(token)); //File ID yading@11: get_token(pb, token, sizeof(token)); //out size yading@11: get_token(pb, token, sizeof(token)); //stereo yading@11: sscanf(token, "%d", &stereo); yading@11: get_token(pb, token, sizeof(token)); //Unknown1 yading@11: get_token(pb, token, sizeof(token)); //RateDivisor yading@11: sscanf(token, "%d", &rate_divisor); yading@11: get_token(pb, token, sizeof(token)); //Unknown2 yading@11: get_token(pb, token, sizeof(token)); //Version ID yading@11: get_token(pb, token, sizeof(token)); //Size yading@11: yading@11: if (iss->packet_size <= 0) { yading@11: av_log(s, AV_LOG_ERROR, "packet_size %d is invalid\n", iss->packet_size); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: yading@11: iss->sample_start_pos = avio_tell(pb); yading@11: yading@11: st = avformat_new_stream(s, NULL); yading@11: if (!st) yading@11: return AVERROR(ENOMEM); yading@11: st->codec->codec_type = AVMEDIA_TYPE_AUDIO; yading@11: st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_ISS; yading@11: if (stereo) { yading@11: st->codec->channels = 2; yading@11: st->codec->channel_layout = AV_CH_LAYOUT_STEREO; yading@11: } else { yading@11: st->codec->channels = 1; yading@11: st->codec->channel_layout = AV_CH_LAYOUT_MONO; yading@11: } yading@11: st->codec->sample_rate = 44100; yading@11: if(rate_divisor > 0) yading@11: st->codec->sample_rate /= rate_divisor; yading@11: st->codec->bits_per_coded_sample = 4; yading@11: st->codec->bit_rate = st->codec->channels * st->codec->sample_rate yading@11: * st->codec->bits_per_coded_sample; yading@11: st->codec->block_align = iss->packet_size; yading@11: avpriv_set_pts_info(st, 32, 1, st->codec->sample_rate); yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: static int iss_read_packet(AVFormatContext *s, AVPacket *pkt) yading@11: { yading@11: IssDemuxContext *iss = s->priv_data; yading@11: int ret = av_get_packet(s->pb, pkt, iss->packet_size); yading@11: yading@11: if(ret != iss->packet_size) yading@11: return AVERROR(EIO); yading@11: yading@11: pkt->stream_index = 0; yading@11: pkt->pts = avio_tell(s->pb) - iss->sample_start_pos; yading@11: if(s->streams[0]->codec->channels > 0) yading@11: pkt->pts /= s->streams[0]->codec->channels*2; yading@11: return 0; yading@11: } yading@11: yading@11: AVInputFormat ff_iss_demuxer = { yading@11: .name = "iss", yading@11: .long_name = NULL_IF_CONFIG_SMALL("Funcom ISS"), yading@11: .priv_data_size = sizeof(IssDemuxContext), yading@11: .read_probe = iss_probe, yading@11: .read_header = iss_read_header, yading@11: .read_packet = iss_read_packet, yading@11: };