1/* 2 * AFC demuxer 3 * Copyright (c) 2012 Paul B Mahol 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/channel_layout.h" 23#include "avformat.h" 24#include "internal.h" 25 26typedef struct AFCDemuxContext { 27 int64_t data_end; 28} AFCDemuxContext; 29 30static int afc_read_header(AVFormatContext *s) 31{ 32 AFCDemuxContext *c = s->priv_data; 33 AVStream *st; 34 35 st = avformat_new_stream(s, NULL); 36 if (!st) 37 return AVERROR(ENOMEM); 38 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 39 st->codec->codec_id = AV_CODEC_ID_ADPCM_AFC; 40 st->codec->channels = 2; 41 st->codec->channel_layout = AV_CH_LAYOUT_STEREO; 42 43 if (ff_alloc_extradata(st->codec, 1)) 44 return AVERROR(ENOMEM); 45 st->codec->extradata[0] = 8 * st->codec->channels; 46 47 c->data_end = avio_rb32(s->pb) + 32LL; 48 st->duration = avio_rb32(s->pb); 49 st->codec->sample_rate = avio_rb16(s->pb); 50 avio_skip(s->pb, 22); 51 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); 52 53 return 0; 54} 55 56static int afc_read_packet(AVFormatContext *s, AVPacket *pkt) 57{ 58 AFCDemuxContext *c = s->priv_data; 59 int64_t size; 60 int ret; 61 62 size = FFMIN(c->data_end - avio_tell(s->pb), 18 * 128); 63 if (size <= 0) 64 return AVERROR_EOF; 65 66 ret = av_get_packet(s->pb, pkt, size); 67 pkt->stream_index = 0; 68 return ret; 69} 70 71AVInputFormat ff_afc_demuxer = { 72 .name = "afc", 73 .long_name = NULL_IF_CONFIG_SMALL("AFC"), 74 .priv_data_size = sizeof(AFCDemuxContext), 75 .read_header = afc_read_header, 76 .read_packet = afc_read_packet, 77 .extensions = "afc", 78 .flags = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK, 79}; 80