1/* 2 * ADP demuxer 3 * Copyright (c) 2013 James Almer 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 "libavutil/intreadwrite.h" 24#include "avformat.h" 25#include "internal.h" 26 27static int adp_probe(AVProbeData *p) 28{ 29 int i, changes = 0; 30 char last = 0; 31 32 if (p->buf_size < 32) 33 return 0; 34 35 for (i = 0; i < p->buf_size - 3; i+=32) { 36 if (p->buf[i] != p->buf[i+2] || p->buf[i+1] != p->buf[i+3]) 37 return 0; 38 if (p->buf[i] != last) 39 changes++; 40 last = p->buf[i]; 41 } 42 if (changes <= 1) 43 return 0; 44 45 return p->buf_size < 260 ? 1 : AVPROBE_SCORE_MAX / 4; 46} 47 48static int adp_read_header(AVFormatContext *s) 49{ 50 AVStream *st; 51 52 st = avformat_new_stream(s, NULL); 53 if (!st) 54 return AVERROR(ENOMEM); 55 56 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 57 st->codec->codec_id = AV_CODEC_ID_ADPCM_DTK; 58 st->codec->channel_layout = AV_CH_LAYOUT_STEREO; 59 st->codec->channels = 2; 60 st->codec->sample_rate = 48000; 61 st->start_time = 0; 62 if (s->pb->seekable) 63 st->duration = av_get_audio_frame_duration(st->codec, avio_size(s->pb)); 64 65 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); 66 67 return 0; 68} 69 70static int adp_read_packet(AVFormatContext *s, AVPacket *pkt) 71{ 72 int ret, size = 1024; 73 74 if (url_feof(s->pb)) 75 return AVERROR_EOF; 76 77 ret = av_get_packet(s->pb, pkt, size); 78 79 if (ret != size) { 80 if (ret < 0) { 81 av_free_packet(pkt); 82 return ret; 83 } 84 av_shrink_packet(pkt, ret); 85 } 86 pkt->stream_index = 0; 87 88 return ret; 89} 90 91AVInputFormat ff_adp_demuxer = { 92 .name = "adp", 93 .long_name = NULL_IF_CONFIG_SMALL("ADP"), 94 .read_probe = adp_probe, 95 .read_header = adp_read_header, 96 .read_packet = adp_read_packet, 97 .extensions = "adp,dtk", 98}; 99