libavformat/oma.c

Go to the documentation of this file.
00001 /*
00002  * Sony OpenMG (OMA) demuxer
00003  *
00004  * Copyright (c) 2008 Maxim Poliakovski
00005  * 2008 Benjamin Larsson
00006  *
00007  * This file is part of FFmpeg.
00008  *
00009  * FFmpeg is free software; you can redistribute it and/or
00010  * modify it under the terms of the GNU Lesser General Public
00011  * License as published by the Free Software Foundation; either
00012  * version 2.1 of the License, or (at your option) any later version.
00013  *
00014  * FFmpeg is distributed in the hope that it will be useful,
00015  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
00017  * Lesser General Public License for more details.
00018  *
00019  * You should have received a copy of the GNU Lesser General Public
00020  * License along with FFmpeg; if not, write to the Free Software
00021  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00022  */
00023 
00045 #include "avformat.h"
00046 #include "libavutil/intreadwrite.h"
00047 #include "raw.h"
00048 #include "riff.h"
00049 
00050 #define EA3_HEADER_SIZE 96
00051 
00052 enum {
00053 OMA_CODECID_ATRAC3 = 0,
00054 OMA_CODECID_ATRAC3P = 1,
00055 OMA_CODECID_MP3 = 3,
00056 OMA_CODECID_LPCM = 4,
00057 OMA_CODECID_WMA = 5,
00058 };
00059 
00060 static const AVCodecTag codec_oma_tags[] = {
00061 { CODEC_ID_ATRAC3, OMA_CODECID_ATRAC3 },
00062 { CODEC_ID_ATRAC3P, OMA_CODECID_ATRAC3P },
00063 { CODEC_ID_MP3, OMA_CODECID_MP3 },
00064 };
00065 
00066 static int oma_read_header(AVFormatContext *s,
00067 AVFormatParameters *ap)
00068 {
00069 static const uint16_t srate_tab[6] = {320,441,480,882,960,0};
00070 int ret, ea3_taglen, EA3_pos, framesize, jsflag, samplerate;
00071 uint32_t codec_params;
00072 int16_t eid;
00073 uint8_t buf[EA3_HEADER_SIZE];
00074 uint8_t *edata;
00075 AVStream *st;
00076 
00077 ret = get_buffer(s->pb, buf, 10);
00078 if (ret != 10)
00079 return -1;
00080 
00081 ea3_taglen = ((buf[6] & 0x7f) << 21) | ((buf[7] & 0x7f) << 14) | ((buf[8] & 0x7f) << 7) | (buf[9] & 0x7f);
00082 
00083 EA3_pos = ea3_taglen + 10;
00084 if (buf[5] & 0x10)
00085 EA3_pos += 10;
00086 
00087 url_fseek(s->pb, EA3_pos, SEEK_SET);
00088 ret = get_buffer(s->pb, buf, EA3_HEADER_SIZE);
00089 if (ret != EA3_HEADER_SIZE)
00090 return -1;
00091 
00092 if (memcmp(buf, (const uint8_t[]){'E', 'A', '3'},3) || buf[4] != 0 || buf[5] != EA3_HEADER_SIZE) {
00093 av_log(s, AV_LOG_ERROR, "Couldn't find the EA3 header !\n");
00094 return -1;
00095 }
00096 
00097 eid = AV_RB16(&buf[6]);
00098 if (eid != -1 && eid != -128) {
00099 av_log(s, AV_LOG_ERROR, "Encrypted file! Eid: %d\n", eid);
00100 return -1;
00101 }
00102 
00103 codec_params = AV_RB24(&buf[33]);
00104 
00105 st = av_new_stream(s, 0);
00106 if (!st)
00107 return AVERROR(ENOMEM);
00108 
00109 st->start_time = 0;
00110 st->codec->codec_type = CODEC_TYPE_AUDIO;
00111 st->codec->codec_tag = buf[32];
00112 st->codec->codec_id = codec_get_id(codec_oma_tags, st->codec->codec_tag);
00113 
00114 switch (buf[32]) {
00115 case OMA_CODECID_ATRAC3:
00116 samplerate = srate_tab[(codec_params >> 13) & 7]*100;
00117 if (samplerate != 44100)
00118 av_log(s, AV_LOG_ERROR, "Unsupported sample rate, send sample file to developers: %d\n", samplerate);
00119 
00120 framesize = (codec_params & 0x3FF) * 8;
00121 jsflag = (codec_params >> 17) & 1; /* get stereo coding mode, 1 for joint-stereo */
00122 st->codec->channels = 2;
00123 st->codec->sample_rate = samplerate;
00124 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
00125 
00126 /* fake the atrac3 extradata (wav format, makes stream copy to wav work) */
00127 st->codec->extradata_size = 14;
00128 edata = av_mallocz(14 + FF_INPUT_BUFFER_PADDING_SIZE);
00129 if (!edata)
00130 return AVERROR(ENOMEM);
00131 
00132 st->codec->extradata = edata;
00133 AV_WL16(&edata[0], 1); // always 1
00134 AV_WL32(&edata[2], samplerate); // samples rate
00135 AV_WL16(&edata[6], jsflag); // coding mode
00136 AV_WL16(&edata[8], jsflag); // coding mode
00137 AV_WL16(&edata[10], 1); // always 1
00138 // AV_WL16(&edata[12], 0); // always 0
00139 
00140 av_set_pts_info(st, 64, 1, st->codec->sample_rate);
00141 break;
00142 case OMA_CODECID_ATRAC3P:
00143 st->codec->channels = (codec_params >> 10) & 7;
00144 framesize = ((codec_params & 0x3FF) * 8) + 8;
00145 st->codec->sample_rate = srate_tab[(codec_params >> 13) & 7]*100;
00146 st->codec->bit_rate = st->codec->sample_rate * framesize * 8 / 1024;
00147 av_set_pts_info(st, 64, 1, st->codec->sample_rate);
00148 av_log(s, AV_LOG_ERROR, "Unsupported codec ATRAC3+!\n");
00149 break;
00150 case OMA_CODECID_MP3:
00151 st->need_parsing = AVSTREAM_PARSE_FULL;
00152 framesize = 1024;
00153 break;
00154 default:
00155 av_log(s, AV_LOG_ERROR, "Unsupported codec %d!\n",buf[32]);
00156 return -1;
00157 break;
00158 }
00159 
00160 st->codec->block_align = framesize;
00161 url_fseek(s->pb, EA3_pos + EA3_HEADER_SIZE, SEEK_SET);
00162 
00163 return 0;
00164 }
00165 
00166 
00167 static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
00168 {
00169 int ret = av_get_packet(s->pb, pkt, s->streams[0]->codec->block_align);
00170 
00171 pkt->stream_index = 0;
00172 if (ret <= 0)
00173 return AVERROR(EIO);
00174 
00175 return ret;
00176 }
00177 
00178 static int oma_read_probe(AVProbeData *p)
00179 {
00180 if (!memcmp(p->buf, (const uint8_t[]){'e', 'a', '3', 3, 0},5))
00181 return AVPROBE_SCORE_MAX;
00182 else
00183 return 0;
00184 }
00185 
00186 
00187 AVInputFormat oma_demuxer = {
00188 "oma",
00189 NULL_IF_CONFIG_SMALL("Sony OpenMG audio"),
00190 0,
00191 oma_read_probe,
00192 oma_read_header,
00193 oma_read_packet,
00194 0,
00195 pcm_read_seek,
00196 .flags= AVFMT_GENERIC_INDEX,
00197 .extensions = "oma,aa3",
00198 .codec_tag= (const AVCodecTag* const []){codec_oma_tags, 0},
00199 };
00200 

Generated on Fri Oct 26 02:35:41 2012 for FFmpeg by doxygen 1.5.8

AltStyle によって変換されたページ (->オリジナル) /