Libav 0.7.1
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00001 /* 00002 * Sierra SOL demuxer 00003 * Copyright Konstantin Shishkov 00004 * 00005 * This file is part of Libav. 00006 * 00007 * Libav is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * Libav is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with Libav; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00022 /* 00023 * Based on documents from Game Audio Player and own research 00024 */ 00025 00026 #include "libavutil/bswap.h" 00027 #include "avformat.h" 00028 #include "pcm.h" 00029 00030 /* if we don't know the size in advance */ 00031 #define AU_UNKNOWN_SIZE ((uint32_t)(~0)) 00032 00033 static int sol_probe(AVProbeData *p) 00034 { 00035 /* check file header */ 00036 uint16_t magic; 00037 magic=av_le2ne16(*((uint16_t*)p->buf)); 00038 if ((magic == 0x0B8D || magic == 0x0C0D || magic == 0x0C8D) && 00039 p->buf[2] == 'S' && p->buf[3] == 'O' && 00040 p->buf[4] == 'L' && p->buf[5] == 0) 00041 return AVPROBE_SCORE_MAX; 00042 else 00043 return 0; 00044 } 00045 00046 #define SOL_DPCM 1 00047 #define SOL_16BIT 4 00048 #define SOL_STEREO 16 00049 00050 static enum CodecID sol_codec_id(int magic, int type) 00051 { 00052 if (magic == 0x0B8D) 00053 { 00054 if (type & SOL_DPCM) return CODEC_ID_SOL_DPCM; 00055 else return CODEC_ID_PCM_U8; 00056 } 00057 if (type & SOL_DPCM) 00058 { 00059 if (type & SOL_16BIT) return CODEC_ID_SOL_DPCM; 00060 else if (magic == 0x0C8D) return CODEC_ID_SOL_DPCM; 00061 else return CODEC_ID_SOL_DPCM; 00062 } 00063 if (type & SOL_16BIT) return CODEC_ID_PCM_S16LE; 00064 return CODEC_ID_PCM_U8; 00065 } 00066 00067 static int sol_codec_type(int magic, int type) 00068 { 00069 if (magic == 0x0B8D) return 1;//SOL_DPCM_OLD; 00070 if (type & SOL_DPCM) 00071 { 00072 if (type & SOL_16BIT) return 3;//SOL_DPCM_NEW16; 00073 else if (magic == 0x0C8D) return 1;//SOL_DPCM_OLD; 00074 else return 2;//SOL_DPCM_NEW8; 00075 } 00076 return -1; 00077 } 00078 00079 static int sol_channels(int magic, int type) 00080 { 00081 if (magic == 0x0B8D || !(type & SOL_STEREO)) return 1; 00082 return 2; 00083 } 00084 00085 static int sol_read_header(AVFormatContext *s, 00086 AVFormatParameters *ap) 00087 { 00088 unsigned int magic,tag; 00089 AVIOContext *pb = s->pb; 00090 unsigned int id, channels, rate, type; 00091 enum CodecID codec; 00092 AVStream *st; 00093 00094 /* check ".snd" header */ 00095 magic = avio_rl16(pb); 00096 tag = avio_rl32(pb); 00097 if (tag != MKTAG('S', 'O', 'L', 0)) 00098 return -1; 00099 rate = avio_rl16(pb); 00100 type = avio_r8(pb); 00101 avio_skip(pb, 4); /* size */ 00102 if (magic != 0x0B8D) 00103 avio_r8(pb); /* newer SOLs contain padding byte */ 00104 00105 codec = sol_codec_id(magic, type); 00106 channels = sol_channels(magic, type); 00107 00108 if (codec == CODEC_ID_SOL_DPCM) 00109 id = sol_codec_type(magic, type); 00110 else id = 0; 00111 00112 /* now we are ready: build format streams */ 00113 st = av_new_stream(s, 0); 00114 if (!st) 00115 return -1; 00116 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 00117 st->codec->codec_tag = id; 00118 st->codec->codec_id = codec; 00119 st->codec->channels = channels; 00120 st->codec->sample_rate = rate; 00121 av_set_pts_info(st, 64, 1, rate); 00122 return 0; 00123 } 00124 00125 #define MAX_SIZE 4096 00126 00127 static int sol_read_packet(AVFormatContext *s, 00128 AVPacket *pkt) 00129 { 00130 int ret; 00131 00132 if (s->pb->eof_reached) 00133 return AVERROR(EIO); 00134 ret= av_get_packet(s->pb, pkt, MAX_SIZE); 00135 if (ret < 0) 00136 return ret; 00137 pkt->stream_index = 0; 00138 00139 /* note: we need to modify the packet size here to handle the last 00140 packet */ 00141 pkt->size = ret; 00142 return 0; 00143 } 00144 00145 AVInputFormat ff_sol_demuxer = { 00146 "sol", 00147 NULL_IF_CONFIG_SMALL("Sierra SOL format"), 00148 0, 00149 sol_probe, 00150 sol_read_header, 00151 sol_read_packet, 00152 NULL, 00153 pcm_read_seek, 00154 };