libavformat/vqf.c
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00001 /*
00002  * VQF demuxer
00003  * Copyright (c) 2009 Vitor Sessak
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 #include "avformat.h"
00023 #include "internal.h"
00024 #include "libavutil/intreadwrite.h"
00025 #include "libavutil/dict.h"
00026 #include "libavutil/mathematics.h"
00027 #include "riff.h"
00028 
00029 typedef struct VqfContext {
00030     int frame_bit_len;
00031     uint8_t last_frame_bits;
00032     int remaining_bits;
00033 } VqfContext;
00034 
00035 static int vqf_probe(AVProbeData *probe_packet)
00036 {
00037     if (AV_RL32(probe_packet->buf) != MKTAG('T','W','I','N'))
00038         return 0;
00039 
00040     if (!memcmp(probe_packet->buf + 4, "97012000", 8))
00041         return AVPROBE_SCORE_MAX;
00042 
00043     if (!memcmp(probe_packet->buf + 4, "00052200", 8))
00044         return AVPROBE_SCORE_MAX;
00045 
00046     return AVPROBE_SCORE_MAX/2;
00047 }
00048 
00049 static void add_metadata(AVFormatContext *s, uint32_t tag,
00050                          unsigned int tag_len, unsigned int remaining)
00051 {
00052     int len = FFMIN(tag_len, remaining);
00053     char *buf, key[5] = {0};
00054 
00055     if (len == UINT_MAX)
00056         return;
00057 
00058     buf = av_malloc(len+1);
00059     if (!buf)
00060         return;
00061     avio_read(s->pb, buf, len);
00062     buf[len] = 0;
00063     AV_WL32(key, tag);
00064     av_dict_set(&s->metadata, key, buf, AV_DICT_DONT_STRDUP_VAL);
00065 }
00066 
00067 static const AVMetadataConv vqf_metadata_conv[] = {
00068     { "(c) ", "copyright" },
00069     { "ARNG", "arranger"  },
00070     { "AUTH", "author"    },
00071     { "BAND", "band"      },
00072     { "CDCT", "conductor" },
00073     { "COMT", "comment"   },
00074     { "FILE", "filename"  },
00075     { "GENR", "genre"     },
00076     { "LABL", "publisher" },
00077     { "MUSC", "composer"  },
00078     { "NAME", "title"     },
00079     { "NOTE", "note"      },
00080     { "PROD", "producer"  },
00081     { "PRSN", "personnel" },
00082     { "REMX", "remixer"   },
00083     { "SING", "singer"    },
00084     { "TRCK", "track"     },
00085     { "WORD", "words"     },
00086     { 0 },
00087 };
00088 
00089 static int vqf_read_header(AVFormatContext *s, AVFormatParameters *ap)
00090 {
00091     VqfContext *c = s->priv_data;
00092     AVStream *st  = avformat_new_stream(s, NULL);
00093     int chunk_tag;
00094     int rate_flag = -1;
00095     int header_size;
00096     int read_bitrate = 0;
00097     int size;
00098     uint8_t comm_chunk[12];
00099 
00100     if (!st)
00101         return AVERROR(ENOMEM);
00102 
00103     avio_skip(s->pb, 12);
00104 
00105     header_size = avio_rb32(s->pb);
00106 
00107     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00108     st->codec->codec_id   = CODEC_ID_TWINVQ;
00109     st->start_time = 0;
00110 
00111     do {
00112         int len;
00113         chunk_tag = avio_rl32(s->pb);
00114 
00115         if (chunk_tag == MKTAG('D','A','T','A'))
00116             break;
00117 
00118         len = avio_rb32(s->pb);
00119 
00120         if ((unsigned) len > INT_MAX/2) {
00121             av_log(s, AV_LOG_ERROR, "Malformed header\n");
00122             return -1;
00123         }
00124 
00125         header_size -= 8;
00126 
00127         switch(chunk_tag){
00128         case MKTAG('C','O','M','M'):
00129             avio_read(s->pb, comm_chunk, 12);
00130             st->codec->channels = AV_RB32(comm_chunk    ) + 1;
00131             read_bitrate        = AV_RB32(comm_chunk + 4);
00132             rate_flag           = AV_RB32(comm_chunk + 8);
00133             avio_skip(s->pb, len-12);
00134 
00135             st->codec->bit_rate              = read_bitrate*1000;
00136             break;
00137         case MKTAG('D','S','I','Z'): // size of compressed data
00138         {
00139             char buf[8] = {0};
00140             int size = avio_rb32(s->pb);
00141 
00142             snprintf(buf, sizeof(buf), "%d", size);
00143             av_dict_set(&s->metadata, "size", buf, 0);
00144         }
00145             break;
00146         case MKTAG('Y','E','A','R'): // recording date
00147         case MKTAG('E','N','C','D'): // compression date
00148         case MKTAG('E','X','T','R'): // reserved
00149         case MKTAG('_','Y','M','H'): // reserved
00150         case MKTAG('_','N','T','T'): // reserved
00151         case MKTAG('_','I','D','3'): // reserved for ID3 tags
00152             avio_skip(s->pb, FFMIN(len, header_size));
00153             break;
00154         default:
00155             add_metadata(s, chunk_tag, len, header_size);
00156             break;
00157         }
00158 
00159         header_size -= len;
00160 
00161     } while (header_size >= 0);
00162 
00163     switch (rate_flag) {
00164     case -1:
00165         av_log(s, AV_LOG_ERROR, "COMM tag not found!\n");
00166         return -1;
00167     case 44:
00168         st->codec->sample_rate = 44100;
00169         break;
00170     case 22:
00171         st->codec->sample_rate = 22050;
00172         break;
00173     case 11:
00174         st->codec->sample_rate = 11025;
00175         break;
00176     default:
00177         if (rate_flag < 8 || rate_flag > 44) {
00178             av_log(s, AV_LOG_ERROR, "Invalid rate flag %d\n", rate_flag);
00179             return AVERROR_INVALIDDATA;
00180         }
00181         st->codec->sample_rate = rate_flag*1000;
00182         break;
00183     }
00184 
00185     if (read_bitrate / st->codec->channels <  8 ||
00186         read_bitrate / st->codec->channels > 48) {
00187         av_log(s, AV_LOG_ERROR, "Invalid bitrate per channel %d\n",
00188                read_bitrate / st->codec->channels);
00189         return AVERROR_INVALIDDATA;
00190     }
00191 
00192     switch (((st->codec->sample_rate/1000) << 8) +
00193             read_bitrate/st->codec->channels) {
00194     case (11<<8) + 8 :
00195     case (8 <<8) + 8 :
00196     case (11<<8) + 10:
00197     case (22<<8) + 32:
00198         size = 512;
00199         break;
00200     case (16<<8) + 16:
00201     case (22<<8) + 20:
00202     case (22<<8) + 24:
00203         size = 1024;
00204         break;
00205     case (44<<8) + 40:
00206     case (44<<8) + 48:
00207         size = 2048;
00208         break;
00209     default:
00210         av_log(s, AV_LOG_ERROR, "Mode not suported: %d Hz, %d kb/s.\n",
00211                st->codec->sample_rate, st->codec->bit_rate);
00212         return -1;
00213     }
00214     c->frame_bit_len = st->codec->bit_rate*size/st->codec->sample_rate;
00215     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00216 
00217     /* put first 12 bytes of COMM chunk in extradata */
00218     if (!(st->codec->extradata = av_malloc(12 + FF_INPUT_BUFFER_PADDING_SIZE)))
00219         return AVERROR(ENOMEM);
00220     st->codec->extradata_size = 12;
00221     memcpy(st->codec->extradata, comm_chunk, 12);
00222 
00223     ff_metadata_conv_ctx(s, NULL, vqf_metadata_conv);
00224 
00225     return 0;
00226 }
00227 
00228 static int vqf_read_packet(AVFormatContext *s, AVPacket *pkt)
00229 {
00230     VqfContext *c = s->priv_data;
00231     int ret;
00232     int size = (c->frame_bit_len - c->remaining_bits + 7)>>3;
00233 
00234     pkt->pos          = avio_tell(s->pb);
00235     pkt->stream_index = 0;
00236 
00237     if (av_new_packet(pkt, size+2) < 0)
00238         return AVERROR(EIO);
00239 
00240     pkt->data[0] = 8 - c->remaining_bits; // Number of bits to skip
00241     pkt->data[1] = c->last_frame_bits;
00242     ret = avio_read(s->pb, pkt->data+2, size);
00243 
00244     if (ret<=0) {
00245         av_free_packet(pkt);
00246         return AVERROR(EIO);
00247     }
00248 
00249     c->last_frame_bits = pkt->data[size+1];
00250     c->remaining_bits  = (size << 3) - c->frame_bit_len + c->remaining_bits;
00251 
00252     return size+2;
00253 }
00254 
00255 static int vqf_read_seek(AVFormatContext *s,
00256                          int stream_index, int64_t timestamp, int flags)
00257 {
00258     VqfContext *c = s->priv_data;
00259     AVStream *st;
00260     int ret;
00261     int64_t pos;
00262 
00263     st = s->streams[stream_index];
00264     pos = av_rescale_rnd(timestamp * st->codec->bit_rate,
00265                          st->time_base.num,
00266                          st->time_base.den * (int64_t)c->frame_bit_len,
00267                          (flags & AVSEEK_FLAG_BACKWARD) ?
00268                                                    AV_ROUND_DOWN : AV_ROUND_UP);
00269     pos *= c->frame_bit_len;
00270 
00271     st->cur_dts = av_rescale(pos, st->time_base.den,
00272                              st->codec->bit_rate * (int64_t)st->time_base.num);
00273 
00274     if ((ret = avio_seek(s->pb, ((pos-7) >> 3) + s->data_offset, SEEK_SET)) < 0)
00275         return ret;
00276 
00277     c->remaining_bits = -7 - ((pos-7)&7);
00278     return 0;
00279 }
00280 
00281 AVInputFormat ff_vqf_demuxer = {
00282     .name           = "vqf",
00283     .long_name      = NULL_IF_CONFIG_SMALL("Nippon Telegraph and Telephone Corporation (NTT) TwinVQ"),
00284     .priv_data_size = sizeof(VqfContext),
00285     .read_probe     = vqf_probe,
00286     .read_header    = vqf_read_header,
00287     .read_packet    = vqf_read_packet,
00288     .read_seek      = vqf_read_seek,
00289     .extensions     = "vqf,vql,vqe",
00290 };