FFmpeg: libavformat/vqf.c Source File

00001 /*
00002  * VQF demuxer
00003  * Copyright (c) 2009 Vitor Sessak
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 
00028 typedef struct VqfContext {
00029     int frame_bit_len;
00030     uint8_t last_frame_bits;
00031     int remaining_bits;
00032 } VqfContext;
00033 
00034 static int vqf_probe(AVProbeData *probe_packet)
00035 {
00036     if (AV_RL32(probe_packet->buf) != MKTAG('T','W','I','N'))
00037         return 0;
00038 
00039     if (!memcmp(probe_packet->buf + 4, "97012000", 8))
00040         return AVPROBE_SCORE_MAX;
00041 
00042     if (!memcmp(probe_packet->buf + 4, "00052200", 8))
00043         return AVPROBE_SCORE_MAX;
00044 
00045     return AVPROBE_SCORE_MAX/2;
00046 }
00047 
00048 static void add_metadata(AVFormatContext *s, const char *tag,
00049                          unsigned int tag_len, unsigned int remaining)
00050 {
00051     int len = FFMIN(tag_len, remaining);
00052     char *buf;
00053 
00054     if (len == UINT_MAX)
00055         return;
00056 
00057     buf = av_malloc(len+1);
00058     if (!buf)
00059         return;
00060     avio_read(s->pb, buf, len);
00061     buf[len] = 0;
00062     av_dict_set(&s->metadata, tag, buf, AV_DICT_DONT_STRDUP_VAL);
00063 }
00064 
00065 static int vqf_read_header(AVFormatContext *s, AVFormatParameters *ap)
00066 {
00067     VqfContext *c = s->priv_data;
00068     AVStream *st  = avformat_new_stream(s, NULL);
00069     int chunk_tag;
00070     int rate_flag = -1;
00071     int header_size;
00072     int read_bitrate = 0;
00073     int size;
00074     uint8_t comm_chunk[12];
00075 
00076     if (!st)
00077         return AVERROR(ENOMEM);
00078 
00079     avio_skip(s->pb, 12);
00080 
00081     header_size = avio_rb32(s->pb);
00082 
00083     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00084     st->codec->codec_id   = CODEC_ID_TWINVQ;
00085     st->start_time = 0;
00086 
00087     do {
00088         int len;
00089         chunk_tag = avio_rl32(s->pb);
00090 
00091         if (chunk_tag == MKTAG('D','A','T','A'))
00092             break;
00093 
00094         len = avio_rb32(s->pb);
00095 
00096         if ((unsigned) len > INT_MAX/2) {
00097             av_log(s, AV_LOG_ERROR, "Malformed header\n");
00098             return -1;
00099         }
00100 
00101         header_size -= 8;
00102 
00103         switch(chunk_tag){
00104         case MKTAG('C','O','M','M'):
00105             avio_read(s->pb, comm_chunk, 12);
00106             st->codec->channels = AV_RB32(comm_chunk    ) + 1;
00107             read_bitrate        = AV_RB32(comm_chunk + 4);
00108             rate_flag           = AV_RB32(comm_chunk + 8);
00109             avio_skip(s->pb, len-12);
00110 
00111             st->codec->bit_rate              = read_bitrate*1000;
00112             break;
00113         case MKTAG('N','A','M','E'):
00114             add_metadata(s, "title"    , len, header_size);
00115             break;
00116         case MKTAG('(','c',')',' '):
00117             add_metadata(s, "copyright", len, header_size);
00118             break;
00119         case MKTAG('A','U','T','H'):
00120             add_metadata(s, "author"   , len, header_size);
00121             break;
00122         case MKTAG('A','L','B','M'):
00123             add_metadata(s, "album"    , len, header_size);
00124             break;
00125         case MKTAG('T','R','C','K'):
00126             add_metadata(s, "track"    , len, header_size);
00127             break;
00128         case MKTAG('C','O','M','T'):
00129             add_metadata(s, "comment"  , len, header_size);
00130             break;
00131         case MKTAG('F','I','L','E'):
00132             add_metadata(s, "filename" , len, header_size);
00133             break;
00134         case MKTAG('D','S','I','Z'):
00135             add_metadata(s, "size"     , len, header_size);
00136             break;
00137         case MKTAG('D','A','T','E'):
00138             add_metadata(s, "date"     , len, header_size);
00139             break;
00140         case MKTAG('G','E','N','R'):
00141             add_metadata(s, "genre"    , len, header_size);
00142             break;
00143         default:
00144             av_log(s, AV_LOG_ERROR, "Unknown chunk: %c%c%c%c\n",
00145                    ((char*)&chunk_tag)[0], ((char*)&chunk_tag)[1],
00146                    ((char*)&chunk_tag)[2], ((char*)&chunk_tag)[3]);
00147             avio_skip(s->pb, FFMIN(len, header_size));
00148             break;
00149         }
00150 
00151         header_size -= len;
00152 
00153     } while (header_size >= 0);
00154 
00155     switch (rate_flag) {
00156     case -1:
00157         av_log(s, AV_LOG_ERROR, "COMM tag not found!\n");
00158         return -1;
00159     case 44:
00160         st->codec->sample_rate = 44100;
00161         break;
00162     case 22:
00163         st->codec->sample_rate = 22050;
00164         break;
00165     case 11:
00166         st->codec->sample_rate = 11025;
00167         break;
00168     default:
00169         st->codec->sample_rate = rate_flag*1000;
00170         break;
00171     }
00172 
00173     switch (((st->codec->sample_rate/1000) << 8) +
00174             read_bitrate/st->codec->channels) {
00175     case (11<<8) + 8 :
00176     case (8 <<8) + 8 :
00177     case (11<<8) + 10:
00178     case (22<<8) + 32:
00179         size = 512;
00180         break;
00181     case (16<<8) + 16:
00182     case (22<<8) + 20:
00183     case (22<<8) + 24:
00184         size = 1024;
00185         break;
00186     case (44<<8) + 40:
00187     case (44<<8) + 48:
00188         size = 2048;
00189         break;
00190     default:
00191         av_log(s, AV_LOG_ERROR, "Mode not suported: %d Hz, %d kb/s.\n",
00192                st->codec->sample_rate, st->codec->bit_rate);
00193         return -1;
00194     }
00195     c->frame_bit_len = st->codec->bit_rate*size/st->codec->sample_rate;
00196     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00197 
00198     /* put first 12 bytes of COMM chunk in extradata */
00199     if (!(st->codec->extradata = av_malloc(12 + FF_INPUT_BUFFER_PADDING_SIZE)))
00200         return AVERROR(ENOMEM);
00201     st->codec->extradata_size = 12;
00202     memcpy(st->codec->extradata, comm_chunk, 12);
00203 
00204     return 0;
00205 }
00206 
00207 static int vqf_read_packet(AVFormatContext *s, AVPacket *pkt)
00208 {
00209     VqfContext *c = s->priv_data;
00210     int ret;
00211     int size = (c->frame_bit_len - c->remaining_bits + 7)>>3;
00212 
00213     pkt->pos          = avio_tell(s->pb);
00214     pkt->stream_index = 0;
00215 
00216     if (av_new_packet(pkt, size+2) < 0)
00217         return AVERROR(EIO);
00218 
00219     pkt->data[0] = 8 - c->remaining_bits; // Number of bits to skip
00220     pkt->data[1] = c->last_frame_bits;
00221     ret = avio_read(s->pb, pkt->data+2, size);
00222 
00223     if (ret<=0) {
00224         av_free_packet(pkt);
00225         return AVERROR(EIO);
00226     }
00227 
00228     c->last_frame_bits = pkt->data[size+1];
00229     c->remaining_bits  = (size << 3) - c->frame_bit_len + c->remaining_bits;
00230 
00231     return size+2;
00232 }
00233 
00234 static int vqf_read_seek(AVFormatContext *s,
00235                          int stream_index, int64_t timestamp, int flags)
00236 {
00237     VqfContext *c = s->priv_data;
00238     AVStream *st;
00239     int ret;
00240     int64_t pos;
00241 
00242     st = s->streams[stream_index];
00243     pos = av_rescale_rnd(timestamp * st->codec->bit_rate,
00244                          st->time_base.num,
00245                          st->time_base.den * (int64_t)c->frame_bit_len,
00246                          (flags & AVSEEK_FLAG_BACKWARD) ?
00247                                                    AV_ROUND_DOWN : AV_ROUND_UP);
00248     pos *= c->frame_bit_len;
00249 
00250     st->cur_dts = av_rescale(pos, st->time_base.den,
00251                              st->codec->bit_rate * (int64_t)st->time_base.num);
00252 
00253     if ((ret = avio_seek(s->pb, ((pos-7) >> 3) + s->data_offset, SEEK_SET)) < 0)
00254         return ret;
00255 
00256     c->remaining_bits = -7 - ((pos-7)&7);
00257     return 0;
00258 }
00259 
00260 AVInputFormat ff_vqf_demuxer = {
00261     .name           = "vqf",
00262     .long_name      = NULL_IF_CONFIG_SMALL("Nippon Telegraph and Telephone Corporation (NTT) TwinVQ"),
00263     .priv_data_size = sizeof(VqfContext),
00264     .read_probe     = vqf_probe,
00265     .read_header    = vqf_read_header,
00266     .read_packet    = vqf_read_packet,
00267     .read_seek      = vqf_read_seek,
00268     .extensions = "vqf",
00269 };