libavformat/mmf.c

   1 /*
   2  * Yamaha SMAF format
   3  * Copyright (c) 2005 Vidar Madsen
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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 "avformat.h"
  24 #include "internal.h"
  25 #include "avio_internal.h"
  26 #include "pcm.h"
  27 #include "riff.h"
  28
  29 typedef struct {
  30     int64_t atrpos, atsqpos, awapos;
  31     int64_t data_size;
  32 } MMFContext;
  33
  34 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
  35
  36 static int mmf_rate(int code)
  37 {
  38     if((code < 0) || (code > 4))
  39         return -1;
  40     return mmf_rates[code];
  41 }
  42
  43 #if CONFIG_MMF_MUXER
  44 static int mmf_rate_code(int rate)
  45 {
  46     int i;
  47     for(i = 0; i < 5; i++)
  48         if(mmf_rates[i] == rate)
  49             return i;
  50     return -1;
  51 }
  52
  53 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */
  54 static void end_tag_be(AVIOContext *pb, int64_t start)
  55 {
  56     int64_t pos;
  57
  58     pos = avio_tell(pb);
  59     avio_seek(pb, start - 4, SEEK_SET);
  60     avio_wb32(pb, (uint32_t)(pos - start));
  61     avio_seek(pb, pos, SEEK_SET);
  62 }
  63
  64 static int mmf_write_header(AVFormatContext *s)
  65 {
  66     MMFContext *mmf = s->priv_data;
  67     AVIOContext *pb = s->pb;
  68     int64_t pos;
  69     int rate;
  70
  71     rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
  72     if(rate < 0) {
  73         av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
  74         return -1;
  75     }
  76
  77     ffio_wfourcc(pb, "MMMD");
  78     avio_wb32(pb, 0);
  79     pos = ff_start_tag(pb, "CNTI");
  80     avio_w8(pb, 0); /* class */
  81     avio_w8(pb, 0); /* type */
  82     avio_w8(pb, 0); /* code type */
  83     avio_w8(pb, 0); /* status */
  84     avio_w8(pb, 0); /* counts */
  85     avio_write(pb, "VN:libavcodec,", sizeof("VN:libavcodec,") -1); /* metadata ("ST:songtitle,VN:version,...") */
  86     end_tag_be(pb, pos);
  87
  88     avio_write(pb, "ATR\x00", 4);
  89     avio_wb32(pb, 0);
  90     mmf->atrpos = avio_tell(pb);
  91     avio_w8(pb, 0); /* format type */
  92     avio_w8(pb, 0); /* sequence type */
  93     avio_w8(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
  94     avio_w8(pb, 0); /* wave base bit */
  95     avio_w8(pb, 2); /* time base d */
  96     avio_w8(pb, 2); /* time base g */
  97
  98     ffio_wfourcc(pb, "Atsq");
  99     avio_wb32(pb, 16);
 100     mmf->atsqpos = avio_tell(pb);
 101     /* Will be filled on close */
 102     avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
 103
 104     mmf->awapos = ff_start_tag(pb, "Awa\x01");
 105
 106     avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
 107
 108     avio_flush(pb);
 109
 110     return 0;
 111 }
 112
 113 static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
 114 {
 115     AVIOContext *pb = s->pb;
 116     avio_write(pb, pkt->data, pkt->size);
 117     return 0;
 118 }
 119
 120 /* Write a variable-length symbol */
 121 static void put_varlength(AVIOContext *pb, int val)
 122 {
 123     if(val < 128)
 124         avio_w8(pb, val);
 125     else {
 126         val -= 128;
 127         avio_w8(pb, 0x80 | val >> 7);
 128         avio_w8(pb, 0x7f & val);
 129     }
 130 }
 131
 132 static int mmf_write_trailer(AVFormatContext *s)
 133 {
 134     AVIOContext *pb = s->pb;
 135     MMFContext *mmf = s->priv_data;
 136     int64_t pos, size;
 137     int gatetime;
 138
 139     if (s->pb->seekable) {
 140         /* Fill in length fields */
 141         end_tag_be(pb, mmf->awapos);
 142         end_tag_be(pb, mmf->atrpos);
 143         end_tag_be(pb, 8);
 144
 145         pos = avio_tell(pb);
 146         size = pos - mmf->awapos;
 147
 148         /* Fill Atsq chunk */
 149         avio_seek(pb, mmf->atsqpos, SEEK_SET);
 150
 151         /* "play wav" */
 152         avio_w8(pb, 0); /* start time */
 153         avio_w8(pb, 1); /* (channel << 6) | wavenum */
 154         gatetime = size * 500 / s->streams[0]->codec->sample_rate;
 155         put_varlength(pb, gatetime); /* duration */
 156
 157         /* "nop" */
 158         put_varlength(pb, gatetime); /* start time */
 159         avio_write(pb, "\xff\x00", 2); /* nop */
 160
 161         /* "end of sequence" */
 162         avio_write(pb, "\x00\x00\x00\x00", 4);
 163
 164         avio_seek(pb, pos, SEEK_SET);
 165
 166         avio_flush(pb);
 167     }
 168     return 0;
 169 }
 170 #endif /* CONFIG_MMF_MUXER */
 171
 172 static int mmf_probe(AVProbeData *p)
 173 {
 174     /* check file header */
 175     if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
 176         p->buf[2] == 'M' && p->buf[3] == 'D' &&
 177         p->buf[8] == 'C' && p->buf[9] == 'N' &&
 178         p->buf[10] == 'T' && p->buf[11] == 'I')
 179         return AVPROBE_SCORE_MAX;
 180     else
 181         return 0;
 182 }
 183
 184 /* mmf input */
 185 static int mmf_read_header(AVFormatContext *s)
 186 {
 187     MMFContext *mmf = s->priv_data;
 188     unsigned int tag;
 189     AVIOContext *pb = s->pb;
 190     AVStream *st;
 191     int64_t size;
 192     int rate, params;
 193
 194     tag = avio_rl32(pb);
 195     if (tag != MKTAG('M', 'M', 'M', 'D'))
 196         return -1;
 197     avio_skip(pb, 4); /* file_size */
 198
 199     /* Skip some unused chunks that may or may not be present */
 200     for(;; avio_skip(pb, size)) {
 201         tag = avio_rl32(pb);
 202         size = avio_rb32(pb);
 203         if(tag == MKTAG('C','N','T','I')) continue;
 204         if(tag == MKTAG('O','P','D','A')) continue;
 205         break;
 206     }
 207
 208     /* Tag = "ATRx", where "x" = track number */
 209     if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
 210         av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
 211         return -1;
 212     }
 213     if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
 214         av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
 215         return -1;
 216     }
 217
 218     avio_r8(pb); /* format type */
 219     avio_r8(pb); /* sequence type */
 220     params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
 221     rate = mmf_rate(params & 0x0f);
 222     if(rate  < 0) {
 223         av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
 224         return -1;
 225     }
 226     avio_r8(pb); /* wave base bit */
 227     avio_r8(pb); /* time base d */
 228     avio_r8(pb); /* time base g */
 229
 230     /* Skip some unused chunks that may or may not be present */
 231     for(;; avio_skip(pb, size)) {
 232         tag = avio_rl32(pb);
 233         size = avio_rb32(pb);
 234         if(tag == MKTAG('A','t','s','q')) continue;
 235         if(tag == MKTAG('A','s','p','I')) continue;
 236         break;
 237     }
 238
 239     /* Make sure it's followed by an Awa chunk, aka wave data */
 240     if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
 241         av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
 242         return -1;
 243     }
 244     mmf->data_size = size;
 245
 246     st = avformat_new_stream(s, NULL);
 247     if (!st)
 248         return AVERROR(ENOMEM);
 249
 250     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 251     st->codec->codec_id = AV_CODEC_ID_ADPCM_YAMAHA;
 252     st->codec->sample_rate = rate;
 253     st->codec->channels = 1;
 254     st->codec->channel_layout = AV_CH_LAYOUT_MONO;
 255     st->codec->bits_per_coded_sample = 4;
 256     st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample;
 257
 258     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
 259
 260     return 0;
 261 }
 262
 263 #define MAX_SIZE 4096
 264
 265 static int mmf_read_packet(AVFormatContext *s,
 266                            AVPacket *pkt)
 267 {
 268     MMFContext *mmf = s->priv_data;
 269     int ret, size;
 270
 271     if (s->pb->eof_reached)
 272         return AVERROR(EIO);
 273
 274     size = MAX_SIZE;
 275     if(size > mmf->data_size)
 276         size = mmf->data_size;
 277
 278     if(!size)
 279         return AVERROR(EIO);
 280
 281     if (av_new_packet(pkt, size))
 282         return AVERROR(EIO);
 283     pkt->stream_index = 0;
 284
 285     ret = avio_read(s->pb, pkt->data, pkt->size);
 286     if (ret < 0)
 287         av_free_packet(pkt);
 288
 289     mmf->data_size -= ret;
 290
 291     pkt->size = ret;
 292     return ret;
 293 }
 294
 295 #if CONFIG_MMF_DEMUXER
 296 AVInputFormat ff_mmf_demuxer = {
 297     .name           = "mmf",
 298     .long_name      = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
 299     .priv_data_size = sizeof(MMFContext),
 300     .read_probe     = mmf_probe,
 301     .read_header    = mmf_read_header,
 302     .read_packet    = mmf_read_packet,
 303     .read_seek      = ff_pcm_read_seek,
 304 };
 305 #endif
 306 #if CONFIG_MMF_MUXER
 307 AVOutputFormat ff_mmf_muxer = {
 308     .name              = "mmf",
 309     .long_name         = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
 310     .mime_type         = "application/vnd.smaf",
 311     .extensions        = "mmf",
 312     .priv_data_size    = sizeof(MMFContext),
 313     .audio_codec       = AV_CODEC_ID_ADPCM_YAMAHA,
 314     .video_codec       = AV_CODEC_ID_NONE,
 315     .write_header      = mmf_write_header,
 316     .write_packet      = mmf_write_packet,
 317     .write_trailer     = mmf_write_trailer,
 318 };
 319 #endif