libavformat/mmf.c

   1 /*
   2  * Yamaha SMAF format
   3  * Copyright (c) 2005 Vidar Madsen
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21 #include "avformat.h"
  22 #include "raw.h"
  23 #include "riff.h"
  24
  25 typedef struct {
  26     offset_t atrpos, atsqpos, awapos;
  27     offset_t data_size;
  28 } MMFContext;
  29
  30 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
  31
  32 static int mmf_rate(int code)
  33 {
  34     if((code < 0) || (code > 4))
  35         return -1;
  36     return mmf_rates[code];
  37 }
  38
  39 #ifdef CONFIG_MMF_MUXER
  40 static int mmf_rate_code(int rate)
  41 {
  42     int i;
  43     for(i = 0; i < 5; i++)
  44         if(mmf_rates[i] == rate)
  45             return i;
  46     return -1;
  47 }
  48
  49 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */
  50 static void end_tag_be(ByteIOContext *pb, offset_t start)
  51 {
  52     offset_t pos;
  53
  54     pos = url_ftell(pb);
  55     url_fseek(pb, start - 4, SEEK_SET);
  56     put_be32(pb, (uint32_t)(pos - start));
  57     url_fseek(pb, pos, SEEK_SET);
  58 }
  59
  60 static int mmf_write_header(AVFormatContext *s)
  61 {
  62     MMFContext *mmf = s->priv_data;
  63     ByteIOContext *pb = s->pb;
  64     offset_t pos;
  65     int rate;
  66
  67     rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
  68     if(rate < 0) {
  69         av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
  70         return -1;
  71     }
  72
  73     put_tag(pb, "MMMD");
  74     put_be32(pb, 0);
  75     pos = start_tag(pb, "CNTI");
  76     put_byte(pb, 0); /* class */
  77     put_byte(pb, 0); /* type */
  78     put_byte(pb, 0); /* code type */
  79     put_byte(pb, 0); /* status */
  80     put_byte(pb, 0); /* counts */
  81     put_tag(pb, "VN:libavcodec,"); /* metadata ("ST:songtitle,VN:version,...") */
  82     end_tag_be(pb, pos);
  83
  84     put_buffer(pb, "ATR\x00", 4);
  85     put_be32(pb, 0);
  86     mmf->atrpos = url_ftell(pb);
  87     put_byte(pb, 0); /* format type */
  88     put_byte(pb, 0); /* sequence type */
  89     put_byte(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
  90     put_byte(pb, 0); /* wave base bit */
  91     put_byte(pb, 2); /* time base d */
  92     put_byte(pb, 2); /* time base g */
  93
  94     put_tag(pb, "Atsq");
  95     put_be32(pb, 16);
  96     mmf->atsqpos = url_ftell(pb);
  97     /* Will be filled on close */
  98     put_buffer(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
  99
 100     mmf->awapos = start_tag(pb, "Awa\x01");
 101
 102     av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
 103
 104     put_flush_packet(pb);
 105
 106     return 0;
 107 }
 108
 109 static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
 110 {
 111     ByteIOContext *pb = s->pb;
 112     put_buffer(pb, pkt->data, pkt->size);
 113     return 0;
 114 }
 115
 116 /* Write a variable-length symbol */
 117 static void put_varlength(ByteIOContext *pb, int val)
 118 {
 119     if(val < 128)
 120         put_byte(pb, val);
 121     else {
 122         val -= 128;
 123         put_byte(pb, 0x80 | val >> 7);
 124         put_byte(pb, 0x7f & val);
 125     }
 126 }
 127
 128 static int mmf_write_trailer(AVFormatContext *s)
 129 {
 130     ByteIOContext *pb = s->pb;
 131     MMFContext *mmf = s->priv_data;
 132     offset_t pos, size;
 133     int gatetime;
 134
 135     if (!url_is_streamed(s->pb)) {
 136         /* Fill in length fields */
 137         end_tag_be(pb, mmf->awapos);
 138         end_tag_be(pb, mmf->atrpos);
 139         end_tag_be(pb, 8);
 140
 141         pos = url_ftell(pb);
 142         size = pos - mmf->awapos;
 143
 144         /* Fill Atsq chunk */
 145         url_fseek(pb, mmf->atsqpos, SEEK_SET);
 146
 147         /* "play wav" */
 148         put_byte(pb, 0); /* start time */
 149         put_byte(pb, 1); /* (channel << 6) | wavenum */
 150         gatetime = size * 500 / s->streams[0]->codec->sample_rate;
 151         put_varlength(pb, gatetime); /* duration */
 152
 153         /* "nop" */
 154         put_varlength(pb, gatetime); /* start time */
 155         put_buffer(pb, "\xff\x00", 2); /* nop */
 156
 157         /* "end of sequence" */
 158         put_buffer(pb, "\x00\x00\x00\x00", 4);
 159
 160         url_fseek(pb, pos, SEEK_SET);
 161
 162         put_flush_packet(pb);
 163     }
 164     return 0;
 165 }
 166 #endif /* CONFIG_MMF_MUXER */
 167
 168 static int mmf_probe(AVProbeData *p)
 169 {
 170     /* check file header */
 171     if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
 172         p->buf[2] == 'M' && p->buf[3] == 'D' &&
 173         p->buf[8] == 'C' && p->buf[9] == 'N' &&
 174         p->buf[10] == 'T' && p->buf[11] == 'I')
 175         return AVPROBE_SCORE_MAX;
 176     else
 177         return 0;
 178 }
 179
 180 /* mmf input */
 181 static int mmf_read_header(AVFormatContext *s,
 182                            AVFormatParameters *ap)
 183 {
 184     MMFContext *mmf = s->priv_data;
 185     unsigned int tag;
 186     ByteIOContext *pb = s->pb;
 187     AVStream *st;
 188     offset_t file_size, size;
 189     int rate, params;
 190
 191     tag = get_le32(pb);
 192     if (tag != MKTAG('M', 'M', 'M', 'D'))
 193         return -1;
 194     file_size = get_be32(pb);
 195
 196     /* Skip some unused chunks that may or may not be present */
 197     for(;; url_fseek(pb, size, SEEK_CUR)) {
 198         tag = get_le32(pb);
 199         size = get_be32(pb);
 200         if(tag == MKTAG('C','N','T','I')) continue;
 201         if(tag == MKTAG('O','P','D','A')) continue;
 202         break;
 203     }
 204
 205     /* Tag = "ATRx", where "x" = track number */
 206     if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
 207         av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
 208         return -1;
 209     }
 210     if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
 211         av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
 212         return -1;
 213     }
 214
 215     get_byte(pb); /* format type */
 216     get_byte(pb); /* sequence type */
 217     params = get_byte(pb); /* (channel << 7) | (format << 4) | rate */
 218     rate = mmf_rate(params & 0x0f);
 219     if(rate  < 0) {
 220         av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
 221         return -1;
 222     }
 223     get_byte(pb); /* wave base bit */
 224     get_byte(pb); /* time base d */
 225     get_byte(pb); /* time base g */
 226
 227     /* Skip some unused chunks that may or may not be present */
 228     for(;; url_fseek(pb, size, SEEK_CUR)) {
 229         tag = get_le32(pb);
 230         size = get_be32(pb);
 231         if(tag == MKTAG('A','t','s','q')) continue;
 232         if(tag == MKTAG('A','s','p','I')) continue;
 233         break;
 234     }
 235
 236     /* Make sure it's followed by an Awa chunk, aka wave data */
 237     if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
 238         av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
 239         return -1;
 240     }
 241     mmf->data_size = size;
 242
 243     st = av_new_stream(s, 0);
 244     if (!st)
 245         return AVERROR(ENOMEM);
 246
 247     st->codec->codec_type = CODEC_TYPE_AUDIO;
 248     st->codec->codec_id = CODEC_ID_ADPCM_YAMAHA;
 249     st->codec->sample_rate = rate;
 250     st->codec->channels = 1;
 251     st->codec->bits_per_sample = 4;
 252     st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_sample;
 253
 254     av_set_pts_info(st, 64, 1, st->codec->sample_rate);
 255
 256     return 0;
 257 }
 258
 259 #define MAX_SIZE 4096
 260
 261 static int mmf_read_packet(AVFormatContext *s,
 262                            AVPacket *pkt)
 263 {
 264     MMFContext *mmf = s->priv_data;
 265     AVStream *st;
 266     int ret, size;
 267
 268     if (url_feof(s->pb))
 269         return AVERROR(EIO);
 270     st = s->streams[0];
 271
 272     size = MAX_SIZE;
 273     if(size > mmf->data_size)
 274         size = mmf->data_size;
 275
 276     if(!size)
 277         return AVERROR(EIO);
 278
 279     if (av_new_packet(pkt, size))
 280         return AVERROR(EIO);
 281     pkt->stream_index = 0;
 282
 283     ret = get_buffer(s->pb, pkt->data, pkt->size);
 284     if (ret < 0)
 285         av_free_packet(pkt);
 286
 287     mmf->data_size -= ret;
 288
 289     pkt->size = ret;
 290     return ret;
 291 }
 292
 293 #ifdef CONFIG_MMF_DEMUXER
 294 AVInputFormat mmf_demuxer = {
 295     "mmf",
 296     NULL_IF_CONFIG_SMALL("mmf format"),
 297     sizeof(MMFContext),
 298     mmf_probe,
 299     mmf_read_header,
 300     mmf_read_packet,
 301     NULL,
 302     pcm_read_seek,
 303 };
 304 #endif
 305 #ifdef CONFIG_MMF_MUXER
 306 AVOutputFormat mmf_muxer = {
 307     "mmf",
 308     NULL_IF_CONFIG_SMALL("mmf format"),
 309     "application/vnd.smaf",
 310     "mmf",
 311     sizeof(MMFContext),
 312     CODEC_ID_ADPCM_YAMAHA,
 313     CODEC_ID_NONE,
 314     mmf_write_header,
 315     mmf_write_packet,
 316     mmf_write_trailer,
 317 };
 318 #endif