1 /*****************************************************************************
2 * smf.c : Standard MIDI File (.mid) demux module for vlc
3 *****************************************************************************
4 * Copyright © 2007 Rémi Denis-Courmont
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program 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
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
20 *****************************************************************************/
26 #include <vlc_common.h>
27 #include <vlc_plugin.h>
28 #include <vlc_demux.h>
30 #include <vlc_charset.h>
36 #define TEMPO_MAX 250 /* Beats per minute */
38 static int Open (vlc_object_t *);
39 static void Close (vlc_object_t *);
42 set_description (N_("SMF demuxer"))
43 set_category (CAT_INPUT)
44 set_subcategory (SUBCAT_INPUT_DEMUX)
45 set_capability ("demux", 20)
46 set_callbacks (Open, Close)
49 static int Demux (demux_t *);
50 static int Control (demux_t *, int i_query, va_list args);
52 typedef struct smf_track_t
54 int64_t offset; /* Read offset in the file (stream_Tell) */
55 int64_t end; /* End offset in the file */
56 uint64_t next; /* Time of next message (in term of pulses) */
57 uint8_t running_event; /* Running (previous) event */
60 static int ReadDeltaTime (stream_t *s, mtrk_t *track);
66 uint64_t pulse; /* Pulses counter */
68 unsigned ppqn; /* Pulses Per Quarter Note */
69 /* by the way, "quarter note" is "noire" in French */
71 unsigned trackc; /* Number of tracks */
72 mtrk_t trackv[0]; /* Track states */
75 /*****************************************************************************
76 * Open: check file and initializes structures
77 *****************************************************************************/
78 static int Open (vlc_object_t * p_this)
80 demux_t *p_demux = (demux_t *)p_this;
81 stream_t *stream = p_demux->s;
84 unsigned tracks, ppqn;
87 /* (Try to) parse the SMF header */
88 /* Header chunk always has 6 bytes payload */
89 if (stream_Peek (stream, &peek, 14) < 14)
92 /* Skip RIFF MIDI header if present */
93 if (!memcmp (peek, "RIFF", 4) && !memcmp (peek + 8, "RMID", 4))
95 uint32_t riff_len = GetDWLE (peek + 4);
97 msg_Dbg (p_this, "detected RIFF MIDI file (%u bytes)",
99 if ((stream_Read (stream, NULL, 12) < 12))
102 /* Look for the RIFF data chunk */
109 || (stream_Read (stream, chnk_hdr, 8) < 8))
113 chnk_len = GetDWLE (chnk_hdr + 4);
114 if (riff_len < chnk_len)
116 riff_len -= chnk_len;
118 if (!memcmp (chnk_hdr, "data", 4))
121 if (stream_Read (stream, NULL, chnk_len) < (ssize_t)chnk_len)
125 /* Read real SMF header. Assume RIFF data chunk length is proper. */
126 if (stream_Peek (stream, &peek, 14) < 14)
130 if (memcmp (peek, "MThd\x00\x00\x00\x06", 8))
134 /* First word: SMF type */
135 switch (GetWBE (peek))
144 /* We don't implement SMF2 (as do many) */
145 msg_Err (p_this, "unsupported SMF file type %u", GetWBE (peek));
150 /* Second word: number of tracks */
151 tracks = GetWBE (peek);
153 if (!multitrack && (tracks != 1))
155 msg_Err (p_this, "invalid SMF type 0 file");
159 msg_Dbg (p_this, "detected Standard MIDI File (type %u) with %u track(s)",
162 /* Third/last word: timing */
163 ppqn = GetWBE (peek);
167 msg_Err (p_this, "SMPTE timestamps not implemented");
172 msg_Dbg (p_this, " %u pulses per quarter note", ppqn);
175 p_sys = malloc (sizeof (*p_sys) + (sizeof (mtrk_t) * tracks));
179 /* We've had a valid SMF header - now skip it*/
180 if (stream_Read (stream, NULL, 14) < 14)
183 p_demux->pf_demux = Demux;
184 p_demux->pf_control = Control;
185 p_demux->p_sys = p_sys;
187 /* Default SMF tempo is 120BPM, i.e. half a second per quarter note */
188 date_Init (&p_sys->pts, ppqn * 2, 1);
189 date_Set (&p_sys->pts, 0);
193 p_sys->trackc = tracks;
194 /* Prefetch track offsets */
195 for (unsigned i = 0; i < tracks; i++)
201 /* Seeking screws streaming up, but there is no way around this,
202 * as SMF1 tracks are performed simultaneously.
203 * Not a big deal as SMF1 are usually only a few kbytes anyway. */
204 if (stream_Seek (stream, p_sys->trackv[i-1].end))
206 msg_Err (p_this, "cannot build SMF index (corrupted file?)");
213 stream_Read (stream, head, 8);
214 if (memcmp (head, "MTrk", 4) == 0)
217 msg_Dbg (p_this, "skipping unknown SMF chunk");
218 stream_Read (stream, NULL, GetDWBE (head + 4));
221 p_sys->trackv[i].offset = stream_Tell (stream);
222 p_sys->trackv[i].end = p_sys->trackv[i].offset + GetDWBE (head + 4);
223 p_sys->trackv[i].next = 0;
224 ReadDeltaTime (stream, p_sys->trackv + i);
225 p_sys->trackv[i].running_event = 0xF6;
226 /* Why 0xF6 (Tuning Calibration)?
227 * Because it has zero bytes of data, so the parser will detect the
228 * error if the first event uses running status. */
232 es_format_Init (&fmt, AUDIO_ES, VLC_CODEC_MIDI);
233 fmt.audio.i_channels = 2;
234 fmt.audio.i_original_channels = fmt.audio.i_physical_channels =
235 AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
236 fmt.audio.i_rate = 44100; /* dummy value */
237 p_sys->es = es_out_Add (p_demux->out, &fmt);
247 * Releases allocate resources.
249 static void Close (vlc_object_t * p_this)
251 demux_t *p_demux = (demux_t *)p_this;
252 demux_sys_t *p_sys = p_demux->p_sys;
258 * Reads MIDI variable length (7, 14, 21 or 28 bits) integer.
259 * @return read value, or -1 on EOF/error.
261 static int32_t ReadVarInt (stream_t *s)
266 for (unsigned i = 0; i < 4; i++)
268 if (stream_Read (s, &byte, 1) < 1)
271 val = (val << 7) | (byte & 0x7f);
272 if ((byte & 0x80) == 0)
281 * Reads (delta) time from the next event of a given track.
282 * @param s stream to read data from (must be positioned at the right offset)
284 static int ReadDeltaTime (stream_t *s, mtrk_t *track)
288 assert (stream_Tell (s) == track->offset);
290 if (track->offset >= track->end)
292 /* This track is done */
293 track->next = UINT64_MAX;
297 delta_time = ReadVarInt (s);
301 track->next += delta_time;
302 track->offset = stream_Tell (s);
308 * Non-MIDI Meta events handler
311 int HandleMeta (demux_t *p_demux, mtrk_t *tr)
313 stream_t *s = p_demux->s;
314 demux_sys_t *p_sys = p_demux->p_sys;
320 if (stream_Read (s, &type, 1) != 1)
323 length = ReadVarInt (s);
327 payload = malloc (length + 1);
328 if ((payload == NULL)
329 || (stream_Read (s, payload, length) != length))
335 payload[length] = '\0';
339 case 0x00: /* Sequence Number */
342 case 0x01: /* Text (comment) */
343 EnsureUTF8 ((char *)payload);
344 msg_Info (p_demux, "Text : %s", (char *)payload);
347 case 0x02: /* Copyright */
348 EnsureUTF8 ((char *)payload);
349 msg_Info (p_demux, "Copyright : %s", (char *)payload);
352 case 0x03: /* Track name */
353 EnsureUTF8 ((char *)payload);
354 msg_Info (p_demux, "Track name: %s", (char *)payload);
357 case 0x04: /* Instrument name */
358 EnsureUTF8 ((char *)payload);
359 msg_Info (p_demux, "Instrument: %s", (char *)payload);
362 case 0x05: /* Lyric (one syllable) */
363 /*EnsureUTF8 ((char *)payload);*/
366 case 0x06: /* Marker text */
367 EnsureUTF8 ((char *)payload);
368 msg_Info (p_demux, "Marker : %s", (char *)payload);
370 case 0x07: /* Cue point (WAVE filename) */
371 EnsureUTF8 ((char *)payload);
372 msg_Info (p_demux, "Cue point : %s", (char *)payload);
375 case 0x08: /* Program/Patch name */
376 EnsureUTF8 ((char *)payload);
377 msg_Info (p_demux, "Patch name: %s", (char *)payload);
380 case 0x09: /* MIDI port name */
381 EnsureUTF8 ((char *)payload);
382 msg_Dbg (p_demux, "MIDI port : %s", (char *)payload);
385 case 0x2F: /* End of track */
386 if (tr->end != stream_Tell (s))
388 msg_Err (p_demux, "misplaced end of track");
393 case 0x51: /* Tempo */
396 uint32_t uspqn = (payload[0] << 16)
397 | (payload[1] << 8) | payload[2];
398 unsigned tempo = 60 * 1000000 / (uspqn ? uspqn : 1);
399 msg_Dbg (p_demux, "tempo: %uus/qn -> %u BPM",
400 (unsigned)uspqn, tempo);
402 if (tempo < TEMPO_MIN)
404 msg_Warn (p_demux, "tempo too slow -> %u BPM", TEMPO_MIN);
408 if (tempo > TEMPO_MAX)
410 msg_Warn (p_demux, "tempo too fast -> %u BPM", TEMPO_MAX);
413 date_Change (&p_sys->pts, p_sys->ppqn * tempo, 60);
419 case 0x54: /* SMPTE offset */
421 msg_Warn (p_demux, "SMPTE offset not implemented");
426 case 0x58: /* Time signature */
433 case 0x59: /* Key signature */
440 case 0x7f: /* Proprietary event */
441 msg_Dbg (p_demux, "ignored proprietary SMF Meta Event (%d bytes)",
446 msg_Warn (p_demux, "unknown SMF Meta Event type 0x%02X (%d bytes)",
457 int HandleMessage (demux_t *p_demux, mtrk_t *tr)
459 stream_t *s = p_demux->s;
461 uint8_t first, event;
464 if (stream_Seek (s, tr->offset)
465 || (stream_Read (s, &first, 1) != 1))
468 event = (first & 0x80) ? first : tr->running_event;
470 switch (event & 0xf0)
472 case 0xF0: /* System Exclusive */
475 case 0xF0: /* System Specific start */
476 case 0xF7: /* System Specific continuation */
478 /* Variable length followed by SysEx event data */
479 int32_t len = ReadVarInt (s);
483 block = stream_Block (s, len);
486 block = block_Realloc (block, 1, len);
489 block->p_buffer[0] = event;
492 case 0xFF: /* SMF Meta Event */
493 if (HandleMeta (p_demux, tr))
495 /* We MUST NOT pass this event forward. It would be
496 * confused as a MIDI Reset real-time event. */
507 /* We cannot handle undefined "common" (non-real-time)
508 * events inside SMF, as we cannot differentiate a
509 * one byte delta-time (< 0x80) from event data. */
524 /* FIXME: one message per block is very inefficient */
525 block = block_New (p_demux, 1 + datalen);
529 block->p_buffer[0] = event;
532 stream_Read (s, block->p_buffer + 1, datalen);
538 msg_Err (p_demux, "malformatted MIDI event");
539 return -1; /* can't use implicit running status with empty payload! */
542 block->p_buffer[1] = first;
544 stream_Read (s, block->p_buffer + 2, datalen - 1);
548 block->i_dts = block->i_pts = VLC_TS_0 + date_Get (&p_demux->p_sys->pts);
549 es_out_Send (p_demux->out, p_demux->p_sys->es, block);
553 /* If event is not real-time, update running status */
554 tr->running_event = event;
556 tr->offset = stream_Tell (s);
560 /*****************************************************************************
561 * Demux: read chunks and send them to the synthetizer
562 *****************************************************************************
563 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
564 *****************************************************************************/
565 static int Demux (demux_t *p_demux)
567 stream_t *s = p_demux->s;
568 demux_sys_t *p_sys = p_demux->p_sys;
569 uint64_t pulse = p_sys->pulse, next_pulse = UINT64_MAX;
571 if (pulse == UINT64_MAX)
572 return 0; /* all tracks are done */
574 es_out_Control (p_demux->out, ES_OUT_SET_PCR, VLC_TS_0 + date_Get (&p_sys->pts));
576 for (unsigned i = 0; i < p_sys->trackc; i++)
578 mtrk_t *track = p_sys->trackv + i;
580 while (track->next == pulse)
582 if (HandleMessage (p_demux, track)
583 || ReadDeltaTime (s, track))
585 msg_Err (p_demux, "fatal parsing error");
590 if (track->next < next_pulse)
591 next_pulse = track->next;
594 mtime_t cur_tick = (date_Get (&p_sys->pts) + 9999) / 10000, last_tick;
595 if (next_pulse != UINT64_MAX)
596 last_tick = date_Increment (&p_sys->pts, next_pulse - pulse) / 10000;
598 last_tick = cur_tick + 1;
600 /* MIDI Tick emulation (ping the decoder every 10ms) */
601 while (cur_tick < last_tick)
603 block_t *tick = block_New (p_demux, 1);
607 tick->p_buffer[0] = 0xF9;
608 tick->i_dts = tick->i_pts = VLC_TS_0 + cur_tick++ * 10000;
609 es_out_Send (p_demux->out, p_sys->es, tick);
612 p_sys->pulse = next_pulse;
618 /*****************************************************************************
620 *****************************************************************************/
621 static int Control (demux_t *p_demux, int i_query, va_list args)
623 demux_sys_t *p_sys = p_demux->p_sys;
629 *(va_arg (args, int64_t *)) = date_Get (&p_sys->pts);
635 case DEMUX_GET_POSITION:
636 case DEMUX_SET_POSITION:
637 case DEMUX_GET_LENGTH: