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 *****************************************************************************/
23 #include <vlc_demux.h>
25 #include <vlc_codecs.h>
26 #include <vlc_charset.h>
30 #define TEMPO_MAX 250 /* Beats per minute */
32 static int Open (vlc_object_t *);
33 static void Close (vlc_object_t *);
36 set_description (_("SMF demuxer"));
37 set_category (CAT_INPUT);
38 set_subcategory (SUBCAT_INPUT_DEMUX);
39 set_capability ("demux2", 20);
40 set_callbacks (Open, Close);
43 static int Demux (demux_t *);
44 static int Control (demux_t *, int i_query, va_list args);
46 typedef struct smf_track_t
48 int64_t offset; /* Read offset in the file (stream_Tell) */
49 int64_t end; /* End offset in the file */
50 uint64_t next; /* Time of next message (in term of pulses) */
51 uint8_t running_event; /* Running (previous) event */
54 static int ReadDeltaTime (stream_t *s, mtrk_t *track);
60 uint64_t pulse; /* Pulses counter */
62 unsigned ppqn; /* Pulses Per Quarter Note */
63 /* by the way, "quarter note" is "noire" in French */
65 unsigned trackc; /* Number of tracks */
66 mtrk_t trackv[0]; /* Track states */
69 /*****************************************************************************
70 * Open: check file and initializes structures
71 *****************************************************************************/
72 static int Open (vlc_object_t * p_this)
74 demux_t *p_demux = (demux_t *)p_this;
75 stream_t *stream = p_demux->s;
78 unsigned tracks, ppqn;
79 vlc_bool_t multitrack;
81 /* (Try to) parse the SMF header */
82 /* Header chunk always has 6 bytes payload */
83 if (stream_Peek (stream, &peek, 14) < 14)
86 if (memcmp (peek, "MThd\x00\x00\x00\x06", 8))
90 /* First word: SMF type */
91 switch (GetWBE (peek))
94 multitrack = VLC_FALSE;
97 multitrack = VLC_TRUE;
100 /* We don't implement SMF2 (as do many) */
101 msg_Err (p_this, "unsupported SMF file type %u", GetWBE (peek));
106 /* Second word: number of tracks */
107 tracks = GetWBE (peek);
109 if (!multitrack && (tracks != 1))
111 msg_Err (p_this, "invalid SMF type 0 file");
115 msg_Dbg (p_this, "detected Standard MIDI File (type %u) with %u track(s)",
118 /* Third/last word: timing */
119 ppqn = GetWBE (peek);
123 msg_Err (p_this, "SMPTE timestamps not implemented");
128 msg_Dbg (p_this, " %u pulses per quarter note", ppqn);
131 p_sys = malloc (sizeof (*p_sys) + (sizeof (mtrk_t) * tracks));
135 /* We've had a valid SMF header - now skip it*/
136 if (stream_Read (stream, NULL, 14) < 14)
139 p_demux->pf_demux = Demux;
140 p_demux->pf_control = Control;
141 p_demux->p_sys = p_sys;
143 /* Default SMF tempo is 120BPM, i.e. half a second per quarter note */
144 date_Init (&p_sys->pts, ppqn * 2, 1);
145 date_Set (&p_sys->pts, 1);
149 p_sys->trackc = tracks;
150 /* Prefetch track offsets */
151 for (unsigned i = 0; i < tracks; i++)
157 /* Seeking screws streaming up, but there is no way around this,
158 * as SMF1 tracks are performed simultaneously.
159 * Not a big deal as SMF1 are usually only a few kbytes anyway. */
160 if (stream_Seek (stream, p_sys->trackv[i-1].end))
162 msg_Err (p_this, "cannot build SMF index (corrupted file?)");
169 stream_Read (stream, head, 8);
170 if (memcmp (head, "MTrk", 4) == 0)
173 msg_Dbg (p_this, "skipping unknown SMF chunk");
174 stream_Read (stream, NULL, GetDWBE (head + 4));
177 p_sys->trackv[i].offset = stream_Tell (stream);
178 p_sys->trackv[i].end = p_sys->trackv[i].offset + GetDWBE (head + 4);
179 p_sys->trackv[i].next = 0;
180 ReadDeltaTime (stream, p_sys->trackv + i);
181 p_sys->trackv[i].running_event = 0xF6;
182 /* Why 0xF6 (Tuning Calibration)?
183 * Because it has zero bytes of data, so the parser will detect the
184 * error if the first event uses running status. */
188 es_format_Init (&fmt, AUDIO_ES, VLC_FOURCC('M', 'I', 'D', 'I'));
189 p_sys->es = es_out_Add (p_demux->out, &fmt);
199 * Releases allocate resources.
201 static void Close (vlc_object_t * p_this)
203 demux_t *p_demux = (demux_t *)p_this;
204 demux_sys_t *p_sys = p_demux->p_sys;
210 * Reads MIDI variable length (7, 14, 21 or 28 bits) integer.
211 * @return read value, or -1 on EOF/error.
213 static int32_t ReadVarInt (stream_t *s)
218 for (unsigned i = 0; i < 4; i++)
220 if (stream_Read (s, &byte, 1) < 1)
223 val = (val << 7) | (byte & 0x7f);
224 if ((byte & 0x80) == 0)
233 * Reads (delta) time from the next event of a given track.
234 * @param s stream to read data from (must be positioned at the right offset)
236 static int ReadDeltaTime (stream_t *s, mtrk_t *track)
240 assert (stream_Tell (s) == track->offset);
242 if (track->offset >= track->end)
244 /* This track is done */
245 track->next = UINT64_MAX;
249 delta_time = ReadVarInt (s);
253 track->next += delta_time;
254 track->offset = stream_Tell (s);
260 * Non-MIDI Meta events handler
263 int HandleMeta (demux_t *p_demux, mtrk_t *tr)
265 stream_t *s = p_demux->s;
266 demux_sys_t *p_sys = p_demux->p_sys;
272 if (stream_Read (s, &type, 1) != 1)
275 length = ReadVarInt (s);
279 payload = malloc (length + 1);
280 if ((payload == NULL)
281 || (stream_Read (s, payload, length) != length))
287 payload[length] = '\0';
291 case 0x00: /* Sequence Number */
294 case 0x01: /* Test (comment) */
295 EnsureUTF8 ((char *)payload);
296 msg_Info (p_demux, "Text : %s", (char *)payload);
299 case 0x02: /* Copyright */
300 EnsureUTF8 ((char *)payload);
301 msg_Info (p_demux, "Copyright : %s", (char *)payload);
304 case 0x03: /* Track name */
305 EnsureUTF8 ((char *)payload);
306 msg_Info (p_demux, "Track name: %s", (char *)payload);
309 case 0x04: /* Instrument name */
310 EnsureUTF8 ((char *)payload);
311 msg_Info (p_demux, "Instrument: %s", (char *)payload);
314 case 0x05: /* Lyric (one syllable) */
315 /*EnsureUTF8 ((char *)payload);*/
318 case 0x06: /* Marker text */
319 EnsureUTF8 ((char *)payload);
320 msg_Info (p_demux, "Marker : %s", (char *)payload);
322 case 0x07: /* Cue point (WAVE filename) */
323 EnsureUTF8 ((char *)payload);
324 msg_Info (p_demux, "Cue point : %s", (char *)payload);
327 case 0x08: /* Program/Patch name */
328 EnsureUTF8 ((char *)payload);
329 msg_Info (p_demux, "Patch name: %s", (char *)payload);
332 case 0x09: /* MIDI port name */
333 EnsureUTF8 ((char *)payload);
334 msg_Dbg (p_demux, "MIDI port : %s", (char *)payload);
337 case 0x2F: /* End of track */
338 if (tr->end != stream_Tell (s))
340 msg_Err (p_demux, "misplaced end of track");
345 case 0x51: /* Tempo */
348 uint32_t uspqn = (payload[0] << 16)
349 | (payload[1] << 8) | payload[2];
350 unsigned tempo = 60 * 1000000 / (uspqn ? uspqn : 1);
351 msg_Dbg (p_demux, "tempo: %uus/qn -> %u BPM",
352 (unsigned)uspqn, tempo);
354 if (tempo < TEMPO_MIN)
356 msg_Warn (p_demux, "tempo too slow -> %u BPM", TEMPO_MIN);
360 if (tempo > TEMPO_MAX)
362 msg_Warn (p_demux, "tempo too fast -> %u BPM", TEMPO_MAX);
365 date_Change (&p_sys->pts, p_sys->ppqn * tempo, 60);
371 case 0x54: /* SMPTE offset */
373 msg_Warn (p_demux, "SMPTE offset not implemented");
378 case 0x58: /* Time signature */
385 case 0x59: /* Key signature */
392 case 0x7f: /* Proprietary event */
393 msg_Dbg (p_demux, "ignored proprietary SMF Meta Event (%d bytes)",
398 msg_Warn (p_demux, "unknown SMF Meta Event type 0x%02X (%d bytes)",
409 int HandleMessage (demux_t *p_demux, mtrk_t *tr)
411 stream_t *s = p_demux->s;
413 uint8_t first, event;
416 if (stream_Seek (s, tr->offset)
417 || (stream_Read (s, &first, 1) != 1))
420 event = (first & 0x80) ? first : tr->running_event;
422 switch (event & 0xf0)
424 case 0xF0: /* System Exclusive */
427 case 0xF0: /* System Specific */
429 /* TODO: don't skip these */
430 stream_Read (s, NULL, 1); /* Manuf ID */
434 if (stream_Read (s, &c, 1) != 1)
440 case 0xFF: /* SMF Meta Event */
441 if (HandleMeta (p_demux, tr))
443 /* We MUST NOT pass this event to forward. It would be
444 * confused as a MIDI Reset real-time event. */
455 /* We cannot handle undefined "common" (non-real-time)
456 * events inside SMF, as we cannot differentiate a
457 * one byte delta-time (< 0x80) from event data. */
458 case 0xF7: /* End of sysex -> should never happen(?) */
459 msg_Err (p_demux, "unknown MIDI event 0x%02X", event);
460 return -1; /* undefined events */
474 /* FIXME: one message per block is very inefficient */
475 block = block_New (p_demux, 1 + datalen);
479 block->p_buffer[0] = event;
482 stream_Read (s, block->p_buffer + 1, datalen);
488 msg_Err (p_demux, "malformatted MIDI event");
489 return -1; /* can't use implicit running status with empty payload! */
492 block->p_buffer[1] = first;
494 stream_Read (s, block->p_buffer + 2, datalen - 1);
497 block->i_dts = block->i_pts = date_Get (&p_demux->p_sys->pts);
498 es_out_Send (p_demux->out, p_demux->p_sys->es, block);
502 /* If event is not real-time, update running status */
503 tr->running_event = event;
505 tr->offset = stream_Tell (s);
509 /*****************************************************************************
510 * Demux: read chunks and send them to the synthetizer
511 *****************************************************************************
512 * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
513 *****************************************************************************/
514 static int Demux (demux_t *p_demux)
516 stream_t *s = p_demux->s;
517 demux_sys_t *p_sys = p_demux->p_sys;
518 uint64_t pulse = p_sys->pulse, next_pulse = UINT64_MAX;
520 if (pulse == UINT64_MAX)
521 return 0; /* all tracks are done */
523 es_out_Control (p_demux->out, ES_OUT_SET_PCR, date_Get (&p_sys->pts));
525 for (unsigned i = 0; i < p_sys->trackc; i++)
527 mtrk_t *track = p_sys->trackv + i;
529 while (track->next == pulse)
531 if (HandleMessage (p_demux, track)
532 || ReadDeltaTime (s, track))
534 msg_Err (p_demux, "fatal parsing error");
539 if (track->next < next_pulse)
540 next_pulse = track->next;
543 mtime_t cur_tick = (date_Get (&p_sys->pts) + 9999) / 10000, last_tick;
544 if (next_pulse != UINT64_MAX)
545 last_tick = date_Increment (&p_sys->pts, next_pulse - pulse) / 10000;
547 last_tick = cur_tick + 1;
549 /* MIDI Tick emulation (ping the decider every 10ms) */
550 while (cur_tick < last_tick)
552 block_t *tick = block_New (p_demux, 1);
556 tick->p_buffer[0] = 0xF9;
557 tick->i_dts = tick->i_pts = cur_tick++ * 10000;
558 es_out_Send (p_demux->out, p_sys->es, tick);
561 p_sys->pulse = next_pulse;
567 /*****************************************************************************
569 *****************************************************************************/
570 static int Control (demux_t *p_demux, int i_query, va_list args)
572 return demux2_vaControlHelper (p_demux->s, 0, -1, 0, 1, i_query, args);