J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2003-2007 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.media.sound; |
| 27 | |
| 28 | import javax.sound.midi.*; |
| 29 | import java.util.ArrayList; |
| 30 | |
| 31 | // TODO: |
| 32 | // - define and use a global symbolic constant for 60000000 (see convertTempo) |
| 33 | |
| 34 | /** |
| 35 | * Some utilities for MIDI (some stuff is used from javax.sound.midi) |
| 36 | * |
| 37 | * @author Florian Bomers |
| 38 | */ |
| 39 | public class MidiUtils { |
| 40 | |
| 41 | public final static int DEFAULT_TEMPO_MPQ = 500000; // 120bpm |
| 42 | public final static int META_END_OF_TRACK_TYPE = 0x2F; |
| 43 | public final static int META_TEMPO_TYPE = 0x51; |
| 44 | |
| 45 | |
| 46 | /** return true if the passed message is Meta End Of Track */ |
| 47 | public static boolean isMetaEndOfTrack(MidiMessage midiMsg) { |
| 48 | // first check if it is a META message at all |
| 49 | if (midiMsg.getLength() != 3 |
| 50 | || midiMsg.getStatus() != MetaMessage.META) { |
| 51 | return false; |
| 52 | } |
| 53 | // now get message and check for end of track |
| 54 | byte[] msg = midiMsg.getMessage(); |
| 55 | return ((msg[1] & 0xFF) == META_END_OF_TRACK_TYPE) && (msg[2] == 0); |
| 56 | } |
| 57 | |
| 58 | |
| 59 | /** return if the given message is a meta tempo message */ |
| 60 | public static boolean isMetaTempo(MidiMessage midiMsg) { |
| 61 | // first check if it is a META message at all |
| 62 | if (midiMsg.getLength() != 6 |
| 63 | || midiMsg.getStatus() != MetaMessage.META) { |
| 64 | return false; |
| 65 | } |
| 66 | // now get message and check for tempo |
| 67 | byte[] msg = midiMsg.getMessage(); |
| 68 | // meta type must be 0x51, and data length must be 3 |
| 69 | return ((msg[1] & 0xFF) == META_TEMPO_TYPE) && (msg[2] == 3); |
| 70 | } |
| 71 | |
| 72 | |
| 73 | /** parses this message for a META tempo message and returns |
| 74 | * the tempo in MPQ, or -1 if this isn't a tempo message |
| 75 | */ |
| 76 | public static int getTempoMPQ(MidiMessage midiMsg) { |
| 77 | // first check if it is a META message at all |
| 78 | if (midiMsg.getLength() != 6 |
| 79 | || midiMsg.getStatus() != MetaMessage.META) { |
| 80 | return -1; |
| 81 | } |
| 82 | byte[] msg = midiMsg.getMessage(); |
| 83 | if (((msg[1] & 0xFF) != META_TEMPO_TYPE) || (msg[2] != 3)) { |
| 84 | return -1; |
| 85 | } |
| 86 | int tempo = (msg[5] & 0xFF) |
| 87 | | ((msg[4] & 0xFF) << 8) |
| 88 | | ((msg[3] & 0xFF) << 16); |
| 89 | return tempo; |
| 90 | } |
| 91 | |
| 92 | |
| 93 | /** |
| 94 | * converts<br> |
| 95 | * 1 - MPQ-Tempo to BPM tempo<br> |
| 96 | * 2 - BPM tempo to MPQ tempo<br> |
| 97 | */ |
| 98 | public static double convertTempo(double tempo) { |
| 99 | if (tempo <= 0) { |
| 100 | tempo = 1; |
| 101 | } |
| 102 | return ((double) 60000000l) / tempo; |
| 103 | } |
| 104 | |
| 105 | |
| 106 | /** |
| 107 | * convert tick to microsecond with given tempo. |
| 108 | * Does not take tempo changes into account. |
| 109 | * Does not work for SMPTE timing! |
| 110 | */ |
| 111 | public static long ticks2microsec(long tick, double tempoMPQ, int resolution) { |
| 112 | return (long) (((double) tick) * tempoMPQ / resolution); |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * convert tempo to microsecond with given tempo |
| 117 | * Does not take tempo changes into account. |
| 118 | * Does not work for SMPTE timing! |
| 119 | */ |
| 120 | public static long microsec2ticks(long us, double tempoMPQ, int resolution) { |
| 121 | // do not round to nearest tick |
| 122 | //return (long) Math.round((((double)us) * resolution) / tempoMPQ); |
| 123 | return (long) ((((double)us) * resolution) / tempoMPQ); |
| 124 | } |
| 125 | |
| 126 | |
| 127 | /** |
| 128 | * Given a tick, convert to microsecond |
| 129 | * @param cache tempo info and current tempo |
| 130 | */ |
| 131 | public static long tick2microsecond(Sequence seq, long tick, TempoCache cache) { |
| 132 | if (seq.getDivisionType() != Sequence.PPQ ) { |
| 133 | double seconds = ((double)tick / (double)(seq.getDivisionType() * seq.getResolution())); |
| 134 | return (long) (1000000 * seconds); |
| 135 | } |
| 136 | |
| 137 | if (cache == null) { |
| 138 | cache = new TempoCache(seq); |
| 139 | } |
| 140 | |
| 141 | int resolution = seq.getResolution(); |
| 142 | |
| 143 | long[] ticks = cache.ticks; |
| 144 | int[] tempos = cache.tempos; // in MPQ |
| 145 | int cacheCount = tempos.length; |
| 146 | |
| 147 | // optimization to not always go through entire list of tempo events |
| 148 | int snapshotIndex = cache.snapshotIndex; |
| 149 | int snapshotMicro = cache.snapshotMicro; |
| 150 | |
| 151 | // walk through all tempo changes and add time for the respective blocks |
| 152 | long us = 0; // microsecond |
| 153 | |
| 154 | if (snapshotIndex <= 0 |
| 155 | || snapshotIndex >= cacheCount |
| 156 | || ticks[snapshotIndex] > tick) { |
| 157 | snapshotMicro = 0; |
| 158 | snapshotIndex = 0; |
| 159 | } |
| 160 | if (cacheCount > 0) { |
| 161 | // this implementation needs a tempo event at tick 0! |
| 162 | int i = snapshotIndex + 1; |
| 163 | while (i < cacheCount && ticks[i] <= tick) { |
| 164 | snapshotMicro += ticks2microsec(ticks[i] - ticks[i - 1], tempos[i - 1], resolution); |
| 165 | snapshotIndex = i; |
| 166 | i++; |
| 167 | } |
| 168 | us = snapshotMicro |
| 169 | + ticks2microsec(tick - ticks[snapshotIndex], |
| 170 | tempos[snapshotIndex], |
| 171 | resolution); |
| 172 | } |
| 173 | cache.snapshotIndex = snapshotIndex; |
| 174 | cache.snapshotMicro = snapshotMicro; |
| 175 | return us; |
| 176 | } |
| 177 | |
| 178 | /** |
| 179 | * Given a microsecond time, convert to tick. |
| 180 | * returns tempo at the given time in cache.getCurrTempoMPQ |
| 181 | */ |
| 182 | public static long microsecond2tick(Sequence seq, long micros, TempoCache cache) { |
| 183 | if (seq.getDivisionType() != Sequence.PPQ ) { |
| 184 | double dTick = ( ((double) micros) |
| 185 | * ((double) seq.getDivisionType()) |
| 186 | * ((double) seq.getResolution())) |
| 187 | / ((double) 1000000); |
| 188 | long tick = (long) dTick; |
| 189 | if (cache != null) { |
| 190 | cache.currTempo = (int) cache.getTempoMPQAt(tick); |
| 191 | } |
| 192 | return tick; |
| 193 | } |
| 194 | |
| 195 | if (cache == null) { |
| 196 | cache = new TempoCache(seq); |
| 197 | } |
| 198 | long[] ticks = cache.ticks; |
| 199 | int[] tempos = cache.tempos; // in MPQ |
| 200 | int cacheCount = tempos.length; |
| 201 | |
| 202 | int resolution = seq.getResolution(); |
| 203 | |
| 204 | long us = 0; long tick = 0; int newReadPos = 0; int i = 1; |
| 205 | |
| 206 | // walk through all tempo changes and add time for the respective blocks |
| 207 | // to find the right tick |
| 208 | if (micros > 0 && cacheCount > 0) { |
| 209 | // this loop requires that the first tempo Event is at time 0 |
| 210 | while (i < cacheCount) { |
| 211 | long nextTime = us + ticks2microsec(ticks[i] - ticks[i - 1], |
| 212 | tempos[i - 1], resolution); |
| 213 | if (nextTime > micros) { |
| 214 | break; |
| 215 | } |
| 216 | us = nextTime; |
| 217 | i++; |
| 218 | } |
| 219 | tick = ticks[i - 1] + microsec2ticks(micros - us, tempos[i - 1], resolution); |
| 220 | if (Printer.debug) Printer.debug("microsecond2tick(" + (micros / 1000)+") = "+tick+" ticks."); |
| 221 | //if (Printer.debug) Printer.debug(" -> convert back = " + (tick2microsecond(seq, tick, null) / 1000)+" microseconds"); |
| 222 | } |
| 223 | cache.currTempo = tempos[i - 1]; |
| 224 | return tick; |
| 225 | } |
| 226 | |
| 227 | |
| 228 | /** |
| 229 | * Binary search for the event indexes of the track |
| 230 | * |
| 231 | * @param tick - tick number of index to be found in array |
| 232 | * @return index in track which is on or after "tick". |
| 233 | * if no entries are found that follow after tick, track.size() is returned |
| 234 | */ |
| 235 | public static int tick2index(Track track, long tick) { |
| 236 | int ret = 0; |
| 237 | if (tick > 0) { |
| 238 | int low = 0; |
| 239 | int high = track.size() - 1; |
| 240 | while (low < high) { |
| 241 | // take the middle event as estimate |
| 242 | ret = (low + high) >> 1; |
| 243 | // tick of estimate |
| 244 | long t = track.get(ret).getTick(); |
| 245 | if (t == tick) { |
| 246 | break; |
| 247 | } else if (t < tick) { |
| 248 | // estimate too low |
| 249 | if (low == high - 1) { |
| 250 | // "or after tick" |
| 251 | ret++; |
| 252 | break; |
| 253 | } |
| 254 | low = ret; |
| 255 | } else { // if (t>tick) |
| 256 | // estimate too high |
| 257 | high = ret; |
| 258 | } |
| 259 | } |
| 260 | } |
| 261 | return ret; |
| 262 | } |
| 263 | |
| 264 | |
| 265 | public static class TempoCache { |
| 266 | long[] ticks; |
| 267 | int[] tempos; // in MPQ |
| 268 | // index in ticks/tempos at the snapshot |
| 269 | int snapshotIndex = 0; |
| 270 | // microsecond at the snapshot |
| 271 | int snapshotMicro = 0; |
| 272 | |
| 273 | int currTempo; // MPQ, used as return value for microsecond2tick |
| 274 | |
| 275 | private boolean firstTempoIsFake = false; |
| 276 | |
| 277 | public TempoCache() { |
| 278 | // just some defaults, to prevents weird stuff |
| 279 | ticks = new long[1]; |
| 280 | tempos = new int[1]; |
| 281 | tempos[0] = DEFAULT_TEMPO_MPQ; |
| 282 | snapshotIndex = 0; |
| 283 | snapshotMicro = 0; |
| 284 | } |
| 285 | |
| 286 | public TempoCache(Sequence seq) { |
| 287 | this(); |
| 288 | refresh(seq); |
| 289 | } |
| 290 | |
| 291 | |
| 292 | public synchronized void refresh(Sequence seq) { |
| 293 | ArrayList list = new ArrayList(); |
| 294 | Track[] tracks = seq.getTracks(); |
| 295 | if (tracks.length > 0) { |
| 296 | // tempo events only occur in track 0 |
| 297 | Track track = tracks[0]; |
| 298 | int c = track.size(); |
| 299 | for (int i = 0; i < c; i++) { |
| 300 | MidiEvent ev = track.get(i); |
| 301 | MidiMessage msg = ev.getMessage(); |
| 302 | if (isMetaTempo(msg)) { |
| 303 | // found a tempo event. Add it to the list |
| 304 | list.add(ev); |
| 305 | } |
| 306 | } |
| 307 | } |
| 308 | int size = list.size() + 1; |
| 309 | firstTempoIsFake = true; |
| 310 | if ((size > 1) |
| 311 | && (((MidiEvent) list.get(0)).getTick() == 0)) { |
| 312 | // do not need to add an initial tempo event at the beginning |
| 313 | size--; |
| 314 | firstTempoIsFake = false; |
| 315 | } |
| 316 | ticks = new long[size]; |
| 317 | tempos = new int[size]; |
| 318 | int e = 0; |
| 319 | if (firstTempoIsFake) { |
| 320 | // add tempo 120 at beginning |
| 321 | ticks[0] = 0; |
| 322 | tempos[0] = DEFAULT_TEMPO_MPQ; |
| 323 | e++; |
| 324 | } |
| 325 | for (int i = 0; i < list.size(); i++, e++) { |
| 326 | MidiEvent evt = (MidiEvent) list.get(i); |
| 327 | ticks[e] = evt.getTick(); |
| 328 | tempos[e] = getTempoMPQ(evt.getMessage()); |
| 329 | } |
| 330 | snapshotIndex = 0; |
| 331 | snapshotMicro = 0; |
| 332 | } |
| 333 | |
| 334 | public int getCurrTempoMPQ() { |
| 335 | return currTempo; |
| 336 | } |
| 337 | |
| 338 | float getTempoMPQAt(long tick) { |
| 339 | return getTempoMPQAt(tick, -1.0f); |
| 340 | } |
| 341 | |
| 342 | synchronized float getTempoMPQAt(long tick, float startTempoMPQ) { |
| 343 | for (int i = 0; i < ticks.length; i++) { |
| 344 | if (ticks[i] > tick) { |
| 345 | if (i > 0) i--; |
| 346 | if (startTempoMPQ > 0 && i == 0 && firstTempoIsFake) { |
| 347 | return startTempoMPQ; |
| 348 | } |
| 349 | return (float) tempos[i]; |
| 350 | } |
| 351 | } |
| 352 | return tempos[tempos.length - 1]; |
| 353 | } |
| 354 | |
| 355 | } |
| 356 | } |