| /* |
| * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.media.sound; |
| |
| import javax.sound.midi.*; |
| import java.util.ArrayList; |
| |
| // TODO: |
| // - define and use a global symbolic constant for 60000000 (see convertTempo) |
| |
| /** |
| * Some utilities for MIDI (some stuff is used from javax.sound.midi) |
| * |
| * @author Florian Bomers |
| */ |
| public final class MidiUtils { |
| |
| public final static int DEFAULT_TEMPO_MPQ = 500000; // 120bpm |
| public final static int META_END_OF_TRACK_TYPE = 0x2F; |
| public final static int META_TEMPO_TYPE = 0x51; |
| |
| /** |
| * Suppresses default constructor, ensuring non-instantiability. |
| */ |
| private MidiUtils() { |
| } |
| |
| /** return true if the passed message is Meta End Of Track */ |
| public static boolean isMetaEndOfTrack(MidiMessage midiMsg) { |
| // first check if it is a META message at all |
| if (midiMsg.getLength() != 3 |
| || midiMsg.getStatus() != MetaMessage.META) { |
| return false; |
| } |
| // now get message and check for end of track |
| byte[] msg = midiMsg.getMessage(); |
| return ((msg[1] & 0xFF) == META_END_OF_TRACK_TYPE) && (msg[2] == 0); |
| } |
| |
| |
| /** return if the given message is a meta tempo message */ |
| public static boolean isMetaTempo(MidiMessage midiMsg) { |
| // first check if it is a META message at all |
| if (midiMsg.getLength() != 6 |
| || midiMsg.getStatus() != MetaMessage.META) { |
| return false; |
| } |
| // now get message and check for tempo |
| byte[] msg = midiMsg.getMessage(); |
| // meta type must be 0x51, and data length must be 3 |
| return ((msg[1] & 0xFF) == META_TEMPO_TYPE) && (msg[2] == 3); |
| } |
| |
| |
| /** parses this message for a META tempo message and returns |
| * the tempo in MPQ, or -1 if this isn't a tempo message |
| */ |
| public static int getTempoMPQ(MidiMessage midiMsg) { |
| // first check if it is a META message at all |
| if (midiMsg.getLength() != 6 |
| || midiMsg.getStatus() != MetaMessage.META) { |
| return -1; |
| } |
| byte[] msg = midiMsg.getMessage(); |
| if (((msg[1] & 0xFF) != META_TEMPO_TYPE) || (msg[2] != 3)) { |
| return -1; |
| } |
| int tempo = (msg[5] & 0xFF) |
| | ((msg[4] & 0xFF) << 8) |
| | ((msg[3] & 0xFF) << 16); |
| return tempo; |
| } |
| |
| |
| /** |
| * converts<br> |
| * 1 - MPQ-Tempo to BPM tempo<br> |
| * 2 - BPM tempo to MPQ tempo<br> |
| */ |
| public static double convertTempo(double tempo) { |
| if (tempo <= 0) { |
| tempo = 1; |
| } |
| return ((double) 60000000l) / tempo; |
| } |
| |
| |
| /** |
| * convert tick to microsecond with given tempo. |
| * Does not take tempo changes into account. |
| * Does not work for SMPTE timing! |
| */ |
| public static long ticks2microsec(long tick, double tempoMPQ, int resolution) { |
| return (long) (((double) tick) * tempoMPQ / resolution); |
| } |
| |
| /** |
| * convert tempo to microsecond with given tempo |
| * Does not take tempo changes into account. |
| * Does not work for SMPTE timing! |
| */ |
| public static long microsec2ticks(long us, double tempoMPQ, int resolution) { |
| // do not round to nearest tick |
| //return (long) Math.round((((double)us) * resolution) / tempoMPQ); |
| return (long) ((((double)us) * resolution) / tempoMPQ); |
| } |
| |
| |
| /** |
| * Given a tick, convert to microsecond |
| * @param cache tempo info and current tempo |
| */ |
| public static long tick2microsecond(Sequence seq, long tick, TempoCache cache) { |
| if (seq.getDivisionType() != Sequence.PPQ ) { |
| double seconds = ((double)tick / (double)(seq.getDivisionType() * seq.getResolution())); |
| return (long) (1000000 * seconds); |
| } |
| |
| if (cache == null) { |
| cache = new TempoCache(seq); |
| } |
| |
| int resolution = seq.getResolution(); |
| |
| long[] ticks = cache.ticks; |
| int[] tempos = cache.tempos; // in MPQ |
| int cacheCount = tempos.length; |
| |
| // optimization to not always go through entire list of tempo events |
| int snapshotIndex = cache.snapshotIndex; |
| int snapshotMicro = cache.snapshotMicro; |
| |
| // walk through all tempo changes and add time for the respective blocks |
| long us = 0; // microsecond |
| |
| if (snapshotIndex <= 0 |
| || snapshotIndex >= cacheCount |
| || ticks[snapshotIndex] > tick) { |
| snapshotMicro = 0; |
| snapshotIndex = 0; |
| } |
| if (cacheCount > 0) { |
| // this implementation needs a tempo event at tick 0! |
| int i = snapshotIndex + 1; |
| while (i < cacheCount && ticks[i] <= tick) { |
| snapshotMicro += ticks2microsec(ticks[i] - ticks[i - 1], tempos[i - 1], resolution); |
| snapshotIndex = i; |
| i++; |
| } |
| us = snapshotMicro |
| + ticks2microsec(tick - ticks[snapshotIndex], |
| tempos[snapshotIndex], |
| resolution); |
| } |
| cache.snapshotIndex = snapshotIndex; |
| cache.snapshotMicro = snapshotMicro; |
| return us; |
| } |
| |
| /** |
| * Given a microsecond time, convert to tick. |
| * returns tempo at the given time in cache.getCurrTempoMPQ |
| */ |
| public static long microsecond2tick(Sequence seq, long micros, TempoCache cache) { |
| if (seq.getDivisionType() != Sequence.PPQ ) { |
| double dTick = ( ((double) micros) |
| * ((double) seq.getDivisionType()) |
| * ((double) seq.getResolution())) |
| / ((double) 1000000); |
| long tick = (long) dTick; |
| if (cache != null) { |
| cache.currTempo = (int) cache.getTempoMPQAt(tick); |
| } |
| return tick; |
| } |
| |
| if (cache == null) { |
| cache = new TempoCache(seq); |
| } |
| long[] ticks = cache.ticks; |
| int[] tempos = cache.tempos; // in MPQ |
| int cacheCount = tempos.length; |
| |
| int resolution = seq.getResolution(); |
| |
| long us = 0; long tick = 0; int newReadPos = 0; int i = 1; |
| |
| // walk through all tempo changes and add time for the respective blocks |
| // to find the right tick |
| if (micros > 0 && cacheCount > 0) { |
| // this loop requires that the first tempo Event is at time 0 |
| while (i < cacheCount) { |
| long nextTime = us + ticks2microsec(ticks[i] - ticks[i - 1], |
| tempos[i - 1], resolution); |
| if (nextTime > micros) { |
| break; |
| } |
| us = nextTime; |
| i++; |
| } |
| tick = ticks[i - 1] + microsec2ticks(micros - us, tempos[i - 1], resolution); |
| if (Printer.debug) Printer.debug("microsecond2tick(" + (micros / 1000)+") = "+tick+" ticks."); |
| //if (Printer.debug) Printer.debug(" -> convert back = " + (tick2microsecond(seq, tick, null) / 1000)+" microseconds"); |
| } |
| cache.currTempo = tempos[i - 1]; |
| return tick; |
| } |
| |
| |
| /** |
| * Binary search for the event indexes of the track |
| * |
| * @param tick - tick number of index to be found in array |
| * @return index in track which is on or after "tick". |
| * if no entries are found that follow after tick, track.size() is returned |
| */ |
| public static int tick2index(Track track, long tick) { |
| int ret = 0; |
| if (tick > 0) { |
| int low = 0; |
| int high = track.size() - 1; |
| while (low < high) { |
| // take the middle event as estimate |
| ret = (low + high) >> 1; |
| // tick of estimate |
| long t = track.get(ret).getTick(); |
| if (t == tick) { |
| break; |
| } else if (t < tick) { |
| // estimate too low |
| if (low == high - 1) { |
| // "or after tick" |
| ret++; |
| break; |
| } |
| low = ret; |
| } else { // if (t>tick) |
| // estimate too high |
| high = ret; |
| } |
| } |
| } |
| return ret; |
| } |
| |
| |
| public static final class TempoCache { |
| long[] ticks; |
| int[] tempos; // in MPQ |
| // index in ticks/tempos at the snapshot |
| int snapshotIndex = 0; |
| // microsecond at the snapshot |
| int snapshotMicro = 0; |
| |
| int currTempo; // MPQ, used as return value for microsecond2tick |
| |
| private boolean firstTempoIsFake = false; |
| |
| public TempoCache() { |
| // just some defaults, to prevents weird stuff |
| ticks = new long[1]; |
| tempos = new int[1]; |
| tempos[0] = DEFAULT_TEMPO_MPQ; |
| snapshotIndex = 0; |
| snapshotMicro = 0; |
| } |
| |
| public TempoCache(Sequence seq) { |
| this(); |
| refresh(seq); |
| } |
| |
| |
| public synchronized void refresh(Sequence seq) { |
| ArrayList list = new ArrayList(); |
| Track[] tracks = seq.getTracks(); |
| if (tracks.length > 0) { |
| // tempo events only occur in track 0 |
| Track track = tracks[0]; |
| int c = track.size(); |
| for (int i = 0; i < c; i++) { |
| MidiEvent ev = track.get(i); |
| MidiMessage msg = ev.getMessage(); |
| if (isMetaTempo(msg)) { |
| // found a tempo event. Add it to the list |
| list.add(ev); |
| } |
| } |
| } |
| int size = list.size() + 1; |
| firstTempoIsFake = true; |
| if ((size > 1) |
| && (((MidiEvent) list.get(0)).getTick() == 0)) { |
| // do not need to add an initial tempo event at the beginning |
| size--; |
| firstTempoIsFake = false; |
| } |
| ticks = new long[size]; |
| tempos = new int[size]; |
| int e = 0; |
| if (firstTempoIsFake) { |
| // add tempo 120 at beginning |
| ticks[0] = 0; |
| tempos[0] = DEFAULT_TEMPO_MPQ; |
| e++; |
| } |
| for (int i = 0; i < list.size(); i++, e++) { |
| MidiEvent evt = (MidiEvent) list.get(i); |
| ticks[e] = evt.getTick(); |
| tempos[e] = getTempoMPQ(evt.getMessage()); |
| } |
| snapshotIndex = 0; |
| snapshotMicro = 0; |
| } |
| |
| public int getCurrTempoMPQ() { |
| return currTempo; |
| } |
| |
| float getTempoMPQAt(long tick) { |
| return getTempoMPQAt(tick, -1.0f); |
| } |
| |
| synchronized float getTempoMPQAt(long tick, float startTempoMPQ) { |
| for (int i = 0; i < ticks.length; i++) { |
| if (ticks[i] > tick) { |
| if (i > 0) i--; |
| if (startTempoMPQ > 0 && i == 0 && firstTempoIsFake) { |
| return startTempoMPQ; |
| } |
| return (float) tempos[i]; |
| } |
| } |
| return tempos[tempos.length - 1]; |
| } |
| |
| } |
| } |
