OpenShot Library | libopenshot-audio 0.2.0
juce_MidiFile.h
1
2/** @weakgroup juce_audio_basics-midi
3 * @{
4 */
5/*
6 ==============================================================================
7
8 This file is part of the JUCE library.
9 Copyright (c) 2017 - ROLI Ltd.
10
11 JUCE is an open source library subject to commercial or open-source
12 licensing.
13
14 The code included in this file is provided under the terms of the ISC license
15 http://www.isc.org/downloads/software-support-policy/isc-license. Permission
16 To use, copy, modify, and/or distribute this software for any purpose with or
17 without fee is hereby granted provided that the above copyright notice and
18 this permission notice appear in all copies.
19
20 JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
21 EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
22 DISCLAIMED.
23
24 ==============================================================================
25*/
26
27namespace juce
28{
29
30//==============================================================================
31/**
32 Reads/writes standard midi format files.
33
34 To read a midi file, create a MidiFile object and call its readFrom() method. You
35 can then get the individual midi tracks from it using the getTrack() method.
36
37 To write a file, create a MidiFile object, add some MidiMessageSequence objects
38 to it using the addTrack() method, and then call its writeTo() method to stream
39 it out.
40
41 @see MidiMessageSequence
42
43 @tags{Audio}
44*/
46{
47public:
48 //==============================================================================
49 /** Creates an empty MidiFile object. */
50 MidiFile();
51
52 /** Destructor. */
53 ~MidiFile();
54
55 /** Creates a copy of another MidiFile. */
56 MidiFile (const MidiFile&);
57
58 /** Copies from another MidiFile object */
59 MidiFile& operator= (const MidiFile&);
60
61 /** Creates a copy of another MidiFile. */
63
64 /** Copies from another MidiFile object */
65 MidiFile& operator= (MidiFile&&);
66
67 //==============================================================================
68 /** Returns the number of tracks in the file.
69 @see getTrack, addTrack
70 */
71 int getNumTracks() const noexcept;
72
73 /** Returns a pointer to one of the tracks in the file.
74 @returns a pointer to the track, or nullptr if the index is out-of-range
75 @see getNumTracks, addTrack
76 */
77 const MidiMessageSequence* getTrack (int index) const noexcept;
78
79 /** Adds a midi track to the file.
80 This will make its own internal copy of the sequence that is passed-in.
81 @see getNumTracks, getTrack
82 */
83 void addTrack (const MidiMessageSequence& trackSequence);
84
85 /** Removes all midi tracks from the file.
86 @see getNumTracks
87 */
88 void clear();
89
90 /** Returns the raw time format code that will be written to a stream.
91
92 After reading a midi file, this method will return the time-format that
93 was read from the file's header. It can be changed using the setTicksPerQuarterNote()
94 or setSmpteTimeFormat() methods.
95
96 If the value returned is positive, it indicates the number of midi ticks
97 per quarter-note - see setTicksPerQuarterNote().
98
99 It it's negative, the upper byte indicates the frames-per-second (but negative), and
100 the lower byte is the number of ticks per frame - see setSmpteTimeFormat().
101 */
102 short getTimeFormat() const noexcept;
103
104 /** Sets the time format to use when this file is written to a stream.
105
106 If this is called, the file will be written as bars/beats using the
107 specified resolution, rather than SMPTE absolute times, as would be
108 used if setSmpteTimeFormat() had been called instead.
109
110 @param ticksPerQuarterNote e.g. 96, 960
111 @see setSmpteTimeFormat
112 */
113 void setTicksPerQuarterNote (int ticksPerQuarterNote) noexcept;
114
115 /** Sets the time format to use when this file is written to a stream.
116
117 If this is called, the file will be written using absolute times, rather
118 than bars/beats as would be the case if setTicksPerBeat() had been called
119 instead.
120
121 @param framesPerSecond must be 24, 25, 29 or 30
122 @param subframeResolution the sub-second resolution, e.g. 4 (midi time code),
123 8, 10, 80 (SMPTE bit resolution), or 100. For millisecond
124 timing, setSmpteTimeFormat (25, 40)
125 @see setTicksPerBeat
126 */
127 void setSmpteTimeFormat (int framesPerSecond,
128 int subframeResolution) noexcept;
129
130 //==============================================================================
131 /** Makes a list of all the tempo-change meta-events from all tracks in the midi file.
132 Useful for finding the positions of all the tempo changes in a file.
133 @param tempoChangeEvents a list to which all the events will be added
134 */
135 void findAllTempoEvents (MidiMessageSequence& tempoChangeEvents) const;
136
137 /** Makes a list of all the time-signature meta-events from all tracks in the midi file.
138 Useful for finding the positions of all the tempo changes in a file.
139 @param timeSigEvents a list to which all the events will be added
140 */
141 void findAllTimeSigEvents (MidiMessageSequence& timeSigEvents) const;
142
143 /** Makes a list of all the time-signature meta-events from all tracks in the midi file.
144 @param keySigEvents a list to which all the events will be added
145 */
146 void findAllKeySigEvents (MidiMessageSequence& keySigEvents) const;
147
148 /** Returns the latest timestamp in any of the tracks.
149 (Useful for finding the length of the file).
150 */
151 double getLastTimestamp() const;
152
153 //==============================================================================
154 /** Reads a midi file format stream.
155
156 After calling this, you can get the tracks that were read from the file by using the
157 getNumTracks() and getTrack() methods.
158
159 The timestamps of the midi events in the tracks will represent their positions in
160 terms of midi ticks. To convert them to seconds, use the convertTimestampTicksToSeconds()
161 method.
162
163 @param sourceStream the source stream
164 @param createMatchingNoteOffs if true, any missing note-offs for previous note-ons will
165 be automatically added at the end of the file by calling
166 MidiMessageSequence::updateMatchedPairs on each track.
167
168 @returns true if the stream was read successfully
169 */
170 bool readFrom (InputStream& sourceStream, bool createMatchingNoteOffs = true);
171
172 /** Writes the midi tracks as a standard midi file.
173 The midiFileType value is written as the file's format type, which can be 0, 1
174 or 2 - see the midi file spec for more info about that.
175
176 @param destStream the destination stream
177 @param midiFileType the type of midi file
178
179 @returns true if the operation succeeded.
180 */
181 bool writeTo (OutputStream& destStream, int midiFileType = 1) const;
182
183 /** Converts the timestamp of all the midi events from midi ticks to seconds.
184
185 This will use the midi time format and tempo/time signature info in the
186 tracks to convert all the timestamps to absolute values in seconds.
187 */
188 void convertTimestampTicksToSeconds();
189
190private:
191 //==============================================================================
193 short timeFormat;
194
195 void readNextTrack (const uint8*, int, bool);
196 bool writeTrack (OutputStream&, const MidiMessageSequence&) const;
197
198 JUCE_LEAK_DETECTOR (MidiFile)
199};
200
201} // namespace juce
202
203/** @}*/
The base class for streams that read data.
Reads/writes standard midi format files.
A sequence of timestamped midi messages.
The base class for streams that write data to some kind of destination.
An array designed for holding objects.
#define JUCE_API
This macro is added to all JUCE public class declarations.