Module mididi.reader

function MIDI readMIDIFile()(File file)

function MIDI readMIDIFile()(string path)

readMIDIFile() reads a MIDI file, of course.

This essentially does the same as MIDIReader!(ubyte[]).readMIDI(), but is given for convenience.

It has two overloads, one for std.stdio.File objects, and one if you have the file path only.

struct MIDIReader(T)

MIDIReader is the raw MIDI reader object.

This can be used to read the standard MIDI chunk-by-chunk or event-by-event.

Constraints: T must be an input range of ubyte

Example: Reads a complete file with a single track of a single event

import mididi.def : MetaEventType, TrackFormat;

auto reader = MIDIReader!(ubyte[])([
    'M', 'T', 'h', 'd', // header chunk
    0x00, 0x00, 0x00, 0x06, // length
    0x00, 0x01, // format 1
    0x00, 0x02, // 2 tracks
    0b0_0000000, 0x60, // time division: 0, 0, 0x60

    'M', 'T', 'r', 'k', // track chunk 1
    0, 0, 0, 4, // length = 4
    0x00, 0xFF, 0x2F, 0x00, // end of track

    'M', 'T', 'r', 'k', // track chunk 2
    0, 0, 0, 4, // length = 4
    0x00, 0xFF, 0x2F, 0x00, // end of track
]);
auto midi = reader.readMIDI();

assert(midi.headerChunk.trackFormat == TrackFormat.simultaneous);
assert(midi.headerChunk.nTracks == 2);
assert(midi.headerChunk.division.getFormat() == 0);
assert(midi.headerChunk.division.getTicksPerQuarterNote() == 0x0060);

assert(midi.trackChunks.length == 2);
assert(midi.trackChunks[0].events.length == 1);
const event = midi.trackChunks[0].events[0];
assert(event.asMetaEvent().type == MetaEventType.endOfTrack);

Example: Reads a file that has bytes past the last chunk, which is disallowed.

auto reader = MIDIReader!(ubyte[])([
    'M', 'T', 'h', 'd',
    0x00, 0x00, 0x00, 0x06, // length
    0x00, 0x00, // format: 0
    0x00, 0x01, // nTracks: 1
    0b0_0000000, 0x60, // time division: 0, 0, 0x60

    'M', 'T', 'r', 'k',
    0, 0, 0, 4,
    0x00, 0xFF, 0x2F, 0x00,

    'M', 'T', 'r', 'k', // too many chunks
    0, 0, 0, 4,
    0x00, 0xFF, 0x2F, 0x00,
]);

try {
    const _ = reader.readMIDI();
    assert(false, "File is invalid, but no exception was thrown");
} catch (Exception e) {}