dls

Documentation

Overview

Package dls contains data structures for DLS (.dls) file types

Index

• type Art
• type DLS
• type ID
• type Ins
• type InsHeader
• type MIDILOCALE
• type PCMFormat
• type PoolTable
• type RGNRANGE
• type Rgn
• type RgnHeader
• type Wave
• type WaveLink
• type WaveSample
• type WaveSampleLoop

Types

type Art

type Art struct {
	// Todo: art1 doesn't fit our unmarshaler's expectations, because
	// it's basically its own type of subchunk with two sizes following
	// 'art1' then a number of structs based on the second size
	Art1 []byte `riff:"art1"`
}

An Art is something we need to look more into

type DLS

type DLS struct {
	Dlid      ID     `riff:"dlid"`
	Colh      uint32 `riff:"colh"`
	Vers      int64  `riff:"vers"`
	Lins      []Ins  `riff:"lins"`
	Ptbl      []byte `riff:"ptbl"` //PoolTable
	Wvpl      []Wave `riff:"wvpl"`
	riff.INFO `riff:"INFO"`
}

The DLS is the major struct we care about in this package DLS files contain instrument and wave sample information, and a bunch of other things users probably don't care about.

type ID

type ID struct {
	UlData1 uint32
	UlData2 uint16
	UlData3 uint16
	AbData4 [8]byte
}

An ID is a unique identifer for a dls file or instrument (or wave). This could just be written as a complex128.

type Ins

type Ins struct {
	Dlid      ID        `riff:"dlid"`
	Insh      InsHeader `riff:"insh"`
	Lrgn      []Rgn     `riff:"lrgn"`
	Lart      Art       `riff:"lart"`
	riff.INFO `riff:"INFO"`
}

An Ins holds instrument data

type InsHeader

type InsHeader struct {
	CRegions uint32
	Locale   MIDILOCALE
}

InsHeader stores header information for an instrument, notably the number of regions and the internal instrument bank and number

type MIDILOCALE

type MIDILOCALE struct {
	UlBank       uint32
	UlInstrument uint32
}

MIDILOCALE stores two of the fields in an instrument header

type PCMFormat

type PCMFormat struct {
	AudioFormat   uint16
	NumChannels   uint16
	SampleRate    uint32
	ByteRate      uint32
	BlockAlign    uint16
	BitsPerSample uint16
	WhoKnows      uint16 // Test files show there are buffer bytes here?
}

PCMFormat is a wave format that just know how many bits per sample a wave takes, beyond common format fields Really, there are two formats a Wave can take, this is just the one we hope to see. Todo: Fix that

type PoolTable

type PoolTable struct {
	CbSize uint32
	CCues  uint32
	// CCues size
	PoolCues []uint32
}

PoolTable is a goofy name for a thing that redirects references between instruments and waves, I think.

type RGNRANGE

type RGNRANGE struct {
	UsLow  uint16
	UsHigh uint16
}

An RGNRANGE just stores a low and a high value

type Rgn

type Rgn struct {
	Rgnh RgnHeader `riff:"rgnh"`
	Wsmp []byte    `riff:"wsmp"`
	Wlnk WaveLink  `riff:"wlnk"`
	Lart Art       `riff:"lart"`
}

Rgn is a region linking instruments to waves

type RgnHeader

type RgnHeader struct {
	RangeKey      RGNRANGE
	RangeVelocity RGNRANGE
	FusOptions    uint16
	UsKeyGroup    uint16
	UsLayer       uint16 // This field is optional
}

An RgnHeader stores header information for regions, notably for one the valid range of notes an instrument should be applied to Todo: figure out how to distinguish between rgnhs with and without ulLayer

type Wave

type Wave struct {
	Dlid ID        `riff:"dlid"`
	Guid []byte    `riff:"guid"`
	Wavu []byte    `riff:"wavu"`
	Fmt  PCMFormat `riff:"fmt "`
	Wavh []byte    `riff:"wavh"`
	Smpl []byte    `riff:"smpl"`
	Wsmp []byte    `riff:"wsmp"`
	// Data is the stuff you actually care about
	Data      []byte `riff:"data"`
	riff.INFO `riff:"INFO"`
}

Wave is the underlying struct you'd also find in WAV files. It stores raw audio information and headers describing how to play that information. The DLS Wave struct can also have a DLSID. Todo: Consider moving this out of this file entirely and into the WAV package, the downside of which would be that if a user wanted access to a DLSID it would no longer be there to get.

type WaveLink

type WaveLink struct {
	FusOptions   uint16
	UsPhaseGroup uint16
	UlChannel    uint32
	UlTableIndex uint32
}

WaveLink stores things I don't know about

type WaveSample

type WaveSample struct {
	CbSize      uint32
	UsUnityNote uint16
	SFineTune   int16
	LGain       int32
	FulOptions  uint32
	// As for art, WaveSampleLoop is CSampleLoops long
	CSampleLoops   uint32
	WaveSampleLoop []WaveSampleLoop
}

WaveSample also stores things I don't know about

type WaveSampleLoop

type WaveSampleLoop struct {
	CbSize       uint32
	UlLoopType   uint32
	UlLoopStart  uint32
	UlLoopLength uint32
}

WaveSampleLoop also stores things I don't know about