README
¶
drumbeat
Drumbeat is a Go library to create/parse drum beat patterns.
Example
More information and documentation available at .
// define a pattern using text:
patterns := drumbeat.NewFromString(drumbeat.One16, `
[kick] {C1} x.x.......xx...x x.x.....x......x;
[snare] {D1} ....x.......x... ....x.......x...;
[hihat] {F#1} x.x.x.x.x.x.x.x. x.x.x.x.x.x.x.x.
`)
// convert to MIDI
f, err := os.Create("drumbeat.mid")
if err != nil {
log.Println("something wrong happened when creating the MIDI file", err)
os.Exit(1)
}
if err := drumbeat.ToMIDI(f, patterns...); err != nil {
log.Fatal(err)
}
f.Close()
// generate a PNG visualization
imgf, err := os.Create("drumbeat.png")
if err != nil {
log.Println("something wrong happened when creating the image file", err)
os.Exit(1)
}
if err := drumbeat.SaveAsPNG(imgf, patterns); err != nil {
log.Fatal(err)
}
imgf.Close()
Documentation
¶
Overview ¶
Package drumbeat is a Go library to create/parse drum beat patterns.
Index ¶
Examples ¶
Constants ¶
const ( // DefaultPPQN is the default amount of ticks per quarter notes. DefaultPPQN = uint16(96) )
Variables ¶
This section is empty.
Functions ¶
Types ¶
type GridRes ¶
type GridRes string
GridRes is the resolution of the grid for the pattern
func (GridRes) StepsInBeat ¶
StepsInBeat returns the number of steps to fill a beat
type Pattern ¶
type Pattern struct {
// Name of the pattern or instrument
Name string
// Steps are the values for each step 0.0 means no pulse, a pulse greater
// than 0 indicates the duration in beats of the pulse
Pulses Pulses
// Key indicates the MIDI key this pattern should be triggering. Useful when
// converting to MIDI
Key int
// PPQN is the amount of ticks per quarter note.
PPQN uint16
// Grid is the resolution of the pattern
Grid GridRes
// contains filtered or unexported fields
}
Pattern represent the content of a drum pattern/beat.
func FromMIDI ¶
FromMIDI converts the content of a MIDI file into drum beat patterns. Note that this is for drum patterns only, expect the unexpected if you use non drum sequences.
Example ¶
package main
import (
"fmt"
"log"
"os"
"github.com/mattetti/drumbeat"
)
func main() {
f, err := os.Open("fixtures/singlePattern.mid")
if err != nil {
log.Fatal(err)
}
defer f.Close()
patterns, err := drumbeat.FromMIDI(f)
if err != nil {
log.Fatalf("Failed to parse the MIDI file - %v", err)
}
// Default to 1/16th grid
fmt.Printf("%s: %s", patterns[0].Name, patterns[0].Pulses)
}
Output: C1: x.......x.......
func NewFromString ¶
NewFromString converts a string where `x` are converted into active pulses. The first argument is the resolution of the grid so we can define how many steps fit in a bar. Default velocity is 0.9
Multiple patterns can be provided if separated by a semi colon: `;`.
Example ¶
package main
import (
"fmt"
"log"
"os"
"github.com/mattetti/drumbeat"
)
func main() {
patterns := drumbeat.NewFromString(drumbeat.One16, `
[kick] {C1} x.x.......xx...x x.x.....x......x;
[snare] {D1} ....x.......x... ....x.......x...;
[hihat] {F#1} x.x.x.x.x.x.x.x. x.x.x.x.x.x.x.x.
`)
f, err := os.Create("drumbeat.mid")
if err != nil {
log.Println("something wrong happened when creating the MIDI file", err)
os.Exit(1)
}
if err := drumbeat.ToMIDI(f, patterns...); err != nil {
log.Fatal(err)
}
f.Close()
fmt.Println("drumbeat.mid generated")
imgf, err := os.Create("drumbeat.png")
if err != nil {
log.Println("something wrong happened when creating the image file", err)
os.Exit(1)
}
if err := drumbeat.SaveAsPNG(imgf, patterns); err != nil {
log.Fatal(err)
}
imgf.Close()
fmt.Println("drumbeat.png generated")
os.Remove(f.Name())
os.Remove(imgf.Name())
}
Output: drumbeat.mid generated drumbeat.png generated
func (*Pattern) ActivePulses ¶
func (*Pattern) Offset ¶
Offset offsets the slice of pulses by moving the pulses to the right by n positions.
Source Files
Directories