webvtt

go-webvtt

A Go library for parsing WebVTT (Web Video Text Tracks) files.

Synopsis

package main

import (
	"fmt"
	"os"

	"github.com/Songmu/go-webvtt"
)

func main() {
	f, _ := os.Open("subtitles.vtt")
	defer f.Close()

	// Batch parsing - get all cues at once
	vtt, _ := webvtt.ParseAll(f)
	for _, cue := range vtt.Cues {
		fmt.Printf("[%v - %v] %s\n", cue.StartTime, cue.EndTime, cue.Voices[0].Text)
	}
}

// Stream parsing - process blocks one by one
f, _ := os.Open("subtitles.vtt")
defer f.Close()

for block, err := range webvtt.Parse(f) {
	if err != nil {
		log.Fatal(err)
	}
	switch b := block.(type) {
	case webvtt.Cue:
		fmt.Printf("Cue: %s\n", b.Voices[0].Text)
	case webvtt.Note:
		fmt.Printf("Note: %s\n", b.Text)
	}
}

Features

• Stream-first design with iter.Seq2 iterator
• Parses cues, notes, styles, and regions
• Supports both timestamp formats: HH:MM:SS.mmm and MM:SS.mmm
• Handles voice/speaker tags <v Speaker>text</v>
• Parses cue settings (position, align, line, size, vertical, region)

Installation

% go get github.com/Songmu/go-webvtt

API

// Stream API - returns an iterator of blocks (Cue, Note, Style, Region)
func Parse(r io.Reader) iter.Seq2[Block, error]

// Batch API - parses all cues into a WebVTT struct
func ParseAll(r io.Reader) (*WebVTT, error)

Author

Songmu