This is a Golang library to manipulate subtitles.

It allows you to manipulate srt, stl, ttml, ssa/ass, webvtt and teletext files for now.

Available operations are parsing, writing, applying linear correction, syncing, fragmenting, unfragmenting, merging and optimizing.

To install the library:

go get github.com/asticode/go-astisub

To install the CLI:

go install github.com/asticode/go-astisub/astisub        

WARNING: the code below doesn't handle errors for readibility purposes. However you SHOULD!

// Open subtitles
s1, _ := astisub.OpenFile("/path/to/example.ttml")
s2, _ := astisub.ReadFromSRT(bytes.NewReader([]byte("1\n00:01:00.000 --> 00:02:00.000\nCredits")))

// Add a duration to every subtitles (syncing)
s1.Add(-2*time.Second)

// Fragment the subtitles
s1.Fragment(2*time.Second)

// Merge subtitles
s1.Merge(s2)

// Optimize subtitles
s1.Optimize()

// Unfragment the subtitles
s1.Unfragment()

// Apply linear correction
s1.ApplyLinearCorrection(1*time.Second, 2*time.Second, 5*time.Second, 7*time.Second)

// Write subtitles
s1.Write("/path/to/example.srt")
var buf = &bytes.Buffer{}
s2.WriteToTTML(buf)

If astisub has been installed properly you can:

• convert any type of subtitle to any other type of subtitle:

    astisub convert -i example.srt -o example.ttml
  

• apply linear correction to any type of subtitle:

    astisub apply-linear-correction -i example.srt -a1 1s -d1 2s -a2 5s -d2 7s -o example.out.srt
  

• fragment any type of subtitle:

    astisub fragment -i example.srt -f 2s -o example.out.srt
  

• merge any type of subtitle into any other type of subtitle:

    astisub merge -i example.srt -i example.ttml -o example.out.srt
  

• optimize any type of subtitle:

    astisub optimize -i example.srt -o example.out.srt
  

• unfragment any type of subtitle:

    astisub unfragment -i example.srt -o example.out.srt
  

• sync any type of subtitle:

    astisub sync -i example.srt -s "-2s" -o example.out.srt
  

• parsing
• writing
• syncing
• fragmenting/unfragmenting
• merging
• ordering
• optimizing
• linear correction
• .srt
• .ttml
• .vtt
• .stl
• .ssa/.ass
• .teletext
• .smi