export function parseTimestamp(timestamp: string): number { const match = timestamp.match( /^(?:(\d{1,}):)?(\d{1,2}):(\d{1,2})[,.](\d{1,3})$/ ) if (!match) { throw new Error('Invalid SRT or VTT time format: "' + timestamp + '"') } const hours = match[1] ? parseInt(match[1], 10) * 3600000 : 0 const minutes = parseInt(match[2], 10) * 60000 const seconds = parseInt(match[3], 10) * 1000 const milliseconds = parseInt(match[4], 10) return hours + minutes + seconds + milliseconds }