Adds vtt2srt script

- Original: https://github.com/tunggnu/WebVTT-to-SRT

vtt2srt

@@ -0,0 +1,52 @@
+#!/bin/php
+<?php
+
+/**
+ * Example command on Linux:
+ *   php webvtt2srt.php file.vtt [file.srt]
+ */
+// Check command line mode
+if (empty($argv) or $argc <2)
+{
+    exit ("vtt2srt file.vtt [file.srt]\n");
+}
+
+// Get file paths
+$webVttFile = $argv[1];
+
+// If srt filename was passed
+if ($argc > 2)
+{
+    $srtFile = $argv[2];
+}
+else
+{
+    $info = pathinfo($argv[1]);
+
+    $srtFile = ($info['dirname'] ? $info['dirname'] . DIRECTORY_SEPARATOR : '')
+        . $info['filename']
+        . '.srt';
+}
+
+// Read the WebVTT file content into an array of lines
+$lines = file($webVttFile);
+
+// Convert all timestamp lines
+// The first timestamp line is 3
+$length = count($lines);
+
+for ($index = 3; $index < $length; $index++)
+{
+    // A line is a timestamp line if the second line above it is an empty line
+    if ( trim($lines[$index - 2]) === '' )
+    {
+        $lines[$index] = str_replace('.', ',', $lines[$index]);
+    }
+}
+
+// Remove 2 first lines of WebVTT format
+unset($lines[0]);
+unset($lines[1]);
+
+// Concatenate all other lines into the result file
+file_put_contents($srtFile, implode('', $lines));