SrtParser\srtFile::convertEncoding PHP Метод

    private function convertEncoding()
    {
        $exec = array();
        exec('file -i "' . $this->filename . '"', $exec);
        $res_exec = explode('=', $exec[0]);
        if (empty($res_exec[1])) {
            throw new \Exception('Unable to detect file encoding.');
        }
        $this->encoding = $res_exec[1];
        $tmp_encoding = strtolower($this->encoding);
        switch ($tmp_encoding) {
            case 'unknown':
            case 'windows-1252':
            case 'iso-8859-1':
            case 'iso-8859-15':
            case 'us-ascii':
                $this->encoding = self::default_encoding;
                $this->file_content = self::cp1252_to_utf8($this->file_content);
                break;
            default:
                if (strtolower(substr($this->encoding, 0, 3)) == 'utf' && self::detect_utf_encoding($this->file_content)) {
                    $this->has_BOM = true;
                }
                if (strtolower(substr($this->encoding, 0, 7)) == 'unknown') {
                    $this->encoding = self::default_encoding;
                    $this->file_content = self::cp1252_to_utf8($this->file_content);
                } else {
                    $this->file_content = mb_convert_encoding($this->file_content, 'UTF-8', $this->encoding);
                }
                break;
        }
    }