(defun hour-minute-seconds-to-milliseconds (input)
  "Convert a string of format 01:02:03 to milliseconds."
  (with-temp-buffer
    (insert input)
    (goto-char (point-min))
    (search-forward-regexp "\\([[:digit:]]+\\):\\([[:digit:]]+\\):\\([[:digit:]]+\\)")
    (let* ((hour          (string-to-number (match-string 1)))
           (minutes       (* 60 hour))
           (minute  (string-to-number (match-string 2)))
           (seconds (* 60 (+ minute minutes)))
           (second (string-to-number (match-string 3)))
           (total (+ second seconds)))
      (* 1000 total))))

(defun kill-ring-to-milliseconds ()
  (interactive)
  (insert (number-to-string (hour-minute-seconds-to-milliseconds (car kill-ring)))))

(defun convert-playlist ()
  (interactive)

  (goto-char (point-min))

  (with-no-warnings
    (while t
      (search-forward "|") ;; to ensure failure on when we have passed last item.
      (end-of-line)
      (search-backward "|")
      (forward-char)
      (forward-char)
      (kill-line)
      (kill-ring-to-milliseconds)
      (beginning-of-line)
      (let ((line-move-visual nil))
        (next-line nil nil)))))