;; Brightness effect - adjust image brightness
;; Usage: python3 plan.py effects/brightness.sexp [-p amount=30] | python3 execute.py - -d . -o output.mp4
;;
;; Parameters:
;;   amount: brightness adjustment (-255 to 255, default: 30)
;;           negative = darker, positive = brighter

(recipe "brightness"
  :version "1.0"
  :encoding (:codec "libx264" :crf 20 :preset "medium" :audio-codec "aac" :fps 30)

  (effect brightness :path "sexp_effects/effects/brightness.sexp")

  ;; Default parameter (overridden by -p amount=N)
  (def amount 30)

  (def video (source :path "monday.webm"))
  (def clip (-> video (segment :start 0 :duration 10)))
  (def result (-> clip (effect brightness :amount amount)))
  result)