;; Threshold effect - convert to pure black and white
;; Usage: python3 plan.py effects/threshold.sexp -p level=128 | python3 execute.py - -d . -o output.mp4
;;
;; Parameters:
;;   level: threshold cutoff (0 to 255, default: 128)
;;          pixels below = black, above = white

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

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

  ;; Default parameter (overridden by -p level=N)
  (def level 128)

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