scratch-screen-share/cleaned-up/gstreamer-simple-pipeline.lisp

48 lines
1.8 KiB
Common Lisp

;(load (sb-ext:posix-getenv "ASDF"))
(asdf:load-system 'cl-gobject-introspection)
(defpackage :gstreamer-simple-pipeline
(:use :cl)
(:export cast-with-videobox))
(in-package :gstreamer-simple-pipeline)
;; name wildly from
;; https://stackoverflow.com/questions/36296165/python-bindings-for-gstreamer-how-to-import-typelib
(defvar *gstreamer* (gir:require-namespace "Gst"))
;; let's generalize, when stream is not passed, use the testsrc
(defun cast-with-videobox (&optional stream-num)
(gir:invoke (*gstreamer* 'init) '())
(let* ((pipeline (gir:invoke (*gstreamer* "Pipeline" 'new) "video-pipeline"))
(source (gir:invoke (*gstreamer* "ElementFactory" 'make) (if stream-num
"pipewiresrc"
"videotestsrc") "source"))
(convert (gir:invoke (*gstreamer* "ElementFactory" 'make) "videoconvert" "convert"))
(box (gir:invoke (*gstreamer* "ElementFactory" 'make) "videobox" "box"))
(sink (gir:invoke (*gstreamer* "ElementFactory" 'make) "autovideosink" "sink")))
(when stream-num
;; Set pipewiresrc properties, such as the path
(setf (gir:property source 'path) (format nil "~A" stream-num)))
;; Add and link elements in the pipeline
(gir:invoke (pipeline 'add) source)
(gir:invoke (pipeline 'add) convert)
(gir:invoke (pipeline 'add) box)
(gir:invoke (pipeline 'add) sink)
(gir:invoke (source 'link) convert)
(gir:invoke (convert 'link) box)
(gir:invoke (box 'link) sink)
(gir:invoke (pipeline 'set-state) (gir:nget *gstreamer* "State" :playing))
;(format t ">> arhg ~A" (gir:property box 'top))
(defun move-video (top left)
(setf (gir:property box 'top) top
(gir:property box 'left) left))
;; Example: Move the video 10 pixels down and 20 pixels to the right
(move-video 100 200)
pipeline))
;; now this works, but padding is symmetrical