cleanup and trying to catch frames

cleaned-up/gstreamer-simple-pipeline.lisp

@@ -0,0 +1,47 @@
+;(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