Script Library: 1218 scripts
 

web-cam.r

Rebol [ title: "Web Cam" date: 29-june-2008 file: %web-cam.r author: Nick Antonaccio purpose: { An example demonstrating how to use the Windows API to access local web cam images. Taken from the tutorial at http://musiclessonz.com/rebol_tutorial.html } ] ; First, open the Dlls that contain the Windows api functions we want ; to use (to view webcam video, and to change window titles): avicap32.dll: load/library %avicap32.dll user32.dll: load/library %user32.dll ; Create Rebol function prototypes required to change window titles: ; (These functions are found in user32.dll, built in to Windows.) get-focus: make routine! [return: [int]] user32.dll "GetFocus" set-caption: make routine! [ hwnd [int] a [string!] return: [int] ] user32.dll "SetWindowTextA" ; Create Rebol function prototypes required to view the webcam: ; (also built in to Windows) find-window-by-class: make routine! [ ClassName [string!] WindowName [integer!] return: [integer!] ] user32.dll "FindWindowA" sendmessage: make routine! [ hWnd [integer!] val1 [integer!] val2 [integer!] val3 [integer!] return: [integer!] ] user32.dll "SendMessageA" sendmessage-file: make routine! [ hWnd [integer!] val1 [integer!] val2 [integer!] val3 [string!] return: [integer!] ] user32.dll "SendMessageA" cap: make routine! [ cap [string!] child-val1 [integer!] val2 [integer!] val3 [integer!] width [integer!] height [integer!] handle [integer!] val4 [integer!] return: [integer!] ] avicap32.dll "capCreateCaptureWindowA" ; Create the Rebol GUI window: view/new center-face layout/tight [ image 320x240 across btn "Take Snapshot" [ ; Run the dll functions that take a snapshot: sendmessage cap-result 1085 0 0 sendmessage-file cap-result 1049 0 "scrshot.bmp" ] btn "Exit" [ ; Run the dll functions that stop the video: sendmessage cap-result 1205 0 0 sendmessage cap-result 1035 0 0 free user32.dll quit ] ] ; Run the Dll functions that reset our Rebol GUI window title: ; (eliminates "REBOL - " in the title bar) hwnd-set-title: get-focus set-caption hwnd-set-title "Web Camera" ; Run the Dll functions that show the video: hwnd: find-window-by-class "REBOLWind" 0 cap-result: cap "cap" 1342177280 0 0 320 240 hwnd 0 sendmessage cap-result 1034 0 0 sendmessage cap-result 1077 1 0 sendmessage cap-result 1075 1 0 sendmessage cap-result 1074 1 0 sendmessage cap-result 1076 1 0 ; start the GUI: do-events
halt ;; to terminate script if DO'ne from webpage