video capture in blitz ?

Blitz3D Forums/Blitz3D Programming/video capture in blitz ?

b32 (Posted 2006) [#1]

Does anybody know how to preview a capture source in Blitz ? I want to connect a common camera to my PCTV capture card and display the input on the background of a 3d application.

markcw (Posted 2006) [#2]

does this help? http://www.blitzbasic.com/Community/posts.php?topic=61763

b32 (Posted 2006) [#3]

Yes, it was very helpful. Thanks a lot! After a few tries, I got this code to run with my webcam. I can't capture onto an image, but it opens an extra window and displays the capture preview on it. In case someone wants to run this, you need the .decls as described at the end of the program: ;----------------------------------------------------------------------------------------------------- ; Avicap32.dll test ;----------------------------------------------------------------------------------------------------- Const WM_USER = 1024 Const WS_CHILD = $40000000 Const WS_VISIBLE = $10000000 Const WM_CAP_START = WM_USER Const WM_CAP_SET_CALLBACK_FRAME = WM_CAP_START + 5 Const WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10 Const WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11 Const WM_CAP_SET_OVERLAY = WM_CAP_START + 51 Const WM_CAP_SET_PREVIEW = WM_CAP_START + 50 Const WM_CAP_SET_PREVIEWRATE = WM_CAP_START + 52 Const WM_CAP_SET_SCALE = WM_CAP_START + 53 ;----------------------------------------------------------------------------------------------------- ; Main Program ;----------------------------------------------------------------------------------------------------- Graphics3D 320, 240, 0, 2 SetBuffer BackBuffer() ;create window hWnd = MakeWindow("capture") ;convert window to capture window hWndC = capCreateCaptureWindow("cap", WS_CHILD + WS_VISIBLE, 0, 0, 320, 240, hWnd, 1) ;connect to capturedriver ApiSendMessage hWndC, WM_CAP_DRIVER_CONNECT, 0, 0 ;set capturedriver properties ApiSendMessage hWndC, WM_CAP_SET_SCALE, True, 0 ApiSendMessage hWndC, WM_CAP_SET_PREVIEW, True, 0 ApiSendMessage hWndC, WM_CAP_SET_PREVIEWRATE, 24, 0 Api_SetFocus SystemProperty$("AppHwnd") ;----------------------------------------------------------------------------------------------------- ; Main Loop ;----------------------------------------------------------------------------------------------------- While Not KeyHit(1) Cls Text 0, 0, "Please use ESC to end program.." Flip Wend ;disconnect to capturedriver ApiSendMessage hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0 ;destory child window Api_DestroyWindow hwnd End ;------------------------------------------------------------------------------------------------------- ; MakeWindow() ;------------------------------------------------------------------------------------------------------- ;creates a basic window Function MakeWindow%(name$) ;create empty bank b b = CreateBank(4) ;create child window window = api_CreateWindowEx(0, GetBlitzClassName$(), name$, $10000000, 0, 0, 320, 240, 0, 0, 0, b) ;free bank b FreeBank b ;show child window api_ShowWindow window, 1 ;return new window handle Return window End Function ;------------------------------------------------------------------------------------------------------- ; GetBlitzClassName$() ;------------------------------------------------------------------------------------------------------- ;get blitz class name Function GetBlitzClassName$() ;get blitz window handle Local hwnd = SystemProperty$("AppHwnd") ;create empty bank p p = CreateBank(255) ;get class name via API s = api_GetClassName(hwnd, p, 255) ;convert bank to string d$ = "" For i = 0 To 254 ;read char ok = PeekByte(p, i) ;if char is empty, exit loop If ok = 0 Then Exit ;add to "d$" d$ = d$ + Chr$(ok) Next ;release bank p FreeBank p Return d$ End Function ;----------------------------------------------------------------------------------------------------- ;insert these files into the \userlibs directory of Blitz ;ie in "C:\PROGRAM FILES\BLITZ3D\USERLIBS" ;----------------------------------------------------------------------------------------------------- ;------------------------------------------------------------------------------------------------------ ;avicap32.decls ;------------------------------------------------------------------------------------------------------ ;.lib "Avicap32.dll" ;capCreateCaptureWindow%(lpszWindowName$,dwStyle%,x%,y%,nWidth%,nHeight%,hWnd%,nID%):"capCreateCaptureWindowA" ;------------------------------------------------------------------------------------------------------ ;------------------------------------------------------------------------------------------------------ ;user32.decls ;------------------------------------------------------------------------------------------------------ ;.lib "user32.dll" ; ;apiSendMessage%(hwnd%, wMsg%, wParam%, lParam%) : "SendMessageA" ;api_SetFocus% (hwnd%) : "SetFocus" ;api_DestroyWindow% (hwnd%) : "DestroyWindow" ;api_CreateWindowEx% (dwExStyle%, lpClassName$, lpWindowName$, dwStyle%, x%, y%, nWidth%, nHeight%, hWndParent%, hMenu%, hInstance%, lpParam*) : "CreateWindowExA" ;api_ShowWindow% (hwnd%, nCmdShow%) : "ShowWindow" ;api_GetClassName% (hwnd%, lpClassName*, nMaxCount%) : "GetClassNameA" ;------------------------------------------------------------------------------------------------------ If you want to grab a frame to blitz, use: Const WM_CAP_EDIT_COPY = WM_CAP_START + 30 ApiSendMessage hWndC, WM_CAP_EDIT_COPY, 0, 0 And use MarkCW's PasteFromClipBoard function.