QRCode/Barcode Scanner (using ZBar)

[Oliver13]

Code snippet to scan/readbarcodes via webcam. It depends on the ZBar lib command line tools (download from https://zbar.sourceforge.net/download.html).

Maybe someone could help to improve:
- remove the console window (starting with #PB_Program_Hide is no option, for you won't see the camera selector dialog, too)
- invoke the camera selector dialog
- show detection frame (as usually shown by zbarlib)
- use libzbar-0.dll instead of cmd line tool

Code: Select all

;- Scan Barcode using ZBar barcode cmdline tool
;- https://zbar.sourceforge.net/download.html
; Compile with option threadsafe enabled 

Structure tScan
  iMainWindow.i
  sResult.s
EndStructure

Enumeration #PB_Event_FirstCustomValue+$ff
  #event_qrcode  
EndEnumeration


Procedure ScanQRCode(*t.tscan)
  Define.RECT WinPos
  Define.l Scanner, ZBarHandle, SizeX, SizeY
  Protected sret$
  
  sparams$="--prescale="+WindowWidth(*t\iMainWindow)+"x"+WindowHeight(*t\iMainWindow)
  
  Scanner = RunProgram(GetPathPart(ProgramFilename())+"zbarcam.exe",sparams$,"",#PB_Program_Open | #PB_Program_Read)
  Delay(100)
  If IsProgram(scanner)
    SetParent_(ProgramID(Scanner),WindowID(*t\iMainWindow)) 
    
    While Not FindWindow_(0,"ZBar") And ProgramRunning(Scanner)
      Delay(10)
    Wend
  EndIf
  ZBarHandle = FindWindow_(0,"ZBar")
  
  
  SetWindowLongPtr_(ZBarHandle, #GWL_STYLE, GetWindowLongPtr_(ZBarHandle, #GWL_STYLE) ! (#WS_DLGFRAME | #WS_BORDER | #WS_SIZEBOX))
  SetParent_(ZBarHandle,WindowID(*t\iMainWindow)) 
  MoveWindow_(ZBarHandle,0,0,WindowWidth(*t\iMainWindow),WindowHeight(*t\iMainWindow),#True)
  ;ShowWindow_(ZBarHandle,#SW_SHOWNORMAL)
  If IsProgram(scanner)
    While ProgramRunning(Scanner)
      If AvailableProgramOutput(Scanner)
        sret$ =ReadProgramString(Scanner)
        If StringField(UCase(sret$),1,":")="QR-CODE"
          sret$=Right(sret$,Len(sret$)-8)
          *t\sResult=sret$
          Beep_(100,100)
          PostEvent(#event_qrcode ,*t\iMainWindow,#Null)
          
        EndIf
        
        
      EndIf	
      If IsWindow(*t\iMainWindow)=#False
        
        Break
      EndIf
      
    Wend
    
    If IsProgram(scanner)
      KillProgram(scanner)
    EndIf
  EndIf
  
  CloseWindow_(ZBarHandle)
  
  
EndProcedure

Define tScanInfo.tScan

iScannerWindow=OpenWindow(#PB_Any,0,0,640,480,"Barcode Scannen",#PB_Window_ScreenCentered|#PB_Window_SystemMenu)
tScanInfo\imainwindow=iScannerWindow
CreateThread(@Scanqrcode(),@tScanInfo)

Repeat
  Event = WaitWindowEvent(1)
  
  Select Event
    Case #event_qrcode
      Debug tScanInfo\sResult
      
    Case #PB_Event_CloseWindow
      CloseWindow(iScannerWindow)
      bExit=1
      
      
  EndSelect
  
Until bExit=#True

[minimy]

Hello Oliver13. Try with this

Code: Select all

  Scanner = RunProgram(GetPathPart(ProgramFilename())+"zbarcam.exe",sparams$,"",#PB_Program_Open | #PB_Program_Read | #PB_Program_Hide)