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XDCMay2019MiamiUSA

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/AVFoundation/Live Barcode Detection
Function:
You find this example project in your Plugins Download as a Xojo project file within the examples folder: /AVFoundation/Live Barcode Detection
This example is the version from Thu, 29th Aug 2018.
Project "Live Barcode Detection.rbp"
Class App Inherits Application
Const kEditClear = "&Löschen"
Const kFileQuit = "Beenden"
Const kFileQuitShortcut = ""
EventHandler Sub Open() if AVFoundation.available = false then MsgBox "Please run on Mac OS X 10.7 or newer." quit end if AVFoundation = new MyAVFoundationMBS End EventHandler
Property AVFoundation As MyAVFoundationMBS
End Class
Class MainWindow Inherits Window
Control OutputCanvas Inherits Canvas
ControlInstance OutputCanvas Inherits Canvas
End Control
Control List Inherits Listbox
ControlInstance List Inherits Listbox
End Control
EventHandler Sub Close() app.AVFoundation.Win = nil if session<>nil then session.stopRunning session = nil end if window = nil End EventHandler
EventHandler Sub Open() configure End EventHandler
Sub Configure() // Create a capture session session = new AVCaptureSessionMBS // Set the session preset dim preset as string = AVFoundationMBS.AVCaptureSessionPreset640x480 session.SessionPreset = preset dim error as NSErrorMBS // Find video devices dim device as AVCaptureDeviceMBS = AVCaptureDeviceMBS.defaultDeviceWithMediaType(AVFoundationMBS.AVMediaTypeVideo) if device = nil then device = AVCaptureDeviceMBS.defaultDeviceWithMediaType(AVFoundationMBS.AVMediaTypeMuxed) end if if device = nil then MsgBox "No device found for video!" return end if // Create a device input with the device and add it to the session input = AVCaptureDeviceInputMBS.deviceInputWithDevice(device, error) if error<>Nil then MsgBox "deviceInputWithDevice: "+error.localizedDescription return end if session.addInputWithNoConnections input dim outputSettings as new Dictionary outputSettings.Value(AVFoundationMBS.AVVideoCodecKey) = AVFoundationMBS.AVVideoCodecJPEG StillImageOutput = new AVCaptureStillImageOutputMBS StillImageOutput.outputSettings = outputSettings session.addOutput StillImageOutput dim videoSettings as new Dictionary videoSettings.Value(CVPixelBufferMBS.kCVPixelBufferPixelFormatTypeKey) = CVPixelBufferMBS.kCVPixelFormatType_32ARGB ' e.g. kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange, ' kCVPixelFormatType_420YpCbCr8BiPlanarFullRange or ' kCVPixelFormatType_32BGRA. CIContext = New CIContextMBS CIDetector = new CIDetectorMBS(CIDetectorMBS.CIDetectorTypeQRCode, CIContext) BarcodeOutput = new AVCaptureVideoDataOutputMBS(CIDetector) BarcodeOutput.videoSettings = videoSettings BarcodeOutput.alwaysDiscardsLateVideoFrames = true app.AVFoundation.win = self session.addOutput BarcodeOutput // Attach preview to session previewViewLayer = outputCanvas.CALayerMBS previewViewLayer.BackgroundColor = CGColorMBS.Black newPreviewLayer = new AVCaptureVideoPreviewLayerMBS(session) newPreviewLayer.frame = previewViewLayer.bounds newPreviewLayer.autoresizingMask = newPreviewLayer.kCALayerWidthSizable + newPreviewLayer.kCALayerHeightSizable previewViewLayer.addSublayer newPreviewLayer session.startRunning End Sub
Property BarcodeOutput As AVCaptureVideoDataOutputMBS
Property CIContext As CIContextMBS
Property CIDetector As CIDetectorMBS
Property CurrentImage As NSImageMBS
Property LastTicks As Double
Property StillImageOutput As AVCaptureStillImageOutputMBS
Property currentPicture As Picture
Property devicesCount As Integer
Property input As AVCaptureDeviceInputMBS
Property newPreviewLayer As AVCaptureVideoPreviewLayerMBS
Property previewViewLayer As CALayerMBS
Property session As AVCaptureSessionMBS
Property window As NSWindowMBS
End Class
MenuBar MenuBar1
MenuItem FileMenu = "&Ablage"
MenuItem FileQuit = "#App.kFileQuit"
MenuItem EditMenu = "&Bearbeiten"
MenuItem EditUndo = "&Rückgängig"
MenuItem UntitledMenu1 = "-"
MenuItem EditCut = "&Ausschneiden"
MenuItem EditCopy = "&Kopieren"
MenuItem EditPaste = "&Einfügen"
MenuItem EditClear = "#App.kEditClear"
MenuItem UntitledMenu0 = "-"
MenuItem EditSelectAll = "&Alles auswählen"
End MenuBar
Class PhotoWindow Inherits Window
Control Output Inherits Canvas
ControlInstance Output Inherits Canvas
End Control
End Class
Class MyAVFoundationMBS Inherits AVFoundationMBS
EventHandler Sub captureOutputDidOutputSampleBuffer(captureOutput as AVCaptureOutputMBS, OutputSampleBuffer as CMSampleBufferMBS, connection as AVCaptureConnectionMBS, features as variant) if win <> nil and features <> nil then dim list as listbox = win.list list.DeleteAllRows dim cifeatures() as variant = features for each cifeature as CIFeatureMBS in cifeatures list.AddRow cifeature.type dim bounds as CGRectMBS = cifeature.bounds list.AddRow str(bounds.Left)+"/"+str(bounds.Top)+"-"+str(bounds.Width)+"/"+str(bounds.Height) if cifeature isa CIQRCodeFeatureMBS then dim f as CIQRCodeFeatureMBS = CIQRCodeFeatureMBS(cifeature) list.AddRow f.messageString end if next end if End EventHandler
EventHandler Sub captureStillImageAsynchronouslyCompleted(CaptureStillImageOutput as AVCaptureStillImageOutputMBS, prepareJpegStillImage as boolean, tag as variant, error as NSErrorMBS, imageDataSampleBuffer as CMSampleBufferMBS, JpegStillImage as memoryblock) dim pic as Picture = Picture.FromData(JpegStillImage) dim p as new PhotoWindow p.Backdrop = pic p.Width = pic.Width p.Height = pic.Height p.Left = MainWindow.Left + 20 + MainWindow.Width p.top = MainWindow.top p.show End EventHandler
Property win As MainWindow
End Class
End Project

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The items on this page are in the following plugins: MBS AVFoundation Plugin.




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