Moved pre-processing step to Vision class (#25)

Lobe_iOS.xcodeproj/project.pbxproj

@@ -89,8 +89,8 @@
 		9B7B03DE2475DBF300D34020 = {
 			isa = PBXGroup;
 			children = (
-				B5B2D938260A4D5B00BABFAB /* LobeModel.mlmodel */,
 				9B7B03E92475DBF300D34020 /* Lobe_iOS */,
+				B5B2D938260A4D5B00BABFAB /* LobeModel.mlmodel */,
 				B513D84325809D62009D91E2 /* LobeTests */,
 				9B7B03E82475DBF300D34020 /* Products */,
 				B5A9B5252557373E00FD595B /* Frameworks */,

Lobe_iOS/Models/CaptureSessionManager.swift

@@ -174,19 +174,7 @@ extension UIImage {
   var isLandscape: Bool    { size.width > size.height }
   var breadth:     CGFloat { min(size.width, size.height) }
   var breadthSize: CGSize  { .init(width: breadth, height: breadth) }
-
-  func squared(isOpaque: Bool = false) -> UIImage? {
-    guard let cgImage = cgImage?
-            .cropping(to: .init(origin: .init(x: isLandscape ? ((size.width-size.height)/2).rounded(.down) : 0,
-                                              y: isPortrait  ? ((size.height-size.width)/2).rounded(.down) : 0),
-                                size: breadthSize)) else { return nil }
-    let format = imageRendererFormat
-    format.opaque = isOpaque
-    return UIGraphicsImageRenderer(size: breadthSize, format: format).image { _ in
-      UIImage(cgImage: cgImage, scale: 1, orientation: imageOrientation)
-        .draw(in: .init(origin: .zero, size: breadthSize))
-    }
-  }
+
   public convenience init?(pixelBuffer: CVPixelBuffer) {
     var cgImage: CGImage?
     VTCreateCGImageFromCVPixelBuffer(pixelBuffer, options: nil, imageOut: &cgImage)

Lobe_iOS/Models/PredictionLayer.swift

@@ -72,6 +72,11 @@ class PredictionLayer: NSObject {
       }
       onComplete(request)
     })
+
+    /// Set center cropping for the expected image size.
+    /// NOTE: Although center cropping is currently expected with Lobe's model version,
+    /// please be mindful of future changes which may affect the expected preprocessing steps.
+    request.imageCropAndScaleOption = .centerCrop
     return request
   }    
 }

Lobe_iOS/PlayViewModel.swift

@@ -37,11 +37,7 @@ class PlayViewModel: ObservableObject {
       .compactMap { $0 }  // remove non-nill values
       .receive(on: DispatchQueue.global(qos: .userInitiated))
       .sink(receiveValue: { [weak self] image in
-        guard let squaredImage = image.squared() else {
-          print("Could not create squared image in PlayViewModel.")
-          return
-        }
-        self?.imagePredicter.getPrediction(forImage: squaredImage)
+        self?.imagePredicter.getPrediction(forImage: image)
       })
       .store(in: &disposables)