diff --git a/ML/CGImage+CVPixelBuffer.swift b/ML/CGImage+CVPixelBuffer.swift
index 358067c4..a0a729c0 100644
--- a/ML/CGImage+CVPixelBuffer.swift
+++ b/ML/CGImage+CVPixelBuffer.swift
@@ -2,97 +2,6 @@ import CoreGraphics
 import CoreImage
 import VideoToolbox
 
-extension CGImage {
-  /**
-    Converts the image to an ARGB `CVPixelBuffer`.
-  */
-  public func pixelBuffer() -> CVPixelBuffer? {
-    return pixelBuffer(width: width, height: height, orientation: .up)
-  }
-
-  /**
-    Resizes the image to `width` x `height` and converts it to an ARGB
-    `CVPixelBuffer`.
-  */
-  public func pixelBuffer(width: Int, height: Int,
-                          orientation: CGImagePropertyOrientation) -> CVPixelBuffer? {
-    return pixelBuffer(width: width, height: height,
-                       pixelFormatType: kCVPixelFormatType_32ARGB,
-                       colorSpace: CGColorSpaceCreateDeviceRGB(),
-                       alphaInfo: .noneSkipFirst,
-                       orientation: orientation)
-  }
-
-  /**
-    Converts the image to a grayscale `CVPixelBuffer`.
-  */
-  public func pixelBufferGray() -> CVPixelBuffer? {
-    return pixelBufferGray(width: width, height: height, orientation: .up)
-  }
-
-  /**
-    Resizes the image to `width` x `height` and converts it to a grayscale
-    `CVPixelBuffer`.
-  */
-  public func pixelBufferGray(width: Int, height: Int,
-                              orientation: CGImagePropertyOrientation) -> CVPixelBuffer? {
-    return pixelBuffer(width: width, height: height,
-                       pixelFormatType: kCVPixelFormatType_OneComponent8,
-                       colorSpace: CGColorSpaceCreateDeviceGray(),
-                       alphaInfo: .none,
-                       orientation: orientation)
-  }
-
-  /**
-    Resizes the image to `width` x `height` and converts it to a `CVPixelBuffer`
-    with the specified pixel format, color space, and alpha channel.
-  */
-  public func pixelBuffer(width: Int, height: Int,
-                          pixelFormatType: OSType,
-                          colorSpace: CGColorSpace,
-                          alphaInfo: CGImageAlphaInfo,
-                          orientation: CGImagePropertyOrientation) -> CVPixelBuffer? {
-
-    // TODO: If the orientation is not .up, then rotate the CGImage.
-    // See also: https://stackoverflow.com/a/40438893/
-    assert(orientation == .up)
-
-    var maybePixelBuffer: CVPixelBuffer?
-    let attrs = [kCVPixelBufferCGImageCompatibilityKey: kCFBooleanTrue,
-                 kCVPixelBufferCGBitmapContextCompatibilityKey: kCFBooleanTrue]
-    let status = CVPixelBufferCreate(kCFAllocatorDefault,
-                                     width,
-                                     height,
-                                     pixelFormatType,
-                                     attrs as CFDictionary,
-                                     &maybePixelBuffer)
-
-    guard status == kCVReturnSuccess, let pixelBuffer = maybePixelBuffer else {
-      return nil
-    }
-
-    let flags = CVPixelBufferLockFlags(rawValue: 0)
-    guard kCVReturnSuccess == CVPixelBufferLockBaseAddress(pixelBuffer, flags) else {
-      return nil
-    }
-    defer { CVPixelBufferUnlockBaseAddress(pixelBuffer, flags) }
-
-    guard let context = CGContext(data: CVPixelBufferGetBaseAddress(pixelBuffer),
-                                  width: width,
-                                  height: height,
-                                  bitsPerComponent: 8,
-                                  bytesPerRow: CVPixelBufferGetBytesPerRow(pixelBuffer),
-                                  space: colorSpace,
-                                  bitmapInfo: alphaInfo.rawValue)
-    else {
-      return nil
-    }
-
-    context.draw(self, in: CGRect(x: 0, y: 0, width: width, height: height))
-    return pixelBuffer
-  }
-}
-
 extension CGImage {
   /**
     Creates a new CGImage from a CVPixelBuffer.
@@ -105,42 +14,4 @@ extension CGImage {
     VTCreateCGImageFromCVPixelBuffer(pixelBuffer, options: nil, imageOut: &cgImage)
     return cgImage
   }
-
-  /*
-  // Alternative implementation:
-  public static func create(pixelBuffer: CVPixelBuffer) -> CGImage? {
-    // This method creates a bitmap CGContext using the pixel buffer's memory.
-    // It currently only handles kCVPixelFormatType_32ARGB images. To support
-    // other pixel formats too, you'll have to change the bitmapInfo and maybe
-    // the color space for the CGContext.
-
-    guard kCVReturnSuccess == CVPixelBufferLockBaseAddress(pixelBuffer, .readOnly) else {
-      return nil
-    }
-    defer { CVPixelBufferUnlockBaseAddress(pixelBuffer, .readOnly) }
-
-    if let context = CGContext(data: CVPixelBufferGetBaseAddress(pixelBuffer),
-                               width: CVPixelBufferGetWidth(pixelBuffer),
-                               height: CVPixelBufferGetHeight(pixelBuffer),
-                               bitsPerComponent: 8,
-                               bytesPerRow: CVPixelBufferGetBytesPerRow(pixelBuffer),
-                               space: CGColorSpaceCreateDeviceRGB(),
-                               bitmapInfo: CGImageAlphaInfo.noneSkipFirst.rawValue),
-       let cgImage = context.makeImage() {
-      return cgImage
-    } else {
-      return nil
-    }
-  }
-  */
-
-  /**
-   Creates a new CGImage from a CVPixelBuffer, using Core Image.
-  */
-  public static func create(pixelBuffer: CVPixelBuffer, context: CIContext) -> CGImage? {
-    let ciImage = CIImage(cvPixelBuffer: pixelBuffer)
-    let rect = CGRect(x: 0, y: 0, width: CVPixelBufferGetWidth(pixelBuffer),
-                                  height: CVPixelBufferGetHeight(pixelBuffer))
-    return context.createCGImage(ciImage, from: rect)
-  }
 }
diff --git a/ML/ImageClassifier.swift b/ML/ImageClassifier.swift
index 8d2160c3..56c95ad7 100644
--- a/ML/ImageClassifier.swift
+++ b/ML/ImageClassifier.swift
@@ -62,7 +62,7 @@ class ModelImageClassifier {
         }
 
         let boundingBox = face.boundingBox
-        
+
         let size = CGSize(
             width: boundingBox.width * image.size.width,
             height: boundingBox.height * image.size.height
@@ -71,7 +71,7 @@ class ModelImageClassifier {
             x: boundingBox.minX * image.size.width,
             y: (1 - boundingBox.minY) * image.size.height - size.height
         )
-        
+
         let faceRect = CGRect(origin: origin, size: size)
 
         guard let croppedImage = cgImage.cropping(to: faceRect) else {
diff --git a/ML/UIImage+CVPixelBuffer.swift b/ML/UIImage+CVPixelBuffer.swift
index aaf66769..206bd6b4 100644
--- a/ML/UIImage+CVPixelBuffer.swift
+++ b/ML/UIImage+CVPixelBuffer.swift
@@ -2,13 +2,6 @@ import UIKit
 import VideoToolbox
 
 extension UIImage {
-  /**
-    Converts the image to an ARGB `CVPixelBuffer`.
-  */
-  public func pixelBuffer() -> CVPixelBuffer? {
-    return pixelBuffer(width: Int(size.width), height: Int(size.height))
-  }
-
   /**
     Resizes the image to `width` x `height` and converts it to an ARGB
     `CVPixelBuffer`.
@@ -20,24 +13,6 @@ extension UIImage {
                        alphaInfo: .noneSkipFirst)
   }
 
-  /**
-    Converts the image to a grayscale `CVPixelBuffer`.
-  */
-  public func pixelBufferGray() -> CVPixelBuffer? {
-    return pixelBufferGray(width: Int(size.width), height: Int(size.height))
-  }
-
-  /**
-    Resizes the image to `width` x `height` and converts it to a grayscale
-    `CVPixelBuffer`.
-  */
-  public func pixelBufferGray(width: Int, height: Int) -> CVPixelBuffer? {
-    return pixelBuffer(width: width, height: height,
-                       pixelFormatType: kCVPixelFormatType_OneComponent8,
-                       colorSpace: CGColorSpaceCreateDeviceGray(),
-                       alphaInfo: .none)
-  }
-
   /**
     Resizes the image to `width` x `height` and converts it to a `CVPixelBuffer`
     with the specified pixel format, color space, and alpha channel.
@@ -101,24 +76,4 @@ extension UIImage {
       return nil
     }
   }
-
-  /*
-  // Alternative implementation:
-  public convenience init?(pixelBuffer: CVPixelBuffer) {
-    // This converts the image to a CIImage first and then to a UIImage.
-    // Does not appear to work on the simulator but is OK on the device.
-    self.init(ciImage: CIImage(cvPixelBuffer: pixelBuffer))
-  }
-  */
-
-  /**
-    Creates a new UIImage from a CVPixelBuffer, using a Core Image context.
-  */
-  public convenience init?(pixelBuffer: CVPixelBuffer, context: CIContext) {
-    if let cgImage = CGImage.create(pixelBuffer: pixelBuffer, context: context) {
-      self.init(cgImage: cgImage)
-    } else {
-      return nil
-    }
-  }
 }