Cache UIImage objects to avoid re-decoding images unnecessarily

Tusker.xcodeproj/project.pbxproj

@@ -112,6 +112,7 @@
 		D62D2424217ABF3F005076CC /* NSUserActivity+Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = D62D2423217ABF3F005076CC /* NSUserActivity+Extensions.swift */; };
 		D62D2426217ABF63005076CC /* UserActivityType.swift in Sources */ = {isa = PBXBuildFile; fileRef = D62D2425217ABF63005076CC /* UserActivityType.swift */; };
 		D62FF04823D7CDD700909D6E /* AttributedStringHelperTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D62FF04723D7CDD700909D6E /* AttributedStringHelperTests.swift */; };
+		D6311C5025B3765B00B27539 /* ImageDataCache.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6311C4F25B3765B00B27539 /* ImageDataCache.swift */; };
 		D6333B372137838300CE884A /* AttributedString+Helpers.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6333B362137838300CE884A /* AttributedString+Helpers.swift */; };
 		D6333B792139AEFD00CE884A /* Date+TimeAgo.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6333B782139AEFD00CE884A /* Date+TimeAgo.swift */; };
 		D63569E023908A8D003DD353 /* StatusState.swift in Sources */ = {isa = PBXBuildFile; fileRef = D60A4FFB238B726A008AC647 /* StatusState.swift */; };
@@ -468,6 +469,7 @@
 		D62D2423217ABF3F005076CC /* NSUserActivity+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "NSUserActivity+Extensions.swift"; sourceTree = "<group>"; };
 		D62D2425217ABF63005076CC /* UserActivityType.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UserActivityType.swift; sourceTree = "<group>"; };
 		D62FF04723D7CDD700909D6E /* AttributedStringHelperTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AttributedStringHelperTests.swift; sourceTree = "<group>"; };
+		D6311C4F25B3765B00B27539 /* ImageDataCache.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ImageDataCache.swift; sourceTree = "<group>"; };
 		D6333B362137838300CE884A /* AttributedString+Helpers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "AttributedString+Helpers.swift"; sourceTree = "<group>"; };
 		D6333B782139AEFD00CE884A /* Date+TimeAgo.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Date+TimeAgo.swift"; sourceTree = "<group>"; };
 		D63661BF2381C144004B9E16 /* PreferencesNavigationController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreferencesNavigationController.swift; sourceTree = "<group>"; };
@@ -1493,6 +1495,7 @@
 			children = (
 				D6F1F84C2193B56E00F5FE67 /* Cache.swift */,
 				04DACE8D212CC7CC009840C4 /* ImageCache.swift */,
+				D6311C4F25B3765B00B27539 /* ImageDataCache.swift */,
 			);
 			path = Caching;
 			sourceTree = "<group>";
@@ -1889,6 +1892,7 @@
 				D627943723A552C200D38C68 /* BookmarkStatusActivity.swift in Sources */,
 				D62D2426217ABF63005076CC /* UserActivityType.swift in Sources */,
 				D6AC956723C4347E008C9946 /* MainSceneDelegate.swift in Sources */,
+				D6311C5025B3765B00B27539 /* ImageDataCache.swift in Sources */,
 				D6BC9DD7232D7811002CA326 /* TimelinesPageViewController.swift in Sources */,
 				D60E2F2E244248BF005F8713 /* MastodonCachePersistentStore.swift in Sources */,
 				D620483623D38075008A63EF /* ContentTextView.swift in Sources */,

Tusker/Activities/AccountActivityItemSource.swift

@@ -29,7 +29,7 @@ class AccountActivityItemSource: NSObject, UIActivityItemSource {
         metadata.originalURL = account.url
         metadata.url = account.url
         metadata.title = "\(account.displayName) (@\(account.username)@\(account.url.host!)"
-        if let data = ImageCache.avatars.get(account.avatar),
+        if let data = ImageCache.avatars.getData(account.avatar),
             let image = UIImage(data: data) {
             metadata.iconProvider = NSItemProvider(object: image)
         }

Tusker/Activities/StatusActivityItemSource.swift

@@ -32,7 +32,7 @@ class StatusActivityItemSource: NSObject, UIActivityItemSource {
         let doc = try! SwiftSoup.parse(status.content)
         let content = try! doc.text()
         metadata.title = "\(status.account.displayName): \"\(content)\""
-        if let data = ImageCache.avatars.get(status.account.avatar),
+        if let data = ImageCache.avatars.getData(status.account.avatar),
             let image = UIImage(data: data) {
             metadata.iconProvider = NSItemProvider(object: image)
         }

Tusker/Caching/ImageCache.swift

@@ -22,47 +22,36 @@ class ImageCache {
     private static let disableCaching = false
     #endif
 
-    private let cache: Cache<Data>
+    private let cache: ImageDataCache
     
     private var groups = MultiThreadDictionary<URL, RequestGroup>(name: "ImageCache request groups")
     
     private var backgroundQueue = DispatchQueue(label: "ImageCache completion queue", qos: .default)
     
-    init(name: String, memoryExpiry expiry: Expiry) {
+    init(name: String, memoryExpiry: Expiry, diskExpiry: Expiry? = nil) {
-        let storage = MemoryStorage<Data>(config: MemoryConfig(expiry: expiry))
+        self.cache = ImageDataCache(name: name, memoryExpiry: memoryExpiry, diskExpiry: diskExpiry)
-        self.cache = .memory(storage)
     }
     
-    init(name: String, diskExpiry expiry: Expiry) {
+    func get(_ url: URL, completion: ((Data?, UIImage?) -> Void)?) -> Request? {
-        let storage = try! DiskStorage<Data>(config: DiskConfig(name: name, expiry: expiry), transformer: TransformerFactory.forData())
-        self.cache = .disk(storage)
-    }
-    
-    init(name: String, memoryExpiry: Expiry, diskExpiry: Expiry) {
-        let memory = MemoryStorage<Data>(config: MemoryConfig(expiry: memoryExpiry))
-        let disk = try! DiskStorage<Data>(config: DiskConfig(name: name, expiry: diskExpiry), transformer: TransformerFactory.forData())
-        self.cache = .hybrid(HybridStorage(memoryStorage: memory, diskStorage: disk))
-    }
-    
-    func get(_ url: URL, completion: ((Data?) -> Void)?) -> Request? {
         let key = url.absoluteString
         if !ImageCache.disableCaching,
            // todo: calling object(forKey: key) does disk I/O and this method is often called from the main thread
            // in performance sensitive paths. a nice optimization to DiskStorage would be adding an internal cache
            // of the state (unknown/exists/does not exist) of whether or not objects exist on disk so that the slow, disk I/O
            // path can be avoided most of the time
-           let data = try? cache.object(forKey: key) {
+           let (data, image) = try? cache.get(key) {
             backgroundQueue.async {
-                completion?(data)
+                completion?(data, image)
             }
             return nil
         } else {
             if let completion = completion, let group = groups[url] {
                 return group.addCallback(completion)
             } else {
-                let group = RequestGroup(url: url) { (data) in
+                let group = RequestGroup(url: url) { (data, image) in
-                    if let data = data {
+                    if let data = data,
-                        try? self.cache.setObject(data, forKey: key)
+                       let image = UIImage(data: data) {
+                        try? self.cache.set(key, data: data, image: image)
                     }
                     self.groups.removeValueWithoutReturning(forKey: url)
                 }
@@ -74,8 +63,12 @@ class ImageCache {
         }
     }
     
-    func get(_ url: URL) -> Data? {
+    func getData(_ url: URL) -> Data? {
-        return try? cache.object(forKey: url.absoluteString)
+        return try? cache.getData(url.absoluteString)
+    }
+    
+    func get(_ url: URL) -> (Data, UIImage)? {
+        return try? cache.get(url.absoluteString)
     }
 
     func cancelWithoutCallback(_ url: URL) {
@@ -88,11 +81,11 @@ class ImageCache {
     
     private class RequestGroup {
         let url: URL
-        private let onFinished: (Data?) -> Void
+        private let onFinished: (Data?, UIImage?) -> Void
         private var task: URLSessionDataTask?
         private var requests = [Request]()
 
-        init(url: URL, onFinished: @escaping (Data?) -> Void) {
+        init(url: URL, onFinished: @escaping (Data?, UIImage?) -> Void) {
             self.url = url
             self.onFinished = onFinished
         }
@@ -116,7 +109,7 @@ class ImageCache {
             task?.priority = max(1.0, URLSessionTask.defaultPriority + 0.1 * Float(requests.filter { !$0.cancelled }.count))
         }
         
-        func addCallback(_ completion: ((Data?) -> Void)?) -> Request {
+        func addCallback(_ completion: ((Data?, UIImage?) -> Void)?) -> Request {
             let request = Request(callback: completion)
             requests.append(request)
             updatePriority()
@@ -141,21 +134,24 @@ class ImageCache {
         }
 
         func complete(with data: Data?) {
+            let image = data != nil ? UIImage(data: data!) : nil
+            
             requests.filter { !$0.cancelled }.forEach {
                 if let callback = $0.callback {
-                    callback(data)
+                    callback(data, image)
                 }
             }
-            self.onFinished(data)
+            
+            self.onFinished(data, image)
         }
     }
     
     class Request {
         private weak var group: RequestGroup?
-        private(set) var callback: ((Data?) -> Void)?
+        private(set) var callback: ((Data?, UIImage?) -> Void)?
         private(set) var cancelled: Bool = false
         
-        init(callback: ((Data?) -> Void)?) {
+        init(callback: ((Data?, UIImage?) -> Void)?) {
             self.callback = callback
         }
         

Tusker/Caching/ImageDataCache.swift

@@ -0,0 +1,74 @@
+//
+//  ImageDataCache.swift
+//  Tusker
+//
+//  Created by Shadowfacts on 1/16/21.
+//  Copyright © 2021 Shadowfacts. All rights reserved.
+//
+
+import UIKit
+import Cache
+
+class ImageDataCache {
+    
+    private let memory: MemoryStorage<(Data, UIImage)>
+    private let disk: DiskStorage<Data>?
+    
+    init(name: String, memoryExpiry: Expiry, diskExpiry: Expiry?) {
+        let memoryConfig = MemoryConfig(expiry: memoryExpiry)
+        self.memory = MemoryStorage(config: memoryConfig)
+        
+        if let diskExpiry = diskExpiry {
+            let diskConfig = DiskConfig(name: name, expiry: diskExpiry)
+            self.disk = try! DiskStorage(config: diskConfig, transformer: TransformerFactory.forData())
+        } else {
+            self.disk = nil
+        }
+    }
+    
+    func has(_ key: String) throws -> Bool {
+        if try memory.existsObject(forKey: key) {
+            return true
+        } else if let disk = self.disk,
+                  try disk.existsObject(forKey: key) {
+            return true
+        } else {
+            return false
+        }
+    }
+    
+    func get(_ key: String) throws -> (Data, UIImage)? {
+        if try memory.existsObject(forKey: key) {
+            return try! memory.object(forKey: key)
+        } else if let disk = self.disk,
+                  try disk.existsObject(forKey: key),
+                  let data = try? disk.object(forKey: key),
+                  let image = UIImage(data: data) {
+            return (data, image)
+        } else {
+            return nil
+        }
+    }
+    
+    func getImage(_ key: String) throws -> UIImage? {
+        return try get(key)?.1
+    }
+    
+    func getData(_ key: String) throws -> Data? {
+        return try get(key)?.0
+    }
+    
+    func set(_ key: String, data: Data, image: UIImage) throws {
+        memory.setObject((data, image), forKey: key)
+        
+        if let disk = self.disk {
+            try disk.setObject(data, forKey: key)
+        }
+    }
+    
+    func removeAll() throws {
+        memory.removeAll()
+        try? disk?.removeAll()
+    }
+    
+}

Tusker/ImageGrayscalifier.swift

@@ -14,6 +14,15 @@ struct ImageGrayscalifier {
     private static let context = CIContext()
     private static let cache = NSCache<NSURL, UIImage>()
 
+    static func convertIfNecessary(url: URL?, image: UIImage) -> UIImage? {
+        if Preferences.shared.grayscaleImages,
+           let source = image.cgImage {
+            return convert(url: url, cgImage: source)
+        } else {
+            return image
+        }
+    }
+    
     static func convert(url: URL?, data: Data) -> UIImage? {
         if let url = url,
            let cached = cache.object(forKey: url as NSURL) {

Tusker/Screens/Attachment Gallery/AttachmentPreviewViewController.swift

@@ -25,7 +25,7 @@ class AttachmentPreviewViewController: UIViewController {
     }
     
     override func loadView() {
-        if let data = ImageCache.attachments.get(attachment.url),
+        if let data = ImageCache.attachments.getData(attachment.url),
             let image = UIImage(data: data) {
             let imageView: UIImageView
             if attachment.url.pathExtension == "gif" {

Tusker/Screens/Attachment Gallery/GalleryViewController.swift

@@ -44,7 +44,7 @@ class GalleryViewController: UIPageViewController, UIPageViewControllerDataSourc
     var animationGifData: Data? {
         let attachment = attachments[currentIndex]
         if attachment.url.pathExtension == "gif" {
-            return ImageCache.attachments.get(attachment.url)
+            return ImageCache.attachments.getData(attachment.url)
         } else {
             return nil
         }

Tusker/Screens/Compose/ComposeAvatarImageView.swift

@@ -44,16 +44,10 @@ struct ComposeAvatarImageView: View {
     
     private func loadImage() {
         guard let url = url else { return }
-        request = ImageCache.avatars.get(url) { (data) in
+        request = ImageCache.avatars.get(url) { (_, image) in
-            if let data = data, let image = UIImage(data: data) {
+            DispatchQueue.main.async {
-                DispatchQueue.main.async {
+                self.request = nil
-                    self.request = nil
+                self.avatarImage = image
-                    self.avatarImage = image
-                }
-            } else {
-                DispatchQueue.main.async {
-                    self.request = nil
-                }
             }
         }
     }

Tusker/Screens/Compose/EmojiCollectionViewCell.swift

@@ -45,12 +45,11 @@ class EmojiCollectionViewCell: UICollectionViewCell {
     func updateUI(emoji: Emoji) {
         currentEmojiShortcode = emoji.shortcode
         
-        imageRequest = ImageCache.emojis.get(emoji.url) { [weak self] (data) in
+        imageRequest = ImageCache.emojis.get(emoji.url) { [weak self] (_, image) in
-            if let data = data, let image = UIImage(data: data) {
+            guard let image = image else { return }
-                DispatchQueue.main.async { [weak self] in
+            DispatchQueue.main.async { [weak self] in
-                    guard let self = self, self.currentEmojiShortcode == emoji.shortcode else { return }
+                guard let self = self, self.currentEmojiShortcode == emoji.shortcode else { return }
-                    self.emojiImageView.image = image
+                self.emojiImageView.image = image
-                }
             }
         }
     }

Tusker/Screens/Fast Account Switcher/FastSwitchingAccountView.swift

@@ -87,8 +87,8 @@ class FastSwitchingAccountView: UIView {
         let controller = MastodonController.getForAccount(account)
         controller.getOwnAccount { [weak self] (result) in
             guard let self = self, case let .success(account) = result else { return }
-            self.avatarRequest = ImageCache.avatars.get(account.avatar) { [weak avatarImageView] (data) in
+            self.avatarRequest = ImageCache.avatars.get(account.avatar) { [weak avatarImageView] (_, image) in
-                guard let avatarImageView = avatarImageView, let data = data, let image = UIImage(data: data) else { return }
+                guard let avatarImageView = avatarImageView, let image = image else { return }
                 DispatchQueue.main.async {
                     avatarImageView.image = image
                 }

Tusker/Screens/Large Image/LoadingLargeImageViewController.swift

@@ -85,19 +85,19 @@ class LoadingLargeImageViewController: UIViewController, LargeImageAnimatableVie
         overrideUserInterfaceStyle = .dark
         view.backgroundColor = .black
         
-        if let data = cache.get(url) {
+        if let (data, image) = cache.get(url) {
-            createLargeImage(data: data, url: url)
+            createLargeImage(data: data, image: image, url: url)
         } else {
             createPreview()
             
             loadingVC = LoadingViewController()
             embedChild(loadingVC!)
-            imageRequest = cache.get(url) { [weak self] (data) in
+            imageRequest = cache.get(url) { [weak self] (data, image) in
                 guard let self = self else { return }
                 self.imageRequest = nil
                 DispatchQueue.main.async {
                     self.loadingVC?.removeViewAndController()
-                    self.createLargeImage(data: data!, url: self.url)
+                    self.createLargeImage(data: data!, image: image!, url: self.url)
                 }
             }
         }
@@ -115,20 +115,13 @@ class LoadingLargeImageViewController: UIViewController, LargeImageAnimatableVie
         }
     }
     
-    private func createLargeImage(data: Data, url: URL) {
+    private func createLargeImage(data: Data, image: UIImage, url: URL) {
         guard !loaded else { return }
         loaded = true
         
-        let image: UIImage?
+        if let transformedImage = ImageGrayscalifier.convertIfNecessary(url: url, image: image) {
-        if Preferences.shared.grayscaleImages {
-            image = ImageGrayscalifier.convert(url: url, data: data)
-        } else {
-            image = UIImage(data: data)
-        }
-        
-        if let image = image {
             let gifData = url.pathExtension == "gif" ? data : nil
-            createLargeImage(image: image, gifData: gifData)
+            createLargeImage(image: transformedImage, gifData: gifData)
         }
     }
     

Tusker/Screens/Preferences/LocalAccountAvatarView.swift

@@ -38,11 +38,9 @@ struct LocalAccountAvatarView: View {
         let controller = MastodonController.getForAccount(localAccountInfo)
         controller.getOwnAccount { (result) in
             guard case let .success(account) = result else { return }
-            _ = ImageCache.avatars.get(account.avatar) { (data) in
+            _ = ImageCache.avatars.get(account.avatar) { (_, image) in
-                if let data = data, let image = UIImage(data: data) {
+                DispatchQueue.main.async {
-                    DispatchQueue.main.async {
+                    self.avatarImage = image
-                        self.avatarImage = image
-                    }
                 }
             }
         }

Tusker/Screens/Profile/MyProfileViewController.swift

@@ -43,17 +43,10 @@ class MyProfileViewController: ProfileViewController {
     
     private func setAvatarTabBarImage<Account: AccountProtocol>(account: Account) {
         let avatarURL = account.avatar
-        _ = ImageCache.avatars.get(avatarURL, completion: { [weak self] (data) in
+        _ = ImageCache.avatars.get(avatarURL, completion: { [weak self] (_, image) in
-            guard let self = self, let data = data else { return }
+            guard let self = self,
-            
+                  let image = image,
-            let maybeGrayscale: UIImage?
+                  let maybeGrayscale = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else {
-            if Preferences.shared.grayscaleImages {
-                maybeGrayscale = ImageGrayscalifier.convert(url: avatarURL, data: data)
-            } else {
-                maybeGrayscale = UIImage(data: data)
-            }
-            
-            guard let image = maybeGrayscale else {
                 return
             }
             
@@ -63,7 +56,7 @@ class MyProfileViewController: ProfileViewController {
                 let tabBarImage = UIGraphicsImageRenderer(size: size).image { (_) in
                     let radius = Preferences.shared.avatarStyle.cornerRadiusFraction * 30
                     UIBezierPath(roundedRect: rect, cornerRadius: radius).addClip()
-                    image.draw(in: rect)
+                    maybeGrayscale.draw(in: rect)
                 }
                 let alwaysOriginalImage = tabBarImage.withRenderingMode(.alwaysOriginal)
                 self.tabBarItem.image = alwaysOriginalImage

Tusker/Views/Account Cell/AccountTableViewCell.swift

@@ -63,19 +63,16 @@ class AccountTableViewCell: UITableViewCell {
         let accountID = self.accountID
         
         let avatarURL = account.avatar
-        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-            guard let self = self, let data = data, self.accountID == accountID else { return }
+            guard let self = self else { return }
             self.avatarRequest = nil
             
-            let image: UIImage?
+            guard let image = image,
-            if self.isGrayscale {
+                  self.accountID == accountID,
-                image = ImageGrayscalifier.convert(url: avatarURL, data: data)
+                  let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else { return }
-            } else {
-                image = UIImage(data: data)
-            }
             
             DispatchQueue.main.async {
-                self.avatarImageView.image = image
+                self.avatarImageView.image = transformedImage
             }
         }
         

Tusker/Views/Account Detail/LargeAccountDetailView.swift

@@ -69,11 +69,11 @@ class LargeAccountDetailView: UIView {
         displayNameLabel.updateForAccountDisplayName(account: account)
         usernameLabel.text = "@\(account.acct)"
         
-        avatarRequest = ImageCache.avatars.get(account.avatar) { [weak self] (data) in
+        avatarRequest = ImageCache.avatars.get(account.avatar) { [weak self] (_, image) in
-            guard let self = self, let data = data else { return }
+            guard let self = self, let image = image else { return }
             self.avatarRequest = nil
             DispatchQueue.main.async {
-                self.avatarImageView.image = UIImage(data: data)
+                self.avatarImageView.image = image
             }
         }
     }

Tusker/Views/AccountDisplayNameLabel.swift

@@ -54,9 +54,9 @@ struct AccountDisplayNameLabel<Account: AccountProtocol>: View {
             }
             
             group.enter()
-            let request = ImageCache.emojis.get(emoji.url) { (data) in
+            let request = ImageCache.emojis.get(emoji.url) { (_, image) in
                 defer { group.leave() }
-                guard let data = data, let image = UIImage(data: data) else { return }
+                guard let image = image else { return }
                 
                 let size = CGSize(width: fontSize, height: fontSize)
                 let renderer = UIGraphicsImageRenderer(size: size)

Tusker/Views/Attachments/AttachmentView.swift

@@ -159,7 +159,7 @@ class AttachmentView: UIImageView, GIFAnimatable {
     
     func loadImage() {
         let attachmentURL = attachment.url
-        attachmentRequest = ImageCache.attachments.get(attachmentURL) { [weak self] (data) in
+        attachmentRequest = ImageCache.attachments.get(attachmentURL) { [weak self] (data, _) in
             guard let self = self, let data = data else { return }
             self.attachmentRequest = nil
             if self.attachment.url.pathExtension == "gif" {

Tusker/Views/BaseEmojiLabel.swift

@@ -43,20 +43,13 @@ extension BaseEmojiLabel {
             foundEmojis = true
             
             group.enter()
-            let request = ImageCache.emojis.get(emoji.url) { (data) in
+            let request = ImageCache.emojis.get(emoji.url) { (_, image) in
                 defer { group.leave() }
-                guard let data = data else {
+                guard let image = image,
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: emoji.url, image: image) else {
                     return
                 }
-                let image: UIImage?
+                emojiImages[emoji.shortcode] = transformedImage
-                if Preferences.shared.grayscaleImages {
-                    image = ImageGrayscalifier.convert(url: emoji.url, data: data)
-                } else {
-                    image = UIImage(data: data)
-                }
-                if let image = image {
-                    emojiImages[emoji.shortcode] = image
-                }
             }
             if let request = request {
                 emojiRequests.append(request)

Tusker/Views/ContentTextView.swift

@@ -63,20 +63,13 @@ class ContentTextView: LinkTextView {
         
         for emoji in emojis {
             group.enter()
-            _ = ImageCache.emojis.get(emoji.url) { (data) in
+            _ = ImageCache.emojis.get(emoji.url) { (_, image) in
                 defer { group.leave() }
-                guard let data = data else {
+                guard let image = image,
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: emoji.url, image: image) else {
                     return
                 }
-                let image: UIImage?
+                emojiImages[emoji.shortcode] = transformedImage
-                if Preferences.shared.grayscaleImages {
-                    image = ImageGrayscalifier.convert(url: emoji.url, data: data)
-                } else {
-                    image = UIImage(data: data)
-                }
-                if let image = image {
-                    emojiImages[emoji.shortcode] = image
-                }
             }
         }
         

Tusker/Views/CustomEmojiImageView.swift

@@ -33,16 +33,12 @@ struct CustomEmojiImageView: View {
     }
     
     private func loadImage() {
-        request = ImageCache.emojis.get(emoji.url) { (data) in
+        request = ImageCache.emojis.get(emoji.url) { (_, image) in
-            if let data = data, let image = UIImage(data: data) {
+            DispatchQueue.main.async {
-                DispatchQueue.main.async {
+                self.request = nil
-                    self.request = nil
+                if let image = image {
                     self.image = image
                 }
-            } else {
-                DispatchQueue.main.async {
-                    self.request = nil
-                }
             }
         }
     }

Tusker/Views/Instance Cell/InstanceTableViewCell.swift

@@ -60,8 +60,8 @@ class InstanceTableViewCell: UITableViewCell {
     private func updateThumbnail(url: URL) {
         thumbnailImageView.image = nil
         thumbnailURL = url
-        thumbnailRequest = ImageCache.attachments.get(url) { [weak self] (data) in
+        thumbnailRequest = ImageCache.attachments.get(url) { [weak self] (_, image) in
-            guard let self = self, self.thumbnailURL == url, let data = data, let image = UIImage(data: data) else { return }
+            guard let self = self, self.thumbnailURL == url, let image = image else { return }
             self.thumbnailRequest = nil
             DispatchQueue.main.async {
                 self.thumbnailImageView.image = image

Tusker/Views/Notifications/ActionNotificationGroupTableViewCell.swift

@@ -84,21 +84,20 @@ class ActionNotificationGroupTableViewCell: UITableViewCell {
             imageView.layer.masksToBounds = true
             imageView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadiusFraction * 30
             let avatarURL = account.avatar
-            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-                guard let self = self, let data = data, self.group.id == group.id else { return }
+                guard let self = self else { return }
-                
+                guard let image = image,
-                let image: UIImage?
+                      self.group.id == group.id,
-                if self.isGrayscale {
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else {
-                    image = ImageGrayscalifier.convert(url: avatarURL, data: data)
-                } else {
-                    image = UIImage(data: data)
-                }
-                
-                if let image = image {
                     DispatchQueue.main.async {
                         self.avatarRequests.removeValue(forKey: account.id)
-                        imageView.image = image
                     }
+                    return
+                }
+                
+                DispatchQueue.main.async {
+                    self.avatarRequests.removeValue(forKey: account.id)
+                    imageView.image = transformedImage
                 }
             }
             actionAvatarStackView.addArrangedSubview(imageView)
@@ -133,21 +132,20 @@ class ActionNotificationGroupTableViewCell: UITableViewCell {
             }
             
             let avatarURL = account.avatar
-            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-                guard let self = self, let data = data, self.group.id == groupID else { return }
+                guard let self = self else { return }
-                
+                guard let image = image,
-                let image: UIImage?
+                      self.group.id == groupID,
-                if self.isGrayscale {
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else {
-                    image = ImageGrayscalifier.convert(url: avatarURL, data: data)
-                } else {
-                    image = UIImage(data: data)
-                }
-                
-                if let image = image {
                     DispatchQueue.main.async {
                         self.avatarRequests.removeValue(forKey: account.id)
-                        imageView.image = image
                     }
+                    return
+                }
+                
+                DispatchQueue.main.async {
+                    self.avatarRequests.removeValue(forKey: account.id)
+                    imageView.image = transformedImage
                 }
             }
         }

Tusker/Views/Notifications/FollowNotificationGroupTableViewCell.swift

@@ -65,21 +65,17 @@ class FollowNotificationGroupTableViewCell: UITableViewCell {
             imageView.layer.masksToBounds = true
             imageView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadiusFraction * 30
             let avatarURL = account.avatar
-            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-                guard let self = self, let data = data, self.group.id == group.id else { return }
+                guard let self = self,
-                
+                      let image = image,
-                let image: UIImage?
+                      self.group.id == group.id,
-                if Preferences.shared.grayscaleImages {
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else {
-                    image = ImageGrayscalifier.convert(url: avatarURL, data: data)
+                    return
-                } else {
-                    image = UIImage(data: data)
                 }
                 
-                if let image = image {
+                DispatchQueue.main.async {
-                    DispatchQueue.main.async {
+                    self.avatarRequests.removeValue(forKey: account.id)
-                        self.avatarRequests.removeValue(forKey: account.id)
+                    imageView.image = transformedImage
-                        imageView.image = image
-                    }
                 }
             }
             avatarStackView.addArrangedSubview(imageView)
@@ -103,21 +99,20 @@ class FollowNotificationGroupTableViewCell: UITableViewCell {
             }
             
             let avatarURL = account.avatar
-            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+            avatarRequests[account.id] = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-                guard let self = self, let data = data, self.group.id == groupID else { return }
+                guard let self = self else { return }
-                
+                guard let image = image,
-                let image: UIImage?
+                      self.group.id == groupID,
-                if self.isGrayscale {
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else {
-                    image = ImageGrayscalifier.convert(url: avatarURL, data: data)
-                } else {
-                    image = UIImage(data: data)
-                }
-                
-                if let image = image {
                     DispatchQueue.main.async {
                         self.avatarRequests.removeValue(forKey: account.id)
-                        imageView.image = image
                     }
+                    return
+                }
+                
+                DispatchQueue.main.async {
+                    self.avatarRequests.removeValue(forKey: account.id)
+                    imageView.image = transformedImage
                 }
             }
         }

Tusker/Views/Notifications/FollowRequestNotificationTableViewCell.swift

@@ -68,21 +68,18 @@ class FollowRequestNotificationTableViewCell: UITableViewCell {
             actionLabel.setEmojis(account.emojis, identifier: account.id)
         }
         let avatarURL = account.avatar
-        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-            guard let self = self, self.account == account, let data = data else { return }
+            guard let self = self else { return }
             self.avatarRequest = nil
             
-            let image: UIImage?
+            guard self.account == account,
-            if self.isGrayscale {
+                  let image = image,
-                image = ImageGrayscalifier.convert(url: avatarURL, data: data)
+                  let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else {
-            } else {
+                return
-                image = UIImage(data: data)
             }
             
-            if let image = image {
+            DispatchQueue.main.async {
-                DispatchQueue.main.async {
+                self.avatarImageView.image = transformedImage
-                    self.avatarImageView.image = image
-                }
             }
         }
     }

Tusker/Views/Profile Header/ProfileHeaderView.swift

@@ -191,35 +191,35 @@ class ProfileHeaderView: UIView {
         
         let accountID = account.id
         let avatarURL = account.avatar
-        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-            guard let self = self, let data = data, self.accountID == accountID else { return }
+            guard let self = self, let image = image, self.accountID == accountID else { return }
             self.avatarRequest = nil
             
-            let image: UIImage?
+            let transformedImage: UIImage?
             if self.isGrayscale {
-                image = ImageGrayscalifier.convert(url: avatarURL, data: data)
+                transformedImage = ImageGrayscalifier.convert(url: avatarURL, cgImage: image.cgImage!)
             } else {
-                image = UIImage(data: data)
+                transformedImage = image
             }
             
             DispatchQueue.main.async {
-                self.avatarImageView.image = image
+                self.avatarImageView.image = transformedImage
             }
         }
         if let header = account.header {
-            headerRequest = ImageCache.headers.get(header) { [weak self] (data) in
+            headerRequest = ImageCache.headers.get(header) { [weak self] (_, image) in
-                guard let self = self, let data = data, self.accountID == accountID else { return }
+                guard let self = self, let image = image, self.accountID == accountID else { return }
                 self.headerRequest = nil
                 
-                let image: UIImage?
+                let transformedImage: UIImage?
                 if self.isGrayscale {
-                    image = ImageGrayscalifier.convert(url: header, data: data)
+                    transformedImage = ImageGrayscalifier.convert(url: header, cgImage: image.cgImage!)
                 } else {
-                    image = UIImage(data: data)
+                    transformedImage = image
                 }
                 
                 DispatchQueue.main.async {
-                    self.headerImageView.image = image
+                    self.headerImageView.image = transformedImage
                 }
             }
         }

Tusker/Views/Status/BaseStatusTableViewCell.swift

@@ -260,18 +260,14 @@ class BaseStatusTableViewCell: UITableViewCell {
         
         let avatarURL = account.avatar
         let accountID = account.id
-        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (data) in
+        avatarRequest = ImageCache.avatars.get(avatarURL) { [weak self] (_, image) in
-            guard let self = self, let data = data, self.accountID == accountID else { return }
+            guard let self = self,
-            
+                  let image = image,
-            let image: UIImage?
+                  self.accountID == accountID,
-            if self.isGrayscale {
+                  let transformedImage = ImageGrayscalifier.convertIfNecessary(url: avatarURL, image: image) else { return }
-                image = ImageGrayscalifier.convert(url: avatarURL, data: data)
-            } else {
-                image = UIImage(data: data)
-            }
             
             DispatchQueue.main.async {
-                self.avatarImageView.image = image
+                self.avatarImageView.image = transformedImage
             }
         }
         

Tusker/Views/Status/StatusCardView.swift

@@ -141,18 +141,13 @@ class StatusCardView: UIView {
         if let imageURL = card.image {
             placeholderImageView.isHidden = true
             
-            imageRequest = ImageCache.attachments.get(imageURL, completion: { (data) in
+            imageRequest = ImageCache.attachments.get(imageURL, completion: { (_, image) in
-                guard let data = data else { return }
+                guard let image = image,
-                let image: UIImage?
+                      let transformedImage = ImageGrayscalifier.convertIfNecessary(url: imageURL, image: image) else {
-                if self.isGrayscale {
+                    return
-                    image = ImageGrayscalifier.convert(url: imageURL, data: data)
-                } else {
-                    image = UIImage(data: data)
                 }
-                if let image = image {
+                DispatchQueue.main.async {
-                    DispatchQueue.main.async {
+                    self.imageView.image = transformedImage
-                        self.imageView.image = image
-                    }
                 }
             })
             if imageRequest != nil {