BBMetalCamera can take photo

BBMetalImage/BBMetalImage/BBMetalCamera.swift

@@ -8,6 +8,23 @@
 
 import AVFoundation
 
+/// Camera photo delegate defines handling taking photo result behaviors
+public protocol BBMetalCameraPhotoDelegate: AnyObject {
+    /// Called when camera did take a photo and get Metal texture
+    ///
+    /// - Parameters:
+    ///   - camera: camera to use
+    ///   - texture: Metal texture of the photo
+    func camera(_ camera: BBMetalCamera, didOutput texture: MTLTexture)
+
+    /// Called when camera fail taking a photo
+    ///
+    /// - Parameters:
+    ///   - camera: camera to use
+    ///   - error: error for taking the photo
+    func camera(_ camera: BBMetalCamera, didFail error: Error)
+}
+
 /// Camera capturing image and providing Metal texture
 public class BBMetalCamera: NSObject {
     /// Image consumers
@@ -104,12 +121,54 @@ public class BBMetalCamera: NSObject {
     }
     private var _audioConsumer: BBMetalAudioConsumer?
 
+    private var photoOutput: AVCapturePhotoOutput!
+
+    /// Whether can take photo or not.
+    /// Set this property to true before calling `takePhoto(with:)` method.
+    public var canTakePhoto: Bool {
+        get {
+            lock.wait()
+            let c = _canTakePhoto
+            lock.signal()
+            return c
+        }
+        set {
+            lock.wait()
+            _canTakePhoto = newValue
+            if newValue {
+                if !addPhotoOutput() { _canTakePhoto = false }
+            } else {
+                removePhotoOutput()
+            }
+            lock.signal()
+        }
+    }
+    private var _canTakePhoto: Bool
+
+    /// Camera photo delegate handling taking photo result.
+    /// To take photo, this property should not be nil.
+    public weak var photoDelegate: BBMetalCameraPhotoDelegate? {
+        get {
+            lock.wait()
+            let p = _photoDelegate
+            lock.signal()
+            return p
+        }
+        set {
+            lock.wait()
+            _photoDelegate = newValue
+            lock.signal()
+        }
+    }
+    private weak var _photoDelegate: BBMetalCameraPhotoDelegate?
+
     #if !targetEnvironment(simulator)
     private var textureCache: CVMetalTextureCache!
     #endif
 
     public init?(sessionPreset: AVCaptureSession.Preset = .high, position: AVCaptureDevice.Position = .back) {
         _consumers = []
+        _canTakePhoto = false
         _benchmark = false
         capturedFrameCount = 0
         totalCaptureFrameTime = 0
@@ -213,6 +272,44 @@ public class BBMetalCamera: NSObject {
         }
     }
 
+    @discardableResult
+    private func addPhotoOutput() -> Bool {
+        if photoOutput != nil { return true }
+
+        session.beginConfiguration()
+        defer { session.commitConfiguration() }
+
+        let output = AVCapturePhotoOutput()
+        if !session.canAddOutput(output) {
+            print("Can not add photo output")
+            return false
+        }
+        session.addOutput(output)
+        photoOutput = output
+
+        return true
+    }
+
+    private func removePhotoOutput() {
+        session.beginConfiguration()
+        if let output = photoOutput { session.removeOutput(output) }
+        session.commitConfiguration()
+    }
+
+    /// Takes a photo.
+    /// Before calling this method, set `canTakePhoto` property to true and `photoDelegate` property to nonnull.
+    ///
+    /// - Parameter settings: a specification of the features and settings to use for a single photo capture request
+    public func takePhoto(with settings: AVCapturePhotoSettings? = nil) {
+        lock.wait()
+        if let output = photoOutput,
+            _photoDelegate != nil {
+            let currentSettings = settings ?? AVCapturePhotoSettings(format: [kCVPixelBufferPixelFormatTypeKey as String : kCVPixelFormatType_32BGRA])
+            output.capturePhoto(with: currentSettings, delegate: self)
+        }
+        lock.signal()
+    }
+
     /// Switches camera position (back to front, or front to back)
     ///
     /// - Returns: true if succeed, or false if fail
@@ -369,3 +466,34 @@ extension BBMetalCamera: AVCaptureVideoDataOutputSampleBufferDelegate, AVCapture
         return nil
     }
 }
+
+extension BBMetalCamera: AVCapturePhotoCaptureDelegate {    
+    public func photoOutput(_ output: AVCapturePhotoOutput,
+                            didFinishProcessingPhoto photoSampleBuffer: CMSampleBuffer?,
+                            previewPhoto previewPhotoSampleBuffer: CMSampleBuffer?,
+                            resolvedSettings: AVCaptureResolvedPhotoSettings,
+                            bracketSettings: AVCaptureBracketedStillImageSettings?,
+                            error: Error?) {
+
+        guard let delegate = photoDelegate else { return }
+
+        if let error = error { delegate.camera(self, didFail: error) }
+
+        if let sampleBuffer = photoSampleBuffer,
+            let texture = texture(with: sampleBuffer),
+            let rotatedTexture = rotatedTexture(with: texture, angle: 90) {
+            // Setting `videoOrientation` of `AVCaptureConnection` dose not work. So rotate texture here.
+            delegate.camera(self, didOutput: rotatedTexture)
+        } else {
+            delegate.camera(self, didFail: NSError(domain: "BBMetalCamera.Photo", code: 0, userInfo: [NSLocalizedDescriptionKey : "Can not get Metal texture"]))
+        }
+    }
+
+    private func rotatedTexture(with inTexture: MTLTexture, angle: Float) -> MTLTexture? {
+        let source = BBMetalStaticImageSource(texture: inTexture)
+        let filter = BBMetalRotateFilter(angle: angle, fitSize: true)
+        source.add(consumer: filter).runSynchronously = true
+        source.transmitTexture()
+        return filter.outputTexture
+    }
+}

BBMetalImageDemo/BBMetalImageDemo.xcodeproj/project.pbxproj

@@ -9,6 +9,7 @@
 /* Begin PBXBuildFile section */
 		4A00949F225C53C50089941C /* CameraFilterVC.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A00949E225C53C50089941C /* CameraFilterVC.swift */; };
 		4A084D8D225D9EE30019FB57 /* CameraFilterMenuVC.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A084D8C225D9EE30019FB57 /* CameraFilterMenuVC.swift */; };
+		4A3CAE3F228A060900252B70 /* CameraPhotoFilterVC.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A3CAE3E228A060900252B70 /* CameraPhotoFilterVC.swift */; };
 		4A4CADC2225317C20058BEB6 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A4CADC1225317C20058BEB6 /* AppDelegate.swift */; };
 		4A4CADC4225317C20058BEB6 /* MainMenuVC.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4A4CADC3225317C20058BEB6 /* MainMenuVC.swift */; };
 		4A4CADC7225317C20058BEB6 /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 4A4CADC5225317C20058BEB6 /* Main.storyboard */; };
@@ -46,6 +47,7 @@
 /* Begin PBXFileReference section */
 		4A00949E225C53C50089941C /* CameraFilterVC.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CameraFilterVC.swift; sourceTree = "<group>"; };
 		4A084D8C225D9EE30019FB57 /* CameraFilterMenuVC.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CameraFilterMenuVC.swift; sourceTree = "<group>"; };
+		4A3CAE3E228A060900252B70 /* CameraPhotoFilterVC.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CameraPhotoFilterVC.swift; sourceTree = "<group>"; };
 		4A4CADBE225317C20058BEB6 /* BBMetalImageDemo.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = BBMetalImageDemo.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		4A4CADC1225317C20058BEB6 /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		4A4CADC3225317C20058BEB6 /* MainMenuVC.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MainMenuVC.swift; sourceTree = "<group>"; };
@@ -106,6 +108,7 @@
 				4AFC464E2253CDDC009D37A1 /* StaticImageFilterVC.swift */,
 				4A084D8C225D9EE30019FB57 /* CameraFilterMenuVC.swift */,
 				4A00949E225C53C50089941C /* CameraFilterVC.swift */,
+				4A3CAE3E228A060900252B70 /* CameraPhotoFilterVC.swift */,
 				4A665CFC22721CAA00DFDF4C /* VideoFilterVC.swift */,
 				4A633D672281F33C00138B2A /* VideoFilterVC2.swift */,
 				4A9BCB65227A03E000E02C6F /* VideoPlayerVC.swift */,
@@ -208,6 +211,7 @@
 				4AFC464F2253CDDC009D37A1 /* StaticImageFilterVC.swift in Sources */,
 				4A4CADC2225317C20058BEB6 /* AppDelegate.swift in Sources */,
 				4A00949F225C53C50089941C /* CameraFilterVC.swift in Sources */,
+				4A3CAE3F228A060900252B70 /* CameraPhotoFilterVC.swift in Sources */,
 				4A9BCB66227A03E000E02C6F /* VideoPlayerVC.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

BBMetalImageDemo/BBMetalImageDemo/CameraPhotoFilterVC.swift

@@ -0,0 +1,75 @@
+//
+//  CameraPhotoFilterVC.swift
+//  BBMetalImageDemo
+//
+//  Created by Kaibo Lu on 5/13/19.
+//  Copyright © 2019 Kaibo Lu. All rights reserved.
+//
+
+import UIKit
+import AVFoundation
+import BBMetalImage
+
+class CameraPhotoFilterVC: UIViewController {
+    private var camera: BBMetalCamera!
+    private var metalView: BBMetalView!
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+
+        view.backgroundColor = .gray
+
+        let x: CGFloat = 10
+        let width: CGFloat = view.bounds.width - 20
+        metalView = BBMetalView(frame: CGRect(x: x, y: 100, width: width, height: view.bounds.height - 200),
+                                device: BBMetalDevice.sharedDevice)
+        view.addSubview(metalView)
+
+        let photoButton = UIButton(frame: CGRect(x: x, y: metalView.frame.maxY + 10, width: width, height: 30))
+        photoButton.backgroundColor = .blue
+        photoButton.setTitle("Take photo", for: .normal)
+        photoButton.addTarget(self, action: #selector(clickPhotoButton(_:)), for: .touchUpInside)
+        view.addSubview(photoButton)
+
+        camera = BBMetalCamera(sessionPreset: .hd1920x1080)
+        camera.canTakePhoto = true
+        camera.photoDelegate = self
+        camera.add(consumer: BBMetalLookupFilter(lookupTable: UIImage(named: "test_lookup")!.bb_metalTexture!))
+            .add(consumer: metalView)
+    }
+
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        camera.start()
+    }
+
+    override func viewDidDisappear(_ animated: Bool) {
+        super.viewDidDisappear(animated)
+        camera.stop()
+    }
+
+    @objc private func clickPhotoButton(_ button: UIButton) {
+        camera.takePhoto()
+    }
+}
+
+extension CameraPhotoFilterVC: BBMetalCameraPhotoDelegate {
+    func camera(_ camera: BBMetalCamera, didOutput texture: MTLTexture) {
+        // In main thread
+        let filter = BBMetalLookupFilter(lookupTable: UIImage(named: "test_lookup")!.bb_metalTexture!)
+        let imageView = UIImageView(frame: metalView.frame)
+        imageView.contentMode = .scaleAspectFill
+        imageView.clipsToBounds = true
+        imageView.image = filter.filteredImage(with: texture.bb_image!)
+        view.addSubview(imageView)
+
+        DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
+            imageView.removeFromSuperview()
+        }
+    }
+
+    func camera(_ camera: BBMetalCamera, didFail error: Error) {
+        // In main thread
+        print("Fail taking photo. Error: \(error)")
+    }
+}

BBMetalImageDemo/BBMetalImageDemo/MainMenuVC.swift

@@ -25,6 +25,9 @@ class MainMenuVC: UIViewController {
         let cameraFilter = { [weak self] in
             if let self = self { self.navigationController?.pushViewController(CameraFilterMenuVC(), animated: true) }
         }
+        let cameraPhotoFilter = { [weak self] in
+            if let self = self { self.navigationController?.pushViewController(CameraPhotoFilterVC(), animated: true) }
+        }
         let videoFilter = { [weak self] in
             if let self = self { self.navigationController?.pushViewController(VideoFilterVC(), animated: true) }
         }
@@ -33,6 +36,7 @@ class MainMenuVC: UIViewController {
         }
         list = [("Static image filter", staticImageFilter),
                 ("Camera filter", cameraFilter),
+                ("Camera photo filter", cameraPhotoFilter),
                 ("Video filter", videoFilter),
                 ("Video filter 2", videoFilter2)]