Question

我有一个类可以获取所有用户资源，获取图像，然后对每个图像执行面部检测。我从viewDidLoad函数调用我的类，如下所示：

   override func viewDidLoad() {

    _ = autoreleasepool{

        return faceProcessing()    
    }
  }

这是班级：

class faceProcessing{

let manager = PHImageManager.default()
let option = PHImageRequestOptions()

init() {
    let realm = try! Realm()
    let assets = getAssets(realm: realm)

    option.isSynchronous = true
    option.deliveryMode = .fastFormat
    option.isNetworkAccessAllowed = true

    var featuresCount = 0

    for assetIndex in 0...assets.count-1{


        featuresCount += autoreleasepool{() -> Int? in
            print(assetIndex)
            var facesCount = 0
           faceDetection(asset: assets[assetIndex]) { (features) in
                facesCount = features
            }

            return facesCount
        }!
    }

    print(featuresCount)    
}

func getAssets(realm: Realm)->[PHAsset]{

    return autoreleasepool{ () -> [PHAsset] in
    let images = realm.objects(Image.self).filter("asset != nil")
    let ids: [String] = images.map {$0.id}
    let options = PHFetchOptions()
    options.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: true)]
    let assets = PHAsset.fetchAssets(withLocalIdentifiers: ids, options: options)
    var assetArray = [PHAsset]()

    if(assets.count > 1){
            for assetIndex in 0...assets.count-1{
            assetArray.append(assets[assetIndex])
        }
    }
    return assetArray
    }
}

func faceDetection(asset: PHAsset, completionHandler:@escaping (Int)->Void){    
  manager.requestImageData(for: asset, options: option){
        (data, responseString, imageOriet, info) in
        if (data != nil){
           weak var faceDetector = CIDetector(ofType: CIDetectorTypeFace, context: nil, options: [CIDetectorAccuracy: CIDetectorAccuracyHigh])

            let faces = (faceDetector?.features(in: CIImage(data: data!)!))
            faceDetector = nil
            completionHandler((faces?.count)!)
        }else{
            print(info)
        }

    }
}
}

问题是在完成获取图像和检测面部的过程后，内存将不会释放。在此过程之前，内存大约为60MB，在此过程中，内存大小在400MB到500MB之间，当过程完成时，内存大约为300MB。是否有一种方法可以释放整个内存，并在完成该过程后有60MB？

以下是仪器的外观：

看起来人脸检测没有释放内存，所以有一种方法可以从内存中释放CIDetection吗？

Swift内存不会释放

0 个答案: