Swift 4 ImageScrollView resizing visible cells in UITableView - swift

I am using the ImageScrollView cocoa pod v1.5 inside a UITableViewCell (Swift 4).
I am downloading images from Firestore using SDWebImage (but also tried Kingfisher with no change in my issue). My images are 700x700 and are being displayed in a ImageScrollView that, depending upon device, is about 400x100. I have set the SDWebImage imageContentMode to .widthFill. I rotate the image to get it in the form I want for the tableview. I use it in it's regular orientation in other places.
The first time my cells are shown the images are shown correctly. If I go back to the previous page, then show the same results in the table again, the visible cells will have their images no longer fitting correctly with regards to width, they are now too wide. If I scroll down hiding those cells all new cells are properly displayed, when I scroll back up the incorrect cells are now displaying correctly. Happens in simulator and actual phone.
Here are the important parts of my UITableViewCell class :
class MyTableCell: UITableViewCell {
var ski : Ski!
var skiImageView: UIImageView = UIImageView()
#IBOutlet weak var skiImageScrollView: ImageScrollView!
func configureCell(ski: Ski) {
self.ski = ski
let imageUrl = ski.imageUrl!
let url = URL(string: imageUrl)
skiImageView.sd_setImage(with: url, placeholderImage: placeholderImage, options: [.retryFailed, .continueInBackground]
, completed: {
(image, error, cacheType, url) in
if (error != nil) {
print("ConfigureCell Error : \(error!)")
return;
}
let rotatedImage = self.imageRotatedByDegrees(oldImage: image!, deg: 90.0)
self.skiImageScrollView.display(image: rotatedImage) var image = self.skiImageView.image!
self.skiImageScrollView.imageContentMode = .widthFill
})
}
func imageRotatedByDegrees(oldImage: UIImage, deg degrees: CGFloat) -> UIImage {
//Calculate the size of the rotated view's containing box for our drawing space
let rotatedViewBox: UIView = UIView(frame: CGRect(x: 0, y: 0, width: oldImage.size.width, height: oldImage.size.height))
let t: CGAffineTransform = CGAffineTransform(rotationAngle: degrees * CGFloat.pi / 180)
rotatedViewBox.transform = t
let rotatedSize: CGSize = rotatedViewBox.frame.size
//Create the bitmap context
UIGraphicsBeginImageContext(rotatedSize)
let bitmap: CGContext = UIGraphicsGetCurrentContext()!
//Move the origin to the middle of the image so we will rotate and scale around the center.
bitmap.translateBy(x: rotatedSize.width / 2, y: rotatedSize.height / 2)
//Rotate the image context
bitmap.rotate(by: (degrees * CGFloat.pi / 180))
//Now, draw the rotated/scaled image into the context
bitmap.scaleBy(x: 1.0, y: -1.0)
bitmap.draw(oldImage.cgImage!, in: CGRect(x: -oldImage.size.width / 2, y: -oldImage.size.height / 2, width: oldImage.size.width, height: oldImage.size.height))
let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return newImage
}
Another strange thing is if I slap the back of my phone or drop it on my desk, the images will jump down so only parts of the top of my image are visible in the ImageScrollView, but callbacks from ImageScrollView for zooming are not activated, so no idea what is happening there either.

You might try the following:
imageScrollView.imageContentMode = .aspectFit
before
self.skiImageScrollView.display(image: rotatedImage)

Related

How can I use CGRect() dynamically?

I have the following scene example where I can crop an image based on the selection (red square).
That square has dynamic Height and Width - base on this fact I want to use the selected Height and Width to crop what is inside of the Red square.
The function that I am using for cropping is from Apple developer and looks like this:
func cropImage(_ inputImage: UIImage, toRect cropRect: CGRect, viewWidth: CGFloat, viewHeight: CGFloat) -> UIImage?
{
let imageViewScale = max(inputImage.size.width / viewWidth,
inputImage.size.height / viewHeight)
// Scale cropRect to handle images larger than shown-on-screen size
let cropZone = CGRect(x:cropRect.origin.x * imageViewScale,
y:cropRect.origin.y * imageViewScale,
width:cropRect.size.width * imageViewScale,
height:cropRect.size.height * imageViewScale)
// Perform cropping in Core Graphics
guard let cutImageRef: CGImage = inputImage.cgImage?.cropping(to:cropZone)
else {
return nil
}
// Return image to UIImage
let croppedImage: UIImage = UIImage(cgImage: cutImageRef)
return croppedImage
}
Now. I want to use the given Height and Width to crop that selection.
let croppedImage = cropImage(image!, toRect: CGRect(x:?? , y:?? , width: ??, height: ??), viewWidth: ??, viewHeight: ??)
What should I fill in these parameters in order to crop the image based on the above dynamic selection?
Ok, since you just have info of width and height of the cropping shape. You'll need to calculate the x and y by yourself.
First, let's consider these information:
// let's pretend this is a sample of size that your crop tool provides to you
let cropSize = CGSize(width: 120, height: 260)
Next, you'll need to obtain the display size (width and height) of your image. Display size here is the frame's size of your image, not the size of the image itself.
// again, lets pretend it's just a frame size of your image
let imageSize = CGSize(width: 320, height: 480)
With this info, you can obtain the x and y necessary to compose a CGRect and then, provide to a cropping function you desire.
let x = (imageSize.width - cropSize.width) / 2
let y = (imageSize.height - cropSize.height) / 2
So now, you can create a rectangle to crop your image like this:
let cropRect = CGRect(x: x, y: y, width: cropSize.width, height: cropSize.height)
With cropRect you can use on both cropping or cropImage functions mentioned in your question.
Ok, let's assume that your image is in imageView, wich is located somewhere in your screen. The rect is a variable where your selected frame (related to the imageView.frame) is stored. So the result is:
let croppedImage = cropImage(image!, toRect: rect, viewWidth: imageView.width, viewHeight: imageView.height)
I've used the info from all of your answers and especially #matt's comment and this is the final solution.
Using the input values that my red square returned, I've adapted the original Crop function to this one:
func cropImage(_ inputImage: UIImage, width: Double, height: Double) -> UIImage?
{
let imsize = inputImage.size
let ivsize = UIScreen.main.bounds.size
var scale : CGFloat = ivsize.width / imsize.width
if imsize.height * scale < ivsize.height {
scale = ivsize.height / imsize.height
}
let croppedImsize = CGSize(width:height/scale, height:width/scale)
let croppedImrect =
CGRect(origin: CGPoint(x: (imsize.width-croppedImsize.width)/2.0,
y: (imsize.height-croppedImsize.height)/2.4),
size: croppedImsize)
let r = UIGraphicsImageRenderer(size:croppedImsize)
let croppedIm = r.image { _ in
inputImage.draw(at: CGPoint(x:-croppedImrect.origin.x, y:-croppedImrect.origin.y))
}
return croppedIm
}

Cropping CGRect from AVCapturePhotoOutput (resizeAspectFill)

I have found the following problem and unfortunatly other posts have not helped me to a working solution.
I have a simple app that shows the camera preview (AVCaptureVideoPreviewLayer) where the video gravity has been set to resizeAspectFill (videoGravity = .resizeAspectFill).
From my understanding this only streches the image in the width to make to fill the screen.
On my preview layer I also have applied a CGRect as a mask with fixed x, y, width and height.
Now once I take a photo i'm trying to crop that exact rectangle out of the image. For my understanding i'm supposed to use some kind of math to convert the CGRect to the same aspect ratio as the image that I get from the AVCapturePhotoOutput method but it never seems to crop correctly in the width.
private func cropImage(image: UIImage) {
let rect = CGRect(x: 25, y: 150, width: 325, height: 230)
let scale = CGAffineTransform(scaleX: 1/self.view.frame.width, y: 1/self.view.frame.height)
let flip = CGAffineTransform(scaleX: 1, y: -1).translatedBy(x: 0, y: -1)
let bounds = rect.applying(scale).applying(flip)
let topLeft = bounds.topLeft.scaled(to: image.size)
let topRight = bounds.topRight.scaled(to: image.size)
let bottomLeft = bounds.bottomLeft.scaled(to: image.size)
let bottomRight = bounds.bottomRight.scaled(to: image.size)
var ciImage = CIImage(image: image.forceSameOrientation())!
ciImage = ciImage.applyingFilter("CIPerspectiveCorrection", parameters: [
"inputTopLeft": CIVector(cgPoint: bottomLeft),
"inputTopRight": CIVector(cgPoint: bottomRight),
"inputBottomLeft": CIVector(cgPoint: topLeft),
"inputBottomRight": CIVector(cgPoint: topRight)
])
let context = CIContext()
let cgImage = context.createCGImage(ciImage, from: ciImage.extent)
let output = UIImage(cgImage: cgImage!)
let vc = PreviewViewController()
vc.imageView.image = output
self.present(vc, animated: true, completion: nil)
}
So again, basically it does crop at the correct height but its only the width that does not seem to go well.
Image example of what I would want to capture.
https://imgur.com/a/8GryEgX
As you can see the bounding box in the top left stops after the "Q" button.
Result:
https://imgur.com/FwKRWxK
As you can see in this image, it does crop correctly in the height however if we take a look at the top left it also includes half of the button to the left of the "Q" (Tab button)
Any help towards the solution would be appreciated!
I managed to solve the issue with this code.
private func cropToPreviewLayer(from originalImage: UIImage, toSizeOf rect: CGRect) -> UIImage? {
guard let cgImage = originalImage.cgImage else { return nil }
// This previewLayer is the AVCaptureVideoPreviewLayer which the resizeAspectFill and videoOrientation portrait has been set.
let outputRect = previewLayer.metadataOutputRectConverted(fromLayerRect: rect)
let width = CGFloat(cgImage.width)
let height = CGFloat(cgImage.height)
let cropRect = CGRect(x: (outputRect.origin.x * width), y: (outputRect.origin.y * height), width: (outputRect.size.width * width), height: (outputRect.size.height * height))
if let croppedCGImage = cgImage.cropping(to: cropRect) {
return UIImage(cgImage: croppedCGImage, scale: 1.0, orientation: originalImage.imageOrientation)
}
return nil
}
usage of the piece of code for my case:
let rect = CGRect(x: 25, y: 150, width: 325, height: 230)
let croppedImage = self.cropToPreviewLayer(from: image, toSizeOf: rect)
self.imageView.image = croppedImage

Swift ImageCropper returns an image outside of the specified "window"

I am making an app that has a UIWebView along with a button on a single view controller. When the button is clicked, an image (of the UIWebView) is captured using UIGraphicsContext.
This part works great! But when the button is clicked, after capturing the image, it displays the image as a subview on the same view, and I have been trying to use an ImageCropper Library that draws a CGRect in another subview over the UIImageView on the screen with a submit button. The rectangle itself can be resized (dragging the corners/edges) and moved around the view.
When the submit button is clicked, another subview is displayed in the top left hand portion of screen and display the image that was cropped (after clicking submit button) The idea is to only capture what is inside the rectangle. I am able to get the code working but the image captured is of the same image but not a section that is inside the CGRect.
I have 3 images that show how it works and shows the image that is cropped incorrectly.enter image description here . Shot 1 . Shot 2
Shot 3. I believe my problems lies within the size of image captured and the size of the image with the crop rect are not equal and that is why it is distorting it.
Does anyone know what might be the cause? Sorry for the long winded question but any help would be greatly appreciated!
Here is my code below:
ViewController.swift:
class ViewController: UIViewController {
#IBOutlet var webView: UIWebView!
#IBOutlet var imageView: UIImageView!
override func viewDidLoad() {
imageView.isHidden = true
let aString = URL(string: "https://www.kshuntfishcamp.com/home.page")
webView.loadRequest(URLRequest(url: aString!))
super.viewDidLoad()
}
#IBAction func takePhotoPressed(_ sender: UIButton) {
UIGraphicsBeginImageContextWithOptions(webView.bounds.size, false, 0.0)
if let aContext = UIGraphicsGetCurrentContext(){
webView.layer.render(in: aContext)
}
let capturedImage:UIImage? = UIGraphicsGetImageFromCurrentImageContext()
imageView = UIImageView(frame: CGRect(x: 22, y: 123, width: 330, height: 330))
let image = capturedImage
imageView.image = image
imageView.contentMode = UIViewContentMode.scaleAspectFill
imageView.clipsToBounds = true
imageView.isHidden = true
webView.isHidden = true
let editView = EditImageView(frame: self.view.frame)
let image2 = capturedImage!
editView.initWithImage(image: image2)
let croppedImage = editView.getCroppedImage()
self.view.addSubview(editView)
self.view.backgroundColor = UIColor.clear
UIImageWriteToSavedPhotosAlbum(croppedImage, nil, nil, nil)
}
EditImageView.swift - source (https://github.com/Thanatos-L/LyEditImageView)-only including parts that seem relevant to solving the problem
func initWithImage(image:UIImage){
imageView = UIImageView(frame: CGRect(x: 22, y: 123, width: 330, height: 330))
imageView.tag = IMAGE_VIEW_TAG;
self.addSubview(self.imageView)
imageView.isUserInteractionEnabled = true;
imageView.image = image
imageView.frame = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)
let frame = AVMakeRect(aspectRatio: imageView.frame.size, insideRect: self.frame);
imageView.frame = frame
originImageViewFrame = frame
NSLog("initWithImage %#", NSStringFromCGRect(originImageViewFrame))
imageZoomScale = 1.0
commitInit()
}
private func cropImage() {
let rect = self.convert(cropView.frame, to: imageView)
let imageSize = imageView.image?.size
let ratio = originImageViewFrame.size.width / (imageSize?.width)!
let zoomedRect = CGRect(x: rect.origin.x / ratio, y: rect.origin.y / ratio, width: rect.size.width / ratio, height: rect.size.height / ratio)
let croppedImage = cropImage(image: imageView.image!, toRect: zoomedRect)
var view: UIImageView? = self.viewWithTag(1301) as? UIImageView
if view == nil {
view = UIImageView()
}
view?.frame = CGRect(x: 0, y: 0, width: croppedImage.size.width , height: croppedImage.size.height)
view?.image = croppedImage
view?.tag = 1301
self.addSubview(view!)
}

WKWebView Swift - Make screenshot of website without the fixed menu bar

I'm using Xcode Swift 3 and WKWebView to display the websites. Then I try to screen capture the website using the following code that I've found from the Internet. There are some websites that come with a fixed menu bar either at the top or bottom of the website. Hence, as I scroll the website, the menu bar does not move with the browser and is fixed on the screen. The problem is this fixed menu bar of the website appears on my screenshot. Is there a way to make a screenshot without the fixed menu bar? Thanks in advance for your help.
func snapshot(of rect: CGRect? = nil) -> UIImage? {
// snapshot entire view
UIGraphicsBeginImageContextWithOptions(bounds.size, isOpaque, 0)
drawHierarchy(in: bounds, afterScreenUpdates: true)
let wholeImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
// if no `rect` provided, return image of whole view
guard let image = wholeImage, let rect = rect else { return wholeImage }
// otherwise, grab specified `rect` of image
let scale = image.scale
let scaledRect = CGRect(x: rect.origin.x * scale, y: rect.origin.y * scale, width: rect.size.width * scale, height: rect.size.height * scale)
guard let cgImage = image.cgImage?.cropping(to: scaledRect) else { return nil }
return UIImage(cgImage: cgImage, scale: scale, orientation: .up)
}

Cropping an image from the top in Swift

I am trying to crop this image, which is a SKSpriteNode:
I am trying to crop this image from the top, so that I maintain the bottom semi circle of this shape. For instance, it'd be cropped to this:
So I use these two methods to accomplish this task:
func recalculateScore() {
currentScore -= decreaseRate
let image = UIImage(cgImage: (vial.texture?.cgImage())!)
vial.texture = SKTexture(image: cropBottomImage(image: image))
}
func cropBottomImage(image: UIImage) -> UIImage {
let height = CGFloat(image.size.height / 3)
let rect = CGRect(x: 0, y: image.size.height - height, width: image.size.width, height: height)
return cropImage(image: image, toRect: rect)
}
func cropImage(image:UIImage, toRect rect:CGRect) -> UIImage {
let imageRef:CGImage = image.cgImage!.cropping(to: rect)!
let croppedImage:UIImage = UIImage(cgImage:imageRef)
return croppedImage
}
However, this leads to this result:
It is as if it was being compressed. I think my issue might be in this line:
let rect = CGRect(x: 0, y: image.size.height - height, width: image.size.width, height: height)
Does the CGRect coordinate of (0,0) lie within the top most left corner? I am a bit confused on what the x and y parameters for the CGRect mean?
Resize your sprite, what is happening is the cropped texture is stretching to fill the sprite, and since you only crop vertically, it will only stretch vertically
func recalculateScore() {
currentScore -= decreaseRate
let image = UIImage(cgImage: (vial.texture?.cgImage())!)
vial.texture = SKTexture(image: cropBottomImage(image: image))
vial.size = vial.texture.size
}