ScreenShot issue in ARKit in swift - swift

i have application that uses ARSCNView. i'm trying to take a screenshot on click of a button and saved that image in the gallery. But when i take a screenshot it does not show the content on that screen. Just show that image, i have some labels on it but it does not show that in an image. This is my code,
#IBAction func captureImage(_ sender: Any) {
image = sceneView.snapshot()
UIImageWriteToSavedPhotosAlbum(image!, nil, nil, nil)
}
How can i show that labels and buttons on ARSCView in a screenshot?

snapshot() will only take screenshot of Scene.
To take screenshot of Scene with Labels and Buttons use below method:
func snapshot(of rect: CGRect? = nil) -> UIImage? {
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, self.view.isOpaque, 0)
self.view.drawHierarchy(in: self.view.bounds, afterScreenUpdates: true)
let fullImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
guard let image = fullImage, let rect = rect else { return fullImage }
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)
}
To Take Screenshot:
#IBAction func takeScreenShotTapped(_ sender: Any) {
let screenShot = snapshot(of: CGRect(x: 80, y: 80, width: 100, height: 100))
}
If you want to take screenshot of fullscreen then just call snapshot().
Hope this will help you :)

Related

How to crop a image 3:4 ? Swift

I tried to look up the answer on the Internet and did not find it, maybe I typed my query wrong on the Internet.
Can you tell me how to crop a 3:4 photo? I can't find the function to crop it. Please share?
You can use this function to crop your image in any AspectRatio (e.g 3:4). You have to pass your Image and desired AspectRatio as a parameter to the function and it will return you the Cropped Image.
func crop(image: UIImage, to aspectRatio: CGFloat) -> UIImage {
let originalAspectRatio = image.size.height/image.size.width
var newImagesize = image.size
if originalAspectRatio > aspectRatio {
newImagesize.height = image.size.width * aspectRatio
} else if originalAspectRatio < aspectRatio {
newImagesize.width = image.size.height / aspectRatio
} else {
return image
}
let center = CGPoint(x: image.size.width/2, y: image.size.height/2)
let origin = CGPoint(x: center.x - newImagesize.width/2, y: center.y - newImagesize.height/2)
let cgCroppedImage = image.cgImage!.cropping(to: CGRect(origin: origin, size: CGSize(width: newImagesize.width, height: newImagesize.height)))!
let croppedImage = UIImage(cgImage: cgCroppedImage, scale: image.scale, orientation: image.imageOrientation)
return croppedImage
}
Usage:
let croppedImage = crop(image: "ImageName", to: 3/4)
Use the following function. For more details read 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
}

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

Why does my photo captured in portrait change to landscape?

I have this cameraView and on top of it I have this UIImageView. The UIImageView is basically a filter that changes the color of the cameraView. I was able to take a picture with the code below and the output image changes the portrait image to landscape. Why does that happen? Thanks!
#IBAction func takePicture(_ sender: Any) {
let settings = AVCapturePhotoSettings(format: [AVVideoCodecKey: AVVideoCodecType.jpeg])
stillImageOutput.capturePhoto(with: settings, delegate: self)
}
func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo:
AVCapturePhoto, error: Error?) {
let renderer = UIGraphicsImageRenderer(size: view.bounds.size)
let image = renderer.image { ctx in
view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
}
if let imageData = photo.fileDataRepresentation() {
if let cameraImage = UIImage(data: imageData) {
let newImage = self.composite(image:cameraImage, overlay: image, scaleOverlay:true)
captureImageView.image = newImage
}
}
}
//combine imageview with uiview
func composite(image:UIImage, overlay:(UIImage), scaleOverlay: Bool = false)->UIImage?{
UIGraphicsBeginImageContext(image.size)
var rect = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)
image.draw(in: rect)
if scaleOverlay == false {
rect = CGRect(x: 0, y: 0, width: overlay.size.width, height: overlay.size.height)
}
overlay.draw(in: rect)
return UIGraphicsGetImageFromCurrentImageContext()
}

Take screenshot of visible area of UIScrollView

I have a UIScrollView as subview of a view controller main view. I'm trying to save a screenshot of whatever is visible in the frame of the UIScrollView only.
UIGraphicsBeginImageContextWithOptions(imageScrollView.bounds.size, false, UIScreen.main.scale)
let context = UIGraphicsGetCurrentContext()
context?.translateBy(x: 0, y: 0)
view.layer.render(in: context!)
let visibleScrollViewImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
let popupImageView = UIImageView(image: visibleScrollViewImage)
popupImageView.layer.borderColor = UIColor.white.cgColor
popupImageView.layer.borderWidth = 4
popupImageView.frame = CGRect(origin: CGPoint(x: 0, y: 400), size: CGSize(width: 400, height: 400))
imageScrollView.removeFromSuperview()
view.addSubview(popupImageView)
The part with the popupImageView is just to test out and see what is actually saving, it seems there is some offset problem, the horizontal axis is fine but i seem to be getting just the top third of the image I want, and above that is just dark space.
Seems like it must be a pretty easy solution but I've searched through all similar questions and can't find an answers.
Thanks heaps!
Try the following. If I do it with a UITableView control, it works.
import UIKit
class ViewController: UIViewController {
#IBAction func snapTapped(_ sender: UIButton) {
UIGraphicsBeginImageContextWithOptions(imageScrollView.bounds.size, true, 1.0)
imageScrollView.drawHierarchy(in: CGRect(origin: CGPoint.zero, size: imageScrollView.bounds.size), afterScreenUpdates: true)
if let image = UIGraphicsGetImageFromCurrentImageContext() {
UIGraphicsEndImageContext()
myImageView.image = image
}
}
}
func screenShotMethod()->UIImage
{
let layer = self.imageScrollView.layer
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(layer.frame.size, false, scale);
layer.render(in: UIGraphicsGetCurrentContext()!)
let screenshot = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return screenshot!
}

How to take a snapshot from UIImage of a UIImageView that is scaleAspectFit mode?

I have an image in a UIImageView:
imageView.contentMode = .scaleAspectFit
imageView.backgroundColor = .red
because of .scaleAspectFit the image view has some red borders and thats OK:
User can added some UIView like label or images over the imageView.
In final step I used the following code to save edited image and user can share it or save it to photo library:
private func generateImage() -> UIImage? {
var finalImage: UIImage?
UIGraphicsBeginImageContextWithOptions(CGSize(width: imageView.frame.size.width, height: imageView.frame.size.height), true, 0)
imageView.drawHierarchy(in: CGRect(x: 0, y: 0, width: imageView.frame.size.width, height: imageView.frame.size.height), afterScreenUpdates: true)
finalImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}
The problem is that the finalImage still has the red borders from imageView.
You can get CGRect of the UIImage displayed in the UIImageView in AspectFit content mode. Please create extension of UIImageView like this,
extension UIImageView {
var contentClippingRect: CGRect {
guard let image = image else { return bounds }
guard contentMode == .scaleAspectFit else { return bounds }
guard image.size.width > 0 && image.size.height > 0 else { return bounds }
let scale: CGFloat
if image.size.width > image.size.height {
scale = bounds.width / image.size.width
} else {
scale = bounds.height / image.size.height
}
let size = CGSize(width: image.size.width * scale, height: image.size.height * scale)
let x = (bounds.width - size.width) / 2.0
let y = (bounds.height - size.height) / 2.0
return CGRect(x: x, y: y, width: size.width, height: size.height)
}
}
You can now use imageView.contentClippingRect to read how read the position and size of the image inside.
You have to do minor changes in your method, call your function with appropriate bounds as contentClippingRect.
Let me know in case of any queries.
UPDATE
Please try this UIImageView+Extension, this might help you. It is in Objective-C code, convert it in Swift.
You can try this as well,
let image = #imageLiteral(resourceName: "Cat03")
let x: CGRect = AVMakeRect(aspectRatio: image.size, insideRect: imageView1.frame)
print(x)
Above code gives you size perfectly.