Swift - Create a GIF from Images and turn it into NSData - ios

This might be an amateur question, but although I have searched Stack Overflow extensibly, I haven't been able to get an answer for my specific problem.
I was successful in creating a GIF file from an array of images by following a Github example:
func createGIF(with images: [NSImage], name: NSURL, loopCount: Int = 0, frameDelay: Double) {
let destinationURL = name
let destinationGIF = CGImageDestinationCreateWithURL(destinationURL, kUTTypeGIF, images.count, nil)!
// This dictionary controls the delay between frames
// If you don't specify this, CGImage will apply a default delay
let properties = [
(kCGImagePropertyGIFDictionary as String): [(kCGImagePropertyGIFDelayTime as String): frameDelay]
]
for img in images {
// Convert an NSImage to CGImage, fitting within the specified rect
let cgImage = img.CGImageForProposedRect(nil, context: nil, hints: nil)!
// Add the frame to the GIF image
CGImageDestinationAddImage(destinationGIF, cgImage, properties)
}
// Write the GIF file to disk
CGImageDestinationFinalize(destinationGIF)
}
Now, I would like to turn the actual GIF into NSData so I can upload it to Firebase, and be able to retrieve it on another device.
To achieve my goal, I have two options: Either to find how to use the code above to extract the GIF created (which seems to directly be created when creating the file), or to use the images on the function's parameters to create a new GIF but keep it on NSData format.
Does anybody have any ideas on how to do this?

Since nobody went ahead for over six months I will just put the answer from #Sachin Vas' comment here:
You can get the data using NSData(contentsOf: URL)

Related

iOS: How to extract thumbnail and metadata from photo file on disk

Apple doc here https://developer.apple.com/documentation/avfoundation/cameras_and_media_capture/capturing_still_and_live_photos/capturing_thumbnail_and_preview_images explains how to capture thubnails.
At the bottom, it says
If you requested an embedded thumbnail image, that image isn't
directly accessible from the AVCapturePhoto object—it's embedded in
the image file data that you get by calling the photo object's
fileDataRepresentation() method.
Seems impossible to separate the embedded thumbnail from the main photo. So what is the meaning of embedded thumbnail?
I want to save the AVCapturePhoto in JPG and raw DNG (requested embedded thumbnails for both) to App's Documents directory (I do not use PhotoKit) and then load it back to a UIImageView.
I save a photo like this:
if let data = capturePhoto.fileDataRepresentation() {
data.write(to: documentsPath, options: [])
}
And load it back to a UIImage like this:
if let data = FileManager.default.contents(at: path) {
let image = UIImage(data: data)
}
But it will be better to load the embedded thubmail first. If a user clicks to see the large image, load the full imgage file then.
I also want to show the metadata, e.g., GPS location, flash status, ISO, shutter speed etc. I wonder how to do that.
AVFoundation's AVAsset wraps some metadata types, but apparently not EXIF data. If you want the thumbnail you have to use the CoreGraphics framework. This function fetches the thumbnail if present, limiting the maximum side length to 512 pixels.
public func getImageThumbnail(url: URL) -> CGImage? {
guard let imageSource = CGImageSourceCreateWithURL(url as CFURL, nil) else { return nil }
let thumbnailOptions: [String: Any] = [
kCGImageSourceCreateThumbnailWithTransform as String: true,
kCGImageSourceCreateThumbnailFromImageIfAbsent as String: false, // true will create if thumbnail not present
kCGImageSourceThumbnailMaxPixelSize as String: 512
]
return CGImageSourceCreateThumbnailAtIndex(imageSource, 0, thumbnailOptions as CFDictionary);
}
For all the rest of the metadata, you can use CGImageSourceCopyPropertiesAtIndex or CGImageSourceCopyMetadataAtIndex.

How to upload an image with Alamofire inside parameters

There's a lot of similar questions on here, but i couldn't find an answer that's help me in solving this problem.
What I want to do is upload an image with Alamofire with parameters
and the image itself should be part of the parameters.
For example the parameters should be like this:
["user_id": 1, "picture": 'and here will be the image that i want to upload']
in the response i will be getting the image as a link like this:
"/uploads/members/'user_id'/images/member_'user_id'/28121284ase2.jpg"
something similar to that.
Also the image should be ' jpg, png and not more than 5MB '.
I'm new to uploading images w\ API so I don't what to do exactly.
I tried every solution I could find in here and google but no luck so far. Any help would be appreciated.
I'm going to assume that you have an instance of UIImage to start with, you'll have to encode it to base64 and send it to your backend as you would any other String parameter. This should help :
extension UIImage {
func toBase64() -> String? {
guard let imageRectoData = jpeg(.low) else {
return nil
}
return imageRectoData.base64EncodedString()
}
enum JPEGQuality: CGFloat {
case lowest = 0
case low = 0.25
case medium = 0.5
case high = 0.75
case highest = 1
}
/// Returns the data for the specified image in JPEG format.
/// If the image object’s underlying image data has been purged, calling this function forces that data to be reloaded into memory.
/// - returns: A data object containing the JPEG data, or nil if there was a problem generating the data. This function may return nil if the image has no data or if the underlying CGImageRef contains data in an unsupported bitmap format.
func jpeg(_ jpegQuality: JPEGQuality) -> Data? {
return jpegData(compressionQuality: jpegQuality.rawValue)
}
}
You can do that by using multipart/form-data request.
your question is relative to this one: Upload image with multipart form-data iOS in Swift

Image Array Causing memory Issue

Currently creating an basic image slideshow application, To do this i have created an UIImage array and calling them with the following code.
let imageNames = (0...50).map
{
"\($0).JPG"
}
let image = UIImage(named: imageNames[0])
imageView.animationImages = image
imageView.animationDuration = 50
imageView.startAnimating()
Was wondering if anyone would be able to offer some advice.
The issue isn't how much memory the image takes on disk, it's about the memory required to address all the pixels on your screen. You don't really need to store the images before you use them. One image of less than 1MB will load very quickly.
Instead you just need to keep a path to the image, and only when you get to the code that displays the image, then you load it, and display it.
So, combining Alexander's and KKRocks on-point answers:
In the top of your class, define your array of filenames:
let imageNames = (0...55).map { "\($0).JPG" }
Where you are displaying your image:
if let image = UIImage(named: images[0]) {
... the code that is blowing up ...
}
If you are not sure how to save a file and retrieve it, please see this answer I recently gave on that subject:
Saving and Retrieving Files in User's Space.
You need to add image name in array instead of UIImage .
let images: [String] = [
"0.JPG",
"1.JPG")!]
Get image from string of array
let image = UIImage(named: images[0])

Load image from the file after rewrite it - UIImage

I have silly problem with loading image from the file. I have two views putted to UITabBarController.
At the first view user can load his image from the Photo Library or Camera. Second view present this photo. This file is on the server. If user doesn't choose his image server sent custom image. If there is uploaded photo it will push user's picture.
When user tap button there is a menu with options. For example we will decide to take picture from the Photo Library. After user took image:
func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage!, editingInfo: [NSObject : AnyObject]!) {
self.saveUserImage(userID, imageData: UIImagePNGRepresentation(image)!)
apiManager.userUploadProfile(userID, imageData: UIImagePNGRepresentation(image)!)
userImageView.image = image
}
func saveUserImage(userUUID: String, imageData: NSData) {
let path = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true).last
let savePath = path! + "/\(userUUID)-user.png"
NSFileManager.defaultManager().createFileAtPath(savePath, contents: imageData, attributes: nil)
}
After that point user can see chosen picture and everything is okey. When user change tab, second view will refresh all data on it and again will download all images and data from the server. Unfortunately images that contains old user image doesn't refresh and there is still old photo.
When we come back to the first tab image is going back to old image but after few seconds.
The strangest thing is if I am checking server there is new uploaded image and in the app container it exist too. When I restart the app everything works perfectly.
It looks like this image is saved in the memory and iOS takes old version from RAM or from some other swap. How refresh UIImageView and show current saved image?
EDIT:
There is a method which load the image
func userProfilePicture(userId: String) -> UIImage {
let cacheDirectory = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true).last
let savePath = cacheDirectory! + "/\(userId)-user.png"
if NSFileManager.defaultManager().fileExistsAtPath(savePath) {
if let image = UIImage(named: savePath) {
return image
}
}
return UIImage(named: "test_avatar")!
}
I can't comment but i was facing a similar issue but i have a question, does the picture get uploaded before the user changes tabs, or after? Even if you call the function to update the database, it takes some time to actually "send the new photo/path to the photo to the database". Here are your options, if the picture is not in the server at the time of the switching tabs, implement a loading ui until it has successfully uploaded and the new, updated value, into the database. An easy way to do that would be to use the SVProgressHUD pod and set the default mask type to .clear which disables user interaction. Option 2, is to pass the actual UIImage via a static variable, or in the prepare for segue method, or through a struct, or any other way and set the picture that needs to be refreshed to the uiimage without getting it from the server only when you switch tabs.
Okey, I found the answer. The problem was in initialize UIImage. We have two methods to load image from file.
First one load the image and cache it in memory. Later it use only a reference to this image data in memory:
let image = UIImage(named: savePath)
Second method load image strictly from file every time when user use that function:
let image = UIImage(contentsOfFile: savePath)
Right now it works perfectly :D

Copy GIF to UIPasteboard

I'm trying to copy a GIF image to the UIPasteboard in swift, at the moment it only copies the static version of the image and seems to convert it to PNG looking at the file extension when I upload it somewhere.
Wondered if anyone had any idea how to achieve this? All other soltions I've found only seem to work when getting NSData from a URL rather than from an image in the bundle
For anyone who ever encounters this problem I managed to find a solution
let url: NSURL = NSBundle.mainBundle().URLForResource("\(self.imageNames[indexPath.row])", withExtension: ".gif")!
let data: NSData = NSData(contentsOfURL: url)!
UIPasteboard.generalPasteboard().setData(data, forPasteboardType: "com.compuserve.gif")
As it turns out you do need to use a URL and extract the NSData of the GIF from that URL.
Here I am getting the URL of the GIF that is in my bundle, searching for it using the name and extension of the image. I am then setting the data in the pasteboard and bingo we have an animated GIF when pasting the result from the pasteboard
It doesn't look like the image property on the pasteboard supports the GIF type.
The associated array of representation types is UIPasteboardTypeListImage, which includes types kUTTypePNG and kUTTypeJPEG.
You could probably do this using the NSData from the GIF though:
import MobileCoreServices
// ...
var image = UIImage(...)
let data = NSData(bytes: &image, length: sizeof(UIImage))
UIPasteboard.generalPasteboard().setData(data, forPasteboardType: kUTTypeGIF as String)) // com.compuserve.gif

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