I'm currently trying to do something fairly simple... just trying to decode then encode an image in Swift 5.
I've been able to see that my image is indeed correct, but it seems like whenever I try to encode the base64 string in Swift, it won't load at all into my UIImageView.
I've run the base64 decoded string in online converters and the image is correctly formatted.
Did I do anything stupid? Thanks so much for any help you can provide!
The Decode Process (currently seems to be working)
let b64 = UIImagePNGRepresentation(tempImage);
var tempImage2 = b64?.base64EncodedString(options: .endLineWithLineFeed);
if (tempImage2 == nil) {
tempImage2 = "";
}
And the encoding process / loading into the image view:
if let data = Data(base64Encoded: tempImage2!, options: .ignoreUnknownCharacters) {
var useImage = UIImage(data: data);
imageView.image = useImage
print("and now the image view should show it??");
}
On printing the decoded base64, everything seems correct. As soon as I run the encoding, however, nothing is being loaded into my UIImageView - just blankness.
Turns out that the above code works for decoding and encoding base64 in Swift. The issue, however, was with respect to what happened after this code.
Turns out I was messing up some things with the imageView, reusing it as a subview and greatly complicating the process.
Thanks for the help, everyone!
Related
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
If this seems like a dupe, sorry. I'm trying to ask a very specific question, and not sure my searching has really led me to the right place. Anyway, here's the setup. Take a picture on the iPhone camera, turn it into base64 string data, shove it up the wire to a Node API, turn that into a file to shove onto S3. Pretty straight forward.
General disclaimers apply; I'd prefer to use a B64 string in JSON for simplicity and universality, and I'll withhold further comments on the silliness of form-encoded uploads :)
Here's my very simple Swift code to produce B64, turn it back into an image, and display it as a proof that the stuff works - at least in Apple land.
Note: "redButton" is one of the assets in my app. I switched to that for the sake of sending much smaller packets at the API for testing, but the results remain. Thanks.
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
// build data packet
imagePicker.dismiss(animated: true, completion: nil)
//let image:UIImage = (info[UIImagePickerControllerOriginalImage] as? UIImage)!
let image:UIImage = UIImage(named: "redButton")!
showAlert( title: "size", msg: String( describing: image.size ) )
let data = UIImageJPEGRepresentation(image, 0.5)
let b64 = data!.base64EncodedData()//.base64EncodedString()//options: Data.Base64EncodingOptions.lineLength64Characters)
let b64String = b64.base64EncodedString()
debugPrint( "len=" + String( describing: b64String.lengthOfBytes(using: String.Encoding.utf8)))
let newDataString = Data.init(base64Encoded: b64String )
let newData = Data.init(base64Encoded: newDataString! )
let newImage = UIImage.init(data: newData!)
tmpImage.image = newImage
}
That all works. I see the image in the little UIImage.
So at least fully in the Apple camp, the img->b64->img works.
However...
When I copy the actual resulting blob of b64-encoded string data, and manually paste it into the source attribute, marked up with the data stuff, it does NOT display the expected image, and in fact, just shows a broken image in the browser.
ie...
<html>
<body>
<img src="data:image/jpg;base64,LzlqLzRBQVFTa1pKUmdBQkFRQUFTQUJJ (brevity)...">
</body>
</html>
So, am I doing something wrong in my proofing in the HTML page? Am I expecting the wrong results from what Apple calls base64 string data? Am I just plain missing something painfully obvious that my sleep-deprived brain is missing?
It eventually gets sent to the server in an HTTP POST call, per normal means, as a dictionary, turned into json via the json encoding stuff in newer Swift.
var params = ["image": [ "content_type": "image/jpg", "filename":"test.jpg", "file_data": b64String] ]
And for the sake of compeleteness, here's the Node code where I reconstitute this data into a binary bit, and from here I shove it up to the S3 system, and in every case, the file is not recognized as a proper JPG file.
var b64 = req.body.image.file_data;
var base64data = new Buffer(b64, 'base64'); // according to all the new-node version docs
I'm on the home stretch of a crunch-time product that we're shoving at investors next week, and apparently this is a critical feature to show off for that meeting.
Tell me I'm missing something painfully obvious, and that I'm stupid. I welcome it, please. It can't not be just something stupid, right?
Thanks!
Here:
let b64 = data!.base64EncodedData()
let b64String = b64.base64EncodedString()
you encode the given data twice. It should be just
let b64String = data!.base64EncodedString()
Your “in Apple land” test works because
let newDataString = Data.init(base64Encoded: b64String )
let newData = Data.init(base64Encoded: newDataString! )
also decodes the Base64 twice. That would now be just
let newData = Data(base64Encoded: b64String)
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)
I'm working with AEXML to write and read xml documents in Swift. I have the writing working no problem. And I have everything setup for the reading, but I can't seem to turn the saved text xml into the document object. It only ever gets the first element and none of the children. I've tried removing all the lines and spaces but still nothing. The content is reading into the String just fine and I've tried converting the data back to a string and it isn't getting messed up in conversion. Is this even possible with AEXML or am I just doing it wrong?
let doc = AEXMLDocument()
let content = try String(contentsOf:NSURL(string:file) as! URL)
let data = content.data(using: String.Encoding(rawValue: String.Encoding.utf8.rawValue))!
let xml = NSString(data:data, encoding:String.Encoding.utf8.rawValue)
try doc.loadXMLData(data)
So I figured out that I was actually using an outdated version of AEXML which clearly wasn't working anymore. The updated code looks like this.
let content = try String(contentsOf:NSURL(string:file) as! URL)
let data = content.data(using: String.Encoding(rawValue: String.Encoding.utf8.rawValue))!
let options = AEXMLOptions()
let doc = try AEXMLDocument(xml:data,options:options)
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