Tesseract in iOS (Swift) - How to Separate Text and Numbers in UITextField? - ios

I have a Swift-based application that currently implements the Tesseract OCR framework (similar to the form in this tutorial: http://www.raywenderlich.com/93276/implementing-tesseract-ocr-ios). So upon taking a picture and employing Tesseract, I obtain the following output in a UITextField object:
Subtotal 155.60
Tax 14.02
Total 169.82
So now I would like to separate the text from the numbers in the UITextField. I was considering using the "contain" function built into Swift on a matrix containing all values in price format ([0.01 0.02, etc.]) but this will only return a boolean as outlined in this post (How to have a textfield scan for all values in an array individually in swift?). Does anyone have any suggestions on how to do this? Cheers!
Tesseract Implementation
func performImageRecognition(image: UIImage)
// 0
// 1
let tesseract = G8Tesseract()
// 2
tesseract.language = "eng"
// 3
tesseract.engineMode = .TesseractCubeCombined
// 4
tesseract.pageSegmentationMode = .Auto
// 5
tesseract.maximumRecognitionTime = 60.0
// 6
tesseract.image = image.g8_blackAndWhite()
tesseract.recognize()
// 7
textView.text = tesseract.recognizedText
textView.editable = true

Sounds like you might want to look into using Regular Expressions
func seperate (text: String) -> (text: String?, value: String?) {
// You might want to do an extra check here to ensure the whole string is valid
// i.e., nothing in between the two parts of the string
let textMatch = text.rangeOfString("^([A-Z]|[a-z])+", options: .RegularExpressionSearch)
let priceMatch = text.rangeOfString("[0-9]*.[0-9]{2}$", options: .RegularExpressionSearch)
// You might want to adjust regex to handle price edge cases, such as 15 (rather than 15.00) etc
if let textMatch = textMatch, priceMatch = priceMatch {
let textValue = text.substringWithRange(textMatch)
let priceValue = text.substringWithRange(priceMatch)
return(textValue, priceValue)
} else {
return (nil, nil)
}
}
seperate("Subtotal 155.60") // -> Subtotal, 155.60

Related

iOS fast image difference comparison

Im looking for a fast way to compare two frames of video, and decide if a lot has changed between them. This will be used to decide if I should send a request to image recognition service over REST, so I don't want to keep sending them, until there might be some different results. Something similar is doing Vuforia SDK. Im starting with a Framebuffer from ARKit, and I have it scaled to 640:480 and converted to RGB888 vBuffer_image. It could compare just few points, but it needs to find out if difference is significant nicely.
I started by calculating difference between few points using vDSP functions, but this has a disadvantage - if I move camera even very slightly to left/right, then the same points have different portions of image, and the calculated difference is high, even if nothing really changed much.
I was thinking about using histograms, but I didn't test this approach yet.
What would be the best solution for this? It needs to be fast, it can compare just smaller version of image, etc.
I have tested another approach using VNFeaturePointObservation from Vision. This works a lot better, but Im afraid it might be more CPU demanding. I need to test this on some older devices. Anyway, this is a part of code that works nicely. If someone could suggest some better approach to test, please let know:
private var lastScanningImageFingerprint: VNFeaturePrintObservation?
// Returns true if these are different enough
private func compareScanningImages(current: VNFeaturePrintObservation, last: VNFeaturePrintObservation?) -> Bool {
guard let last = last else { return true }
var distance = Float(0)
try! last.computeDistance(&distance, to: current)
print(distance)
return distance > 10
}
// After scanning is done, subclass should prepare suggestedTargets array.
private func performScanningIfNeeded(_ sender: Timer) {
guard !scanningInProgress else { return } // Wait for previous scanning to finish
guard let vImageBuffer = deletate?.currentFrameScalledImage else { return }
guard let image = CGImage.create(from: vImageBuffer) else { return }
func featureprintObservationForImage(image: CGImage) -> VNFeaturePrintObservation? {
let requestHandler = VNImageRequestHandler(cgImage: image, options: [:])
let request = VNGenerateImageFeaturePrintRequest()
do {
try requestHandler.perform([request])
return request.results?.first as? VNFeaturePrintObservation
} catch {
print("Vision error: \(error)")
return nil
}
}
guard let imageFingerprint = featureprintObservationForImage(image: image) else { return }
guard compareScanningImages(current: imageFingerprint, last: lastScanningImageFingerprint) else { return }
print("SCANN \(Date())")
lastScanningImageFingerprint = featureprintObservationForImage(image: image)
executeScanning(on: image) { [weak self] in
self?.scanningInProgress = false
}
}
Tested on older iPhone - as expected this causes some frame drops on camera preview. So I need a faster algorithm

IOS/Swift/AVSpeechSynthesizer: Control Speed of Enqueued Utterances

In order to exert greater control over speech in the spirit of this tutorial for an audiobook although I'm not following it exactly, I have tried sending smaller pieces of a string such as phrases in separate chunks. The speech synthesizer enqueues each utterance and speaks them one after the other. In theory, this is supposed to give you greater control to make speech sound less robotic.
I can get the synthesizer to speak the chunks in order however there is a long delay between each so it sounds way worse than just sending all the text at the same time.
Is there anyway to speed up the queue so that the utterances are spoken one after the other with no delay?
Setting the properties: utt.preUtteranceDelay and utt.postUtteranceDelay to zero seconds does not seem to have any effect
Here is my code:
phraseCounter = 0
func readParagraph(test: String) {
let phrases = test.components(separatedBy: " ")
for phrase in phrases {
phraseCounter = phraseCounter+1
let utt = AVSpeechUtterance(string:phrase)
let preUtteranceDelayInSecond = 0
let postUtteranceDelayInSecond = 0
utt.preUtteranceDelay = TimeInterval.init(exactly:preUtteranceDelayInSecond)!
utt.postUtteranceDelay = TimeInterval.init(exactly:postUtteranceDelayInSecond)!
voice.delegate = self
if (phraseCounter == 2) {
utt.rate = .8
}
voice.speak(utt)
}
}
Is there anyway to speed up the queue so that the utterances are spoken one after the other with no delay?
As you did, the only way is to set the post and pre UtteranceDelay properties to 0 which is the default value by the way.
As recommended here, I implemented the code snippet hereafter (Xcode 10, Swift 5.0 and iOS 12.3.1) to check the impact of different UtteranceDelay values ⟹ 0 is the best solution to improve the speed of enqueued utterances.
var synthesizer = AVSpeechSynthesizer()
var playQueue = [AVSpeechUtterance]()
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
for i in 1...10 {
let stringNb = "Sentence number " + String(i) + " of the speech synthesizer."
let utterance = AVSpeechUtterance(string: stringNb)
utterance.rate = AVSpeechUtteranceDefaultSpeechRate
utterance.pitchMultiplier = 1.0
utterance.volume = 1.0
utterance.postUtteranceDelay = 0.0
utterance.preUtteranceDelay = 0.0
playQueue.append(utterance)
}
synthesizer.delegate = self
for utterance in playQueue {
synthesizer.speak(utterance)
}
}
If a delay is too important with the '0' value in your code, the incoming string is maybe the problem? (adapt the code snippet above to your needs)

How to get specific information of image using Firebase-CloudVision(ML)

I am using Firebase cloudVision (ML) API to read image.
I am able to the get the information of an image back but it is not specific.
Example: when I take and upload a picture of MacBook it is giving the output as "notebook,Loptop,electronic device..etc".
But I want to get its brand name like Apple MacBook ,
I have seen few apps doing this .
I could not find any information regarding this, so here I am posting.
Please suggest or guide if anyone come across this
My Code:
func pickedImage(image: UIImage) {
imageView.image = image
imageView.contentMode = .scaleAspectFit
guard let image = imageView.image else { return }
// let onCloudLabeler =
Vision.vision().cloudImageLabeler(options: options)
let onCloudLabeler = Vision.vision().cloudImageLabeler()
// Define the metadata for the image.
let imageMetadata = VisionImageMetadata()
imageMetadata.orientation = .topLeft
// Initialize a VisionImage object with the given UIImage.
let visionImage = VisionImage(image: image)
visionImage.metadata = imageMetadata
onCloudLabeler.process(visionImage) { labels, error in
guard error == nil, let labels = labels, !labels.isEmpty
else {
// [START_EXCLUDE]
let errorString = error?.localizedDescription ?? "No results returned."
print("Label detection failed with error: \(errorString)")
//self.showResults()
// [END_EXCLUDE]
return
}
// [START_EXCLUDE]
var results = [String]()
let resultsText = labels.map { label -> String in
results.append(label.text)
return "Label: \(label.text), " +
"Confidence: \(label.confidence ?? 0), " +
"EntityID: \(label.entityID ?? "")"
}.joined(separator: "\n")
//self.showResults()
// [END_EXCLUDE]
print(results.count)
print(resultsText)
self.labelTxt.text = results.joined(separator: ",")
results.removeAll()
}
}
If you've seen other apps doing something that your app doesn't do, those other apps are likely using a different ML model than the one you're using.
If you want to accomplish the same using ML Kit for Firebase, you can use a custom model that you either trained yourself or got from another source.
As Puf said, the apps you saw are probably using their own custom ML model. ML Kit now supports creating custom image classification models from your own training data. Check out the AutoML Vision Edge functionality here: https://firebase.google.com/docs/ml-kit/automl-vision-edge

Getting Climacons to display in UILabel with CZWeatherKit in Swift

So I am using the CZWeatherKit library to grab weather data from forecast.io.
When I get results, it sends a climacon UInt8 char, which should match to an icon if the climacon font is installed. I did that but it only shows the char, not the actual icon. Here is the code, it prints a quote i.e. " which is the correct mapping to ClimaconCloudSun, but the icon doesn't show. I followed these instructions to install the climacons.ttf font
request.sendWithCompletion { (data, error) -> Void in
if let error = error {
print(error)
} else if let weather = data {
let forecast = weather.dailyForecasts.first as! CZWeatherForecastCondition
dispatch_async(dispatch_get_main_queue(), { () -> Void in
// I get back good results, this part works
let avgTempFloat = (forecast.highTemperature.f + forecast.lowTemperature.f) / 2
let avgTemp = NSDecimalNumber(float: avgTempFloat).decimalNumberByRoundingAccordingToBehavior(rounder)
self.temperatureLabel.text = String(avgTemp)
self.weatherLabel.text = forecast.summary
// this part does not work, it has the right char, but does not display icon
// I tried setting self.climaconLabel.font = UIFont(name: "Climacons-Font", size: 30) both in IB and programmatically
let climaChar = forecast.climacon.rawValue
let climaString = NSString(format: "%c", climaChar)
self.climaconLabel.text = String(climaString)
})
}
}
I solved the exact same issue, the problem was the font file. Replace your current font with the one provided here: https://github.com/comyar/Sol/blob/master/Sol/Sol/Resources/Fonts/Climacons.ttf
You've probably moved on from this problem by now, but I'll leave this here for future use.
You need to call setNeedsLayout on the label after you change the title text to the desired value, and the label will change to the corresponding icon.

How can I prevent iOS from automatically underlining numbers in Swift?

I'm building a side project to play around with iOS development and decided it would be a messaging app. I'm adding timestamps to the messages below the message body, but still within the bubble, as I like this look better than outside of the bubble. iOS automatically formats these numbers for inclusion in calendar. Is there a way to escape this formatting for JUST those numbers? I'd like to keep it for when users enter times and dates, as that's really useful.
Below is the block that's adding the message body, as well as a screenshot of what I'm referring to.
override func didPressSendButton(button: UIButton!, withMessageText text: String!, senderId: String!, senderDisplayName: String!, date: NSDate!) {
JSQSystemSoundPlayer.jsq_playMessageSentSound()
let date = NSDate()
let calendar = NSCalendar.currentCalendar()
let components = calendar.components(.CalendarUnitHour | .CalendarUnitMinute, fromDate: date)
let hour = components.hour
var minutes = components.minute
if minutes < 10 {
var minutes = String(minutes)
minutes = String(format: "%02d", minutes)
}
var newText = text + "\n\n \(hour):\(minutes)"
var newMessage = JSQMessage(senderId: senderId, displayName: senderDisplayName, text: newText);
messages += [newMessage]
self.finishSendingMessage()
}
In the JSQMessagesViewController where the cell is getting created, the data detector type is set to all.
Line 539 of JSQMessagesViewController.m
cell.textView.dataDetectorTypes = UIDataDetectorTypeAll;
cell.backgroundColor = [UIColor clearColor];
cell.layer.rasterizationScale = [UIScreen mainScreen].scale;
cell.layer.shouldRasterize = YES;
return cell;
You can just set it to UIDataDetectorTypeNone.
You have the dataDetector enabled, so it's detecting URLs, phone numbers, dates, and so on, and turning them into links.
Disable all or specific data detection, depending on your needs.
In your specific case, it sounds like you'd want to disable the UIDataDetectorTypeCalendarEvent data detection.
Update:
Here's a possible answer. Format the text so it doesn't appear to be a time. It may be possible, for example, to use a unicode character for the newText colon which the data detector won't catch as a time. Another option is to use a zero-width space to separate the hours with an 'invisible' character.
var newText = text + "\n\n \(hour)\u{200b}:\(minutes)" // zero-width space
Update 2:
I downloaded JSQMessage and tried this in the sample code. A zero-width space before the colon does appear to work to avoid the time from being detected.
[[JSQMessage alloc] initWithSenderId:kJSQDemoAvatarIdSquires
senderDisplayName:kJSQDemoAvatarDisplayNameSquires
date:[NSDate distantPast]
text:#"It even has data detectors. You can call me tonight. My cell number is 123-456-7890. My website is www.hexedbits.com.\n\n9\u200b:41"],
In Swift 3: To disable all detections
cell.textView?.dataDetectorTypes = []

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