I have the following code:
func createStringFromAudio () {
SFSpeechRecognizer.requestAuthorization {_ in
DispatchQueue.main.async {
switch SFSpeechRecognizer.authorizationStatus() {
case .authorized :
let audioURL = Bundle.main.url(forResource: "ConversionTest", withExtension: "mp3")!
let recognizer = SFSpeechRecognizer()
let request = SFSpeechURLRecognitionRequest(url: audioURL)
recognizer?.recognitionTask(with: request) { result, error in
guard error == nil else { print("Error"); return}
guard let result = result else {print("No result"); return}
print(result.bestTranscription.formattedString)
}
break
default :
break
}
}
}
}
Here is my question:
1: How do I know when the file is done? Currently it continually updates the result print but doesn't notify me when the transcription is 100% completed. How do I know when the transcription is done and I can save the string for parsing?
2: It seems to cut off before finishing. Is there a time limit? Character limit?
You can save the task to check its status, even cancell it.
Actually, the transcribing process is not controlled by us and when the system think its finished, it's finished.
If you do need precise controls, use a delegate:
func recognitionTask(with request: SFSpeechRecognitionRequest, delegate: SFSpeechRecognitionTaskDelegate) -> SFSpeechRecognitionTask
This may provide more informations during transcribing, at least it will let you know when it is finished.
Related
Updated info below, and new code
I am trying to incorporate SFSpeechRecognizer into my app, and the errors/results I am getting from three pre-recorded audiofiles aren't enough for me to figure out what's going on. From the results I am getting I can't figure out what's wrong, and info via Google is sparse.
The code where I loop through three files is at the bottom. Here are the responses I get for my three audio files. I've made sure in each file to speak loudly and clearly, yet I still get: No speech detected or no text returned.
SS-X-03.m4a : There was an error: Optional(Error
Domain=kAFAssistantErrorDomain Code=1110 "No speech detected"
UserInfo={NSLocalizedDescription=No speech detected})
SS-X-20221125000.m4a : There was an error: Optional(Error
Domain=kAFAssistantErrorDomain Code=1110 "No speech detected"
UserInfo={NSLocalizedDescription=No speech detected})
SS-X-20221125001.m4a : (there is some text here if I set
request.requiresOnDeviceRecognition to false)
My code:
func findAudioFiles(){
let fm = FileManager.default
var aFiles : URL
print ("\(urlPath)")
do {
let items = try fm.contentsOfDirectory(atPath: documentsPath)
let filteredInterestArray1 = items.filter({$0.hasSuffix(".m4a")})
let filteredInterestArray2 = filteredInterestArray1.filter({$0.contains("SS-X-")})
let sortedItems = filteredInterestArray2.sorted()
for item in sortedItems {
audioFiles.append(item)
}
NotificationCenter.default.post(name: Notification.Name("goAndRead"), object: nil, userInfo: myDic)
} catch {
print ("\(error)")
}
}
#objc func goAndRead(){
audioIndex += 1
if audioIndex != audioFiles.count {
let fileURL = NSURL.fileURL(withPath: documentsPath + "/" + audioFiles[audioIndex], isDirectory: false)
transcribeAudio(url: fileURL, item: audioFiles[audioIndex])
}
}
func requestTranscribePermissions() {
SFSpeechRecognizer.requestAuthorization { [unowned self] authStatus in
DispatchQueue.main.async {
if authStatus == .authorized {
print("Good to go!")
} else {
print("Transcription permission was declined.")
}
}
}
}
func transcribeAudio(url: URL, item: String) {
guard let recognizer = SFSpeechRecognizer(locale: Locale(identifier: "en-US")) else {return}
let request = SFSpeechURLRecognitionRequest(url: url)
if !recognizer.supportsOnDeviceRecognition { print ("offline not available") ; return }
if !recognizer.isAvailable { print ("not available") ; return }
request.requiresOnDeviceRecognition = true
request.shouldReportPartialResults = true
recognizer.recognitionTask(with: request) {(result, error) in
guard let result = result else {
print("\(item) : There was an error: \(error.debugDescription)")
return
}
if result.isFinal {
print("\(item) : \(result.bestTranscription.formattedString)")
NotificationCenter.default.post(name: Notification.Name("goAndRead"), object: nil, userInfo: self.myDic)
}
}
}
Updated info
It appears that I was calling SFSpeechURLRecognitionRequest too often, and before I completed the first request. Perhaps I need to create a new instance of SFSpeechRecognizer? Unsure.
Regardless I quickly/sloppily adjusted the code to only run it once the previous instance returned its results.
The results were much better, except one audio file still came up as no results. Not an error, just no text.
This file is the same as the previous file, in that I took an audio recording and split it in two. So the formats and volumes are the same.
So I still need a better way to debug this, to find out what it going wrong with that file.
I need to make 2 API calls simultaneously. I have 2 URLs for the calls, and if one of the calls will return any error I want to stop all the code execution.
How I tried to do it:
I have a function called performRequest() with a completion block. I call the function in my ViewController to update the UI - show an error/or a new data if all was successful. Inside it I create a URLSession tasks and then parse JSON:
I created an array with 2 urls:
func performRequest(_ completion: #escaping (Int?) -> Void) {
var urlArray = [URL]()
guard let urlOne = URL(string: "https://api.exchangerate.host/latest?base=EUR&places=9&v=1") else { return }
guard let urlTwo = URL(string: "https://api.exchangerate.host/2022-05-21?base=EUR&places=9") else { return }
urlArray.append(urlOne)
urlArray.append(urlTwo)
}
Then for each of the url inside the array I create a session and a task:
urlArray.forEach { url in
let session = URLSession(configuration: .ephemeral)
let task = session.dataTask(with: url) { data, _, error in
if error != nil {
guard let error = error as NSError? else { return }
completion(error.code)
return
}
if let data = data {
let printData = String(data: data, encoding: String.Encoding.utf8)
print(printData!)
DispatchQueue.main.async {
self.parseJSON(with: data)
}
}
}
task.resume()
}
print("all completed")
completion(nil)
}
For now I receive print("all completed") printed once in any situation: if both tasks were ok, if one of them was ok or none of them.
What I want is to show the print statement only if all tasks were completed successfully and to stop executing the code if one of them returned with error (for example if we will just delete one of the symbols in url string which will take it impossible to receive a data).
How can I do it correctly?
I create a request to the server, and in the end I expect to receive data, which I then transform into a model using a function, for this I created a session
func fetchNewsData(forCoutry country: String, category: String, complition: #escaping (NewsDataModel) -> ()) {
let urlString = "some url string"
guard let url = URL(string: urlString) else { return }
let session = URLSession(configuration: .default)
let task = session.dataTask(with: url) { data, response, error in
print ("ERROR: \(error)")
guard let data = data else { return }
guard let newsData = self.parseJSON(withData: data) else { return }
complition(newsData)
}
task.resume()
}
but the following code just doesn't work
print ("ERROR: \(error)")
guard let data = data else { return }
guard let newsData = self.parseJSON(withData: data) else { return }
complition(newsData)
I used breakpoints to find out until what point everything is going well, and I realized that this particular block of code is not working.
when I set a breakpoint between the let session and the let task, the code stopped there, but when I set my code to an print(error), this breakpoint did not work
I used the function fetchNewsData in viewDidLoad and I want to work to fill the array with elements that I expect to receive from the data that will come on this request, but my array does not receive any elements, and it remains empty, because of this my application does not work
why part of the code doesn't work, and how can I get the data I need from it?
The problem turned out to be a poor understanding of closures
I was not calling my method correctly to get the data. Having figured it out, I realized that the problem is precisely in a different approach when calling this method
I am trying to recover a data set from a URL (after parsing a JSON through the parseJSON function which works correctly - I'm not attaching it in the snippet below).
The outcome returns nil - I believe it's because the closure in retrieveData function is processed asynchronously. I can't manage to have the outcome saved into targetData.
Thanks in advance for your help.
class MyClass {
var targetData:Download?
func triggerEvaluation() {
retrieveData(url: "myurl.com") { downloadedData in
self.targetData = downloadedData
}
print(targetData) // <---- Here is where I get "nil"!
}
func retrieveData(url: String, completion: #escaping (Download) -> ()) {
let myURL = URL(url)!
let mySession = URLSession(configuration: .default)
let task = mySession.dataTask(with: myURL) { [self] (data, response, error) in
if error == nil {
if let fetchedData = data {
let safeData = parseJSON(data: fetchedData)
completion(safeData)
}
} else {
//
}
}
task.resume()
}
}
Yes, it’s nil because retrieveData runs asynchronously, i.e. the data hasn’t been retrieved by the time you hit the print statement. Move the print statement (and, presumably, all of the updating of your UI) inside the closure, right where you set self.targetData).
E.g.
func retrieveData(from urlString: String, completion: #escaping (Result<Download, Error>) -> Void) {
let url = URL(urlString)!
let mySession = URLSession.shared
let task = mySession.dataTask(with: url) { [self] data, response, error in
guard
let responseData = data,
error == nil,
let httpResponse = response as? HTTPURLResponse,
200 ..< 300 ~= httpResponse.statusCode
else {
DispatchQueue.main.async {
completion(.failure(error ?? NetworkError.unknown(response, data))
}
return
}
let safeData = parseJSON(data: responseData)
DispatchQueue.main.async {
completion(.success(safeData))
}
}
task.resume()
}
Where
enum NetworkError: Error {
case unknown(URLResponse?, Data?)
}
Then the caller would:
func triggerEvaluation() {
retrieveData(from: "https://myurl.com") { result in
switch result {
case .failure(let error):
print(error)
// handle error here
case .success(let download):
self.targetData = download
// update the UI here
print(download)
}
}
// but not here
}
A few unrelated observations:
You don't want to create a new URLSession for every request. Create only one and use it for all requests, or just use shared like I did above.
Make sure every path of execution in retrieveData calls the closure. It might not be critical yet, but when we write asynchronous code, we always want to make sure that we call the closure.
To detect errors, I'd suggest the Result pattern, shown above, where it is .success or .failure, but either way you know the closure will be called.
Make sure that model updates and UI updates happen on the main queue. Often, we would have retrieveData dispatch the calling of the closure to the main queue, that way the caller is not encumbered with that. (E.g. this is what libraries like Alamofire do.)
Can anyone explain why the completion returns empty array?
The function:
import Foundation
class IMBD{
func searchMovies(searchText:String, completion: (result: [Movies]) -> Void){
var movies = [Movies]()
let replacedMovieTitle = searchText.stringByReplacingOccurrencesOfString(" ", withString: "+")
let URLString = "http://www.omdbapi.com/?s=\(replacedMovieTitle)&y=&r=json"
let URL = NSURL(string: URLString)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(URL!, completionHandler: {(data, response, error) -> Void in
do{
let jsonData = try NSJSONSerialization.JSONObjectWithData(data!, options: .MutableContainers) as! NSDictionary
if let search = jsonData["Search"] as? [[String : AnyObject]]{
for hit in search{
guard let title = hit["Title"] as? String else{
print("returna title")
return
}
guard let year = hit["Year"] as? String else{
print("returna year")
return
}
guard let imbdID = hit["imdbID"] as? String else{
print("returna imbd")
return
}
guard let poster = hit["Poster"] as? String else{
print("returna poster")
return
}
let movie = Movies(title: title, released: year, poster: poster, imbdID: imbdID)
movies.append(movie)
}
}
}catch{
}
}).resume()
completion(result: movies)
}
}
The call:
imbd.searchMovies(searchtext!, completion: { (result) -> Void in
self.movieList = result
})
You have to call your completion handles inside the dataTaskWithURL closure, not after it. This runs asynchronously, so if you call your completion outside of the closure, it would be called before the asynchronous request had a chance to retrieve anything.
Also, remember that this closure doesn't run on the main thread, so you likely want to also dispatch this to the main queue (from within the dataTaskWithURL).
For example:
class IMDB {
func searchMovies(searchText:String, completion: (result: [Movie]?, error: NSError?) -> Void) -> NSURLSessionTask {
var movies = [Movie]()
let allowedCharacters = NSCharacterSet.alphanumericCharacterSet().mutableCopy() as! NSMutableCharacterSet
allowedCharacters.addCharactersInString("-._* ")
let replacedMovieTitle = searchText.stringByAddingPercentEncodingWithAllowedCharacters(allowedCharacters)!
.stringByReplacingOccurrencesOfString(" ", withString: "+")
let URLString = "http://www.omdbapi.com/?s=\(replacedMovieTitle)&y=&r=json"
let URL = NSURL(string: URLString)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(URL!) { data, response, error in
guard error == nil && data != nil else {
dispatch_async(dispatch_get_main_queue()) {
completion(result: nil, error: error)
}
return
}
do {
let jsonData = try NSJSONSerialization.JSONObjectWithData(data!, options: .MutableContainers) as! NSDictionary
if let search = jsonData["Search"] as? [[String : AnyObject]]{
for hit in search{
guard let title = hit["Title"] as? String else{
print("returna title")
continue
}
guard let year = hit["Year"] as? String else{
print("returna year")
continue
}
guard let imdbID = hit["imdbID"] as? String else{
print("returna imbd")
continue
}
guard let poster = hit["Poster"] as? String else{
print("returna poster")
continue
}
let movie = Movie(title: title, released: year, poster: poster, imdbID: imdbID)
movies.append(movie)
}
}
dispatch_async(dispatch_get_main_queue()) {
completion(result: movies, error: nil)
}
} catch let error as NSError {
dispatch_async(dispatch_get_main_queue()) {
completion(result: nil, error: error)
}
}
}
task.resume()
return task
}
}
A couple of other changes in the above code snippet include:
Add guard in case there was a fundamental network error (e.g. remote server down, no Internet access, etc.)
In the guard statements that are checking for nil values, rather than performing a return (in which case no further results will be gathered), you might want to just continue (i.e. skip to the next record). You generally see guard in conjunction with return, but in this case, continue is probably more appropriate.
Frankly, you might want to take this a step further and consider whether some of these might be optional, rather than discarding the whole record. Notably, poster strikes me as something that might be nil if there was no poster available. Maybe some of the others should be optional, too, (e.g. if a movie hasn't been released yet, might it not have a release date?).
The occurrences of "imbd" have been replaced with "imdb".
The Movies class has been renamed to Movie (since each instance is a single movie, not a collection of them).
I changed the completion block to make [Movie] optional and to return the NSError. Without that, you don't have a way to differentiate between "couldn't find a title of that name" and "whoops, something went wrong".
When we call the completion closure from within the dataTaskWithURL, it can be very useful to have searchMovies dispatch completion calls back to the main queue, like above. This is because UI updates must always happen on the main thread, and frequently when you write routines like this, it is so you can update UI or the model with results.
This is not always necessary to do it like this (you might want to just have this call completion directly from the background thread and let the routine that called searchMovies manually dispatch stuff to the main thread itself), but I often find it useful to have this search method just dispatch the completion back to the main thread and be done with it.
As a matter of practice, I always return the NSURLSessionTask when performing requests. You might not need it now, but at some future date, you might want the ability to cancel an on-going request, and having a reference to the task can be useful. It doesn't hurt to return it, and it can be useful.
You probably should be percent escaping the values you add to the URL. Notably the presence of & or + characters could be problematic. Note, in this case, it looks like this site isn't handling it appropriately, anyway, but it's good to get in the habit of properly percent-escaping values in a query.
Personally, I keep this percent escaping logic in a String extension, but I wanted to keep this simple, so I embedded it right in this method, but hopefully it illustrates the idea.