Post not yet marked as solved
Am at the beginning of a voice recording app. I store incoming voice data into a buffer array, and write 50 of them to a file. The code works fine, Sample One.
However, I would like the recorded files to be smaller. So here I try to add an AVAudioMixer to downsize the sampling. But this code sample gives me two errors. Sample Two
The first error I get is when I call audioEngine.attach(downMixer). The debugger gives me nine of these errors:
throwing -10878
The second error is a crash when I try to write to audioFile. Of course they might all be related, so am looking to include the mixer successfully first.
But I do need help as I am just trying to piece these all together from tutorials, and when it comes to audio, I know less than anything else.
Sample One
//these two lines are in the init of the class that contains this function...
node = audioEngine.inputNode
recordingFormat = node.inputFormat(forBus: 0)
func startRecording()
{
audioBuffs = []
x = -1
node.installTap(onBus: 0, bufferSize: 8192, format: recordingFormat, block: {
[self]
(buffer, _) in
x += 1
audioBuffs.append(buffer)
if x >= 50 {
audioFile = makeFile(format: recordingFormat, index: fileCount)
mainView?.setLabelText(tag: 3, text: "fileIndex = \(fileCount)")
fileCount += 1
for i in 0...49 {
do {
try audioFile!.write(from: audioBuffs[i]);
} catch {
mainView?.setLabelText(tag: 4, text: "write error")
stopRecording()
}
}
...cleanup buffer code
}
})
audioEngine.prepare()
do {
try audioEngine.start()
} catch let error { print ("oh catch \(error)") }
}
Sample Two
//these two lines are in the init of the class that contains this function
node = audioEngine.inputNode
recordingFormat = node.inputFormat(forBus: 0)
func startRecording() {
audioBuffs = []
x = -1
// new code
let format16KHzMono = AVAudioFormat.init(commonFormat: AVAudioCommonFormat.pcmFormatInt16, sampleRate: 11025.0, channels: 1, interleaved: true)
let downMixer = AVAudioMixerNode()
audioEngine.attach(downMixer)
// installTap on the mixer rather than the node
downMixer.installTap(onBus: 0, bufferSize: 8192, format: format16KHzMono, block: {
[self]
(buffer, _) in
x += 1
audioBuffs.append(buffer)
if x >= 50 {
// use a different format in creating the audioFile
audioFile = makeFile(format: format16KHzMono!, index: fileCount)
mainView?.setLabelText(tag: 3, text: "fileIndex = \(fileCount)")
fileCount += 1
for i in 0...49 {
do {
try audioFile!.write(from: audioBuffs[i]);
} catch {
stopRecording()
}
}
...cleanup buffers...
}
})
let format = node.inputFormat(forBus: 0)
// new code
audioEngine.connect(node, to: downMixer, format: format)//use default input format
audioEngine.connect(downMixer, to: audioEngine.outputNode, format: format16KHzMono)//use new audio format
downMixer.outputVolume = 0.0
audioEngine.prepare()
do {
try audioEngine.start()
} catch let error { print ("oh catch \(error)") }
}
Am trying to distinguish the differences in volumes between background noise, and someone speaking in Swift.
Previously, I had come across a tutorial which had me looking at the power levels in each channel. It come out as the code listed in Sample One which I called within the installTap closure. It was ok, but the variance between background and the intended voice to record, wasn't that great. Sure, it could have been the math used to calculate it, but since I have no experience in audio data, it was like reading another language.
Then I came across another demo. It's code was much simpler, and the difference in values between background noise and speaking voice was much greater, therefore much more detectable. It's listed here in Sample Two, which I also call within the installTap closure.
My issue here is wanting to understand what is happening in the code. In all my experiences with other languages, voice was something I never dealt with before, so this is way over my head.
Not looking for someone to explain this to me line by line. But if someone could let me know where I can find decent documentation so I can better grasp what is going on, I would appreciate it.
Thank you
Sample One
func audioMetering(buffer:AVAudioPCMBuffer) {
// buffer.frameLength = 1024
let inNumberFrames:UInt = UInt(buffer.frameLength)
if buffer.format.channelCount > 0 {
let samples = (buffer.floatChannelData![0])
var avgValue:Float32 = 0
vDSP_meamgv(samples,1 , &avgValue, inNumberFrames)
var v:Float = -100
if avgValue != 0 {
v = 20.0 * log10f(avgValue)
}
self.averagePowerForChannel0 = (self.LEVEL_LOWPASS_TRIG*v) + ((1-self.LEVEL_LOWPASS_TRIG)*self.averagePowerForChannel0)
self.averagePowerForChannel1 = self.averagePowerForChannel0
}
if buffer.format.channelCount > 1 {
let samples = buffer.floatChannelData![1]
var avgValue:Float32 = 0
vDSP_meamgv(samples, 1, &avgValue, inNumberFrames)
var v:Float = -100
if avgValue != 0 {
v = 20.0 * log10f(avgValue)
}
self.averagePowerForChannel1 = (self.LEVEL_LOWPASS_TRIG*v) + ((1-self.LEVEL_LOWPASS_TRIG)*self.averagePowerForChannel1)
}
}
Sample Two
private func getVolume(from buffer: AVAudioPCMBuffer, bufferSize: Int) -> Float {
guard let channelData = buffer.floatChannelData?[0] else {
return 0
}
let channelDataArray = Array(UnsafeBufferPointer(start:channelData, count: bufferSize))
var outEnvelope = [Float]()
var envelopeState:Float = 0
let envConstantAtk:Float = 0.16
let envConstantDec:Float = 0.003
for sample in channelDataArray {
let rectified = abs(sample)
if envelopeState < rectified {
envelopeState += envConstantAtk * (rectified - envelopeState)
} else {
envelopeState += envConstantDec * (rectified - envelopeState)
}
outEnvelope.append(envelopeState)
}
// 0.007 is the low pass filter to prevent
// getting the noise entering from the microphone
if let maxVolume = outEnvelope.max(),
maxVolume > Float(0.015) {
return maxVolume
} else {
return 0.0
}
}
I have no problem creating, and writing to AVAudioFiles.
do {
audioFile = try AVAudioFile(forWriting: destinationPath, settings: format.settings)
print ("created: \(curFileLinkName)")
} catch { print ("error creating file")}
But is there a way to close the file?
I've searched and all I could find was this very post on StackOverflow, which makes me wonder.
Post not yet marked as solved
Below is a quick snippet of where I record audio. I would like to get a sampling of the background audio so that later I can filter out background noise. I figure 10 to 15 seconds should be a good amount of time.
Although I am assuming that it can change depending on the iOS device, the format returned from .inputFormat is :
<AVAudioFormat 0x600003e8d9a0: 1 ch, 48000 Hz, Float32>
Based on the format info, is it possible to make bufferSize for .installTap be just the write size for whatever time I wish to record for?
I realize I can create a timer for 10 seconds, stop recording, paster the files I have together, etc. etc. But if I can avoid all that extra coding it would be nice.
let node = audioEngine.inputNode
let recordingFormat = node.inputFormat(forBus: 0)
makeFile(format: recordingFormat)
node.installTap(onBus: 0, bufferSize: 8192, format: recordingFormat, block: {
[self]
(buffer, _) in
audioMetering(buffer: buffer)
print ("\(self.averagePowerForChannel0) \(self.averagePowerForChannel1)")
if self.averagePowerForChannel0 < -50 && self.averagePowerForChannel1 < -50 {
...
} else {
...
}
do {
... write audio file
} catch {return};})
audioEngine.prepare()
do {
try audioEngine.start()
} catch let error {
print ("oh catch \(error)")
}
Currently I am placing a UITableView inside my UIViewController, with multiple other items. I am not using a UITableViewController.
However I am unable to register the identifier "masterlist", or should I say I am not sure where I can register it. I am not using storyboard, and if I am still to register it in my UIViewController's viewDidLoad, I am unable to figure out the proper syntax.
Is this something I can do?
class BeginNewCustomer: UIViewController {
let myList = createTblView()
override func viewDidLoad() {
super.viewDidLoad()
myList.delegate = self
myList.dataSource = self
}
func createTblView() -> UITableView {
let myTable = MyTableView(frame: CGRect(x: 0, y: 0, width: 0, height: 0 ))
myTable.backgroundColor = .white
return myTable
}
extension BeginNewInv: UITableViewDelegate, UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return dbClass.invsList.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell()
// let cell = tableView.dequeueReusableCell(withIdentifier: "masterlist", for: indexPath)
var config = cell.defaultContentConfiguration()
.... fill the configuration
cell.contentConfiguration = config
return cell
}
}
Am trying to port away from .textLabel.text, as per Apple but I can't seem to find the way to get the text I set.
I now set my cells this way:
let cell = UITableViewCell()
var config = cell.defaultContentConfiguration()
config.text = dbClass.nameList[indexPath.row].clientName
config.textProperties.color = .black
config.textProperties.alignment = .center
cell.contentConfiguration = config
But when I try to get the text of a selected cell (once the user hits the OK button) I can't seem to reverse engineer how to get the text.
let cell = myClientList.cellForRow(at: myInvsList.indexPathForSelectedRow!)
let config = cell?.contentConfiguration
dbClass.curMasterinvList = ?????? (can't find what property to read here
I even tried
let config = cell?.defaultContentConfiguration()
Hoping that the text would be in there, but the text there is blank, so am assuming that's just the standard config before I've changed it.
I have Googled as much as possible, but can't seem to find this very simple need.
I am using the code below to create my own debug log for my app. On the simulator, I have no problem viewing that log. I simply print out the documents directory in the debugger, then open it in my finder.
However I do not know how to access the created log on my iPhone itself. Even if I go to Window -> Devices and Simulator's, when I look at my app's container it's empty. Although I would like to be able to access the file from any actual device in the future.
Am I using the wrong directory? I even used allDomainsMask in place of userDomainMask below, but to no avail.
debugFileURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0].appendingPathComponent("myApp.log")
if let handle = try? FileHandle(forWritingTo: dbClass.debugFileURL!) {
handle.seekToEndOfFile() // moving pointer to the end
handle.write(text.data(using: .utf8)!) // adding content
handle.closeFile() // closing the file
} else {
try! text.write(to: dbClass.debugFileURL!, atomically: false, encoding: .utf8)
}
Updated info below, in bold.
I went and changed one of the entities in the CoreData of my app. For all my entities I have them selected as "Manual" for Codegen
So I deleted all four files (for two entities), cleaned the build folder, regenerated the CoreData files with Editor -> Create NSManagedObject Subclass.
Now every time I run the app I get a fatalError in the following code in the AppDelegate:
lazy var persistentContainer: NSPersistentContainer = {
let container = NSPersistentContainer(name: “Invoice_Gen")
container.loadPersistentStores(completionHandler: { (storeDescription, error) in
if let error = error as NSError? {
fatalError("Unresolved error \(error), \(error.userInfo)")
}
})
return container
}()
The error code being
[error] error: addPersistentStoreWithType:configuration:URL:options:error: returned error NSCocoaErrorDomain (134140)
Even if I remove the files for the CoreData entities, and comment out anything related to them code wise, I will still get this crash.
If someone has any idea of whether I have to delete something else, or am whatever I would so appreciate it. This one has me more stumped than anything before it.
The change I made was to turn one of the entities' attribute from String to Int
When I changed it back, everything works. So from my research on Google there is something about the mapping model. But I can not find it at all.
Xcode updated yesterday, and am now at
Xcode Version 13.3 (13E113)
Since then, whenever I debug my app the the simulator, I get the message below. Am curious if I should be concerned.
If it makes a difference: Yes, I have an IBM keyboard attached via USB.
Also this does not happen when I debug the app on the iPhone itself.
2022-03-15 14:50:45.745237-0400 Hello World[48883:648134] [HardwareKeyboard] -[UIApplication getKeyboardDevicePropertiesForSenderID:shouldUpdate:usingSyntheticEvent:], failed to fetch device property for senderID (778835616971358211) use primary keyboard info instead.
Post not yet marked as solved
_Posted this here, on Stackoverflow. But after 2+ weeks got only 10 views and no responses. _
I have my URLSession delegates working, but am curious about the order I get back response, data, and error.
Right now am testing purposeful errors on my server side, so I can check the response if it's not 200. If it's not, I do not need to process the data, etc.
So I could use a flag, but have to make sure that I'l always get response, data, and error in a specific order?
Does such an order exist?
extension UploadInv: UIDocumentPickerDelegate, URLSessionDataDelegate,URLSessionTaskDelegate, URLSessionDelegate {
// Error received
func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
if let err = error {
print("Error: \(err.localizedDescription)")
}
}
// Response received
func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive response: URLResponse, completionHandler: (URLSession.ResponseDisposition) -> Void) {
completionHandler(URLSession.ResponseDisposition.allow)
DispatchQueue.main.async { [self] in
if let httpResponse = response as? HTTPURLResponse {
if httpResponse.statusCode != 200 {
DispatchQueue.main.async { [self] in
self.myStatus.text = "Error \(String(httpResponse.statusCode))"
myBackButt.isEnabled = true
}
}
}
}
}
// Data received
func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive data: Data) {
DispatchQueue.main.async { [self] in
I posted a stupid question, because I make some of the stupidest typos in my programming.
I just wish authors could delete questions/posts once we realize our silly typos.
This question is also, here, one StackOverflow. But it's only gotten 8 views, and I am stuck till I find out what am I doing wrong.
I am able to create a URLSesion, build a request with a file to upload and successfully call it from my app. On my server side, the proper script is called, uploaded file is saved, etc,. However, I am not receiving the HTTP responses, data, etc.
Actually had this working without the delegate, when the HTTP response functions were within the task itself. But am now trying to expand functionality and am missing something while trying implement the delegate.
The trimmed code is below, and it all works, with the exception of setting up UIViewController as the URLSession delegate. Just trying to figure out why my UIViewController is not receiving the HTTP responses.
Below is the code for:
UIViewController
Class which creates the upload session (UploadService)
Extension for UIViewController which I want to use to process the responses
How the previous task looked, when it worked. Before I tried to implement the delegate.
UIViewController
class UploadInv : UIViewController {
var xFile : XFile?
...create UI....
let uploadService = UploadService()
lazy var uploadSession: URLSession = {
let configuration = URLSessionConfiguration.default
return URLSession(configuration: configuration, delegate: self, delegateQueue: .main)
}()
override func viewWillAppear(_ animated: Bool) {
...
}
override func viewDidLoad() {
super.viewDidLoad()
uploadService.uploadSession = uploadSession
... code the lays out all buttons, labels, etc...
}
@objc func buttonAction(sender: UIButton!) {
guard let theButton = sender else { return}
let myTag = theButton.tag
switch myTag {
//button to start upload
case ButtType.up.rawValue:
uploadService.start(upFile: xFile!, script: "uploadOrig.pl", upLoadInvClass: self)
uploadService.task?.resume()
//button to select file to upload
case ButtType.file.rawValue:
... file xFile with file info
}
}
UploadService
class UploadService {
var task: URLSessionUploadTask?
var uploadSession = URLSession.shared
func start(upFile: XFile, script: String, upLoadInvClass: UploadInv) {
var request = upFile.makeUrlReq(upFile: upFile, script: script)
self.task = uploadSession.uploadTask(with: request, from: request.httpBody! )
}
}
extension
extension UploadInv: UIDocumentPickerDelegate, URLSessionDelegate {
func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
... file xFile info for upload ....
... http request created ....
}
// Below are the three simple functions which I would handle
// responses the server, but these never seem to get called.
func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
if let err = error {
print("Error: \(err.localizedDescription)")
}
}
func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive response: URLResponse, completionHandler: (URLSession.ResponseDisposition) -> Void) {
print("didReceive response")
completionHandler(URLSession.ResponseDisposition.allow)
}
func urlSession(_ session: URLSession, dataTask: URLSessionDataTask, didReceive data: Data) {
print("didReceive data")
if let responseText = String(data: data, encoding: .utf8) {
print(responseText)
}
}
}
Pre-Delegate model which worked
class UploadService {
var uploadSession = URLSession.shared
func start(upFile: XFile, script: String, upLoadInvClass: UploadInv) {
var request = upFile.makeUrlReq(upFile: upFile, script: script)
uploadSession.uploadTask(with: request, from: request.httpBody )
{ (data, response, error) in
if let response = response {
upLoadInvClass.upResp(resp: response)
}
if let error = error {
upLoadInvClass.upErr(error: error)
}
if let data = data {
upLoadInvClass.upData(data: data)
}
}.resume()
}
}
Post not yet marked as solved
From a tutorial I pulled the extension below to allow the enduser to select a file off of the iPhone's storage system.
Everything works fine.
However I noticed that in the delegate that "dismiss" is only being called if the user chooses cancel. While the view does disappear when a file is selected, I am not sure that the view is being properly dismissed internally by Swift.
Since I do call present, am I responsible for dismissing it when the user chooses a file as well?
let supportedTypes: [UTType] = [UTType.item]
let pickerViewController = UIDocumentPickerViewController(forOpeningContentTypes: supportedTypes)
pickerViewController.delegate = self
pickerViewController.allowsMultipleSelection = false
present(pickerViewController, animated: true, completion: nil)
extension uploadFile: UIDocumentPickerDelegate {
func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
for url in urls {
guard url.startAccessingSecurityScopedResource() else {
print ("error")
return
}
...save chosen file url here in an existing structre
do { url.stopAccessingSecurityScopedResource() }
}
}
func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {
controller.dismiss(animated: true, completion: nil)
}
}
Post not yet marked as solved
I realize I could declare a global var, such as:
var mySpecialSubClass : MySpecialSubClass?
..and then check if it is defined.
Don't know of any reason to do one way or another, but I was wondering if there was a search for an instance of "MySpecialSubClass" function or method available?
I have the following structure :
struct XFile : Codable {
...variables here
init(fileUrl: URL, key: String) {
...
}
Then in another class I am trying the following:
class UploadTask {
var xfile: XFile
var inProgress = false
init(file: URL) {
xFile = XFile(fileUrl: file, key: "filename")
}
}
If typed as above Xcode gives me the following error:
Cannot find 'xFile' in scope
If I remove the xFile= part,
Xcode give me the following warning and error:
Result of 'XFile' initializer is unused
Return from initializer without initializing all stored properties
Obviously I am breaking some rule, just not sure what it is.
SergioDCQ.