I'm making an app to record videos at the device maximum frame rate (i.e., 120fps in the iPhone 5s and 240 in the 6 and 6s). I've managed to configure the AVCaptureDevice to set the maxFrameRateDuration, I print to the logs the currentDevice.activeFormat.videoSupportedFrameRateRanges and everything works great.
But when I attempt to save the video, it does save it, but at normal frame rate, not at 120 or 240fps.
Please, can anyone help me with this? Any help would be much appreciated.
Thanks in advance.
P.S.: Here is my full code so far
import UIKit
import AVFoundation
import AVKit
import AssetsLibrary
class ViewController: UIViewController, AVCaptureFileOutputRecordingDelegate {
@IBOutlet weak var cameraButton:UIButton!
let captureSession = AVCaptureSession()
var currentDevice:AVCaptureDevice?
var videoFileOutput:AVCaptureMovieFileOutput?
var cameraPreviewLayer:AVCaptureVideoPreviewLayer?
var outputPath: String = ""
var backgroundRecordId: UIBackgroundTaskIdentifier = UIBackgroundTaskInvalid
var isRecording = false
override func viewDidLoad() {
super.viewDidLoad()
// Preset the session for taking photo in full resolution
captureSession.sessionPreset = AVCaptureSessionPresetHigh
// Get the available devices that is capable of taking video
let devices = AVCaptureDevice.devicesWithMediaType(AVMediaTypeVideo) as! [AVCaptureDevice]
// Get the back-facing camera for taking videos
for device in devices {
if device.position == AVCaptureDevicePosition.Back {
currentDevice = device
configureDevice()
}
}
let captureDeviceInput:AVCaptureDeviceInput
do {
captureDeviceInput = try AVCaptureDeviceInput(device: currentDevice)
} catch {
print(error)
return
}
// Configure the session with the output for capturing video
videoFileOutput = AVCaptureMovieFileOutput()
// Configure the session with the input and the output devices
captureSession.addInput(captureDeviceInput)
captureSession.addOutput(videoFileOutput)
// Provide a camera preview
cameraPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
view.layer.addSublayer(cameraPreviewLayer!)
cameraPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill
cameraPreviewLayer?.frame = view.layer.frame
// Bring the camera button to front
view.bringSubviewToFront(cameraButton)
captureSession.startRunning()
}
func configureDevice() {
var bestFormat: AVCaptureDeviceFormat? = nil
var bestFrameRateRange: AVFrameRateRange? = nil
var bestPixelArea: Int32 = 0
for format in currentDevice!.formats {
let dims: CMVideoDimensions = CMVideoFormatDescriptionGetDimensions(format.formatDescription)
let pixelArea: Int32 = dims.width * dims.height
let ranges = format.videoSupportedFrameRateRanges as! [AVFrameRateRange];
for range in ranges {
//print ("[",dims.width,",",dims.width,"] : ",range.maxFrameRate);
if bestFrameRateRange==nil || range.maxFrameRate > bestFrameRateRange!.maxFrameRate || ((range.maxFrameRate == bestFrameRateRange!.maxFrameRate) && (pixelArea > bestPixelArea)) {
bestFormat = format as? AVCaptureDeviceFormat
bestFrameRateRange = range
bestPixelArea = pixelArea
}
}
}
do {
try currentDevice!.lockForConfiguration() {
currentDevice!.activeFormat = bestFormat
currentDevice!.activeVideoMinFrameDuration = bestFrameRateRange!.minFrameDuration
currentDevice!.activeVideoMaxFrameDuration = bestFrameRateRange!.minFrameDuration
}
catch{}
print(currentDevice!.activeFormat.videoSupportedFrameRateRanges)
currentDevice!.unlockForConfiguration()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// MARK: - AVCaptureFileOutputRecordingDelegate methods
func captureOutput(captureOutput: AVCaptureFileOutput!, didFinishRecordingToOutputFileAtURL outputFileURL: NSURL!, fromConnections connections: [AnyObject]!, error: NSError!) {
if error != nil {
print(error)
return
}
let backgroundRecordId: UIBackgroundTaskIdentifier = self.backgroundRecordId
self.backgroundRecordId = UIBackgroundTaskInvalid
ALAssetsLibrary().writeVideoAtPathToSavedPhotosAlbum(outputFileURL, completionBlock: {
(assetURL:NSURL!, error:NSError!) in
if error != nil{
print(error)
}
do {
try NSFileManager.defaultManager().removeItemAtURL(outputFileURL)
} catch _ {
}
if backgroundRecordId != UIBackgroundTaskInvalid {
UIApplication.sharedApplication().endBackgroundTask(backgroundRecordId)
}
})
performSegueWithIdentifier("playVideo", sender: outputFileURL)
}
// MARK: - Segue methods
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "playVideo" {
let videoPlayerViewController = segue.destinationViewController as! AVPlayerViewController
let videoFileURL = sender as! NSURL
videoPlayerViewController.player = AVPlayer(URL: videoFileURL)
}
}
// MARK: - Action methods
@IBAction func unwindToCamera(segue:UIStoryboardSegue) {
}
@IBAction func capture(sender: AnyObject) {
if !isRecording {
isRecording = true
UIView.animateWithDuration(0.5, delay: 0.0, options: [.Repeat, .Autoreverse, .AllowUserInteraction], animations: { () -> Void in
self.cameraButton.transform = CGAffineTransformMakeScale(0.5, 0.5)
}, completion: nil)
let outputPath: String = NSTemporaryDirectory() + "output.mov"
let outputFileURL = NSURL(fileURLWithPath: outputPath)
videoFileOutput?.startRecordingToOutputFileURL(outputFileURL, recordingDelegate: self)
} else {
isRecording = false
UIView.animateWithDuration(0.5, delay: 1.0, options: [], animations: { () -> Void in
self.cameraButton.transform = CGAffineTransformMakeScale(1.0, 1.0)
}, completion: nil)
cameraButton.layer.removeAllAnimations()
videoFileOutput?.stopRecording()
}
}
}
