I'm making a custom camera with a small preview area inside of the iPad, however, the stream in that previewing is rotated clockwise.
I have looked at both AVCam demo and the SquareCam demo on Apple and I don't see a solution in either. All of the AVFoundation orientation threads on StackOverflow are talking specifically about output orientation, not input orientation.
Here is the session code I'm using:
AVCaptureDevice *frontalCamera = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
_session = [[AVCaptureSession alloc] init];
[_session beginConfiguration];
NSError *error;
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:frontalCamera error:&error];
[_session addInput:input];
_output = [[AVCaptureStillImageOutput alloc] init];
[_output setOutputSettings:[[NSDictionary alloc] initWithObjectsAndKeys:AVVideoCodecJPEG,AVVideoCodecKey,nil]];
[_session addOutput:_output];
AVCaptureVideoPreviewLayer *previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:_session];
previewLayer.frame = self.imageViewCamera.bounds;
previewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
[self.imageViewCamera.layer addSublayer:previewLayer];
_session.sessionPreset = AVCaptureSessionPreset640x480;
[_session commitConfiguration];
[_session startRunning];
Any help would be much appreciated!
The Apple docs for iOS 6 say to use videoOrientation (AVCaptureConnection) instead.
The layer’s orientation. (Deprecated in iOS 6.0. Use videoOrientation
(AVCaptureConnection) instead.)
so use:
[[AVCaptureVideoPreviewLayer connection] setVideoOrientation: AVCaptureVideoOrientationLandscapeRight];
or
AVCaptureVideoPreviewLayer.connection.videoOrientation= AVCaptureVideoOrientationLandscapeRight;
This has been deprecated but you can change the orientation of your previewLayer counter-clockwise.
previewLayer.orientation = AVCaptureVideoOrientationLandscapeRight;
I'm not sure what the non-deprecated solution is though.
Related
I'll start with saying that I am new to objective-c and iOS-programming.
What I want to do is to display camera as a part of a view, like a rectangle in the upper part of a screen, where should I start?
(What GUI-component for the "camera view"? AVCamCaptureManager or UIImagePickerController?)
You can use the AVFoundation to do that. A good starting point is to see the WWDC videos (since 2011) related with AVFoundation and Camera.
The Apple's example code for AVCam project is a very good starting point.
Here's an example of what you can do.
First you need to instantiate a capture session:
AVCaptureSession *session = [[AVCaptureSession alloc] init];
session.sessionPreset = AVCaptureSessionPreset1280x720;
Then you must create the input and add it to the session in order to get images from your device camera:
AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
NSError *error = nil;
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
if (!input) {
NSLog(#"Couldn't create video capture device");
}
[session addInput:input];
Then you make use of AVCaptureVideoPreviewLayer to present in a Layer the images from your device camera:
AVCaptureVideoPreviewLayer *newCaptureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
Finally you just need to set the frame (portion of UI you need) of that specific layer and add it to the desired view and start the session capture.
I want to use the AVFoundation Famework for previewing and capturing photos.
I created a AVCaptureSession and added AVCaptureVideoDataOutput, AVCaptureStillImageOutput to this session. I set the preset to AVCaptureSessionPresetLow.
Now I want to take a Photo in full Resolution. But within captureStillImageAsynchronouslyFromConnection the resolution is the same as in my preview delegate.
Here is my Code:
AVCaptureSession* cameraSession = [[AVCaptureSession alloc] init];
cameraSession.sessionPreset = AVCaptureSessionPresetLow;
AVCaptureVideoDataOutput* output = [[AVCaptureVideoDataOutput alloc] init];
[cameraSession addOutput:output];
AVCaptureStillImageOutput* cameraStillImage = [[AVCaptureStillImageOutput alloc] init];
[cameraSession addOutput:cameraStillImage];
// delegation
dispatch_queue_t queue = dispatch_queue_create("MyQueue", NULL);
[output setSampleBufferDelegate:self queue:queue];
dispatch_release(queue);
[cameraSession startRunning];
Take Photo:
//[cameraSession beginConfiguration];
//[cameraSession setSessionPreset:AVCaptureSessionPresetPhoto]; <-- slow
//[cameraSession commitConfiguration];
[cameraStillImage captureStillImageAsynchronouslyFromConnection:photoConnection completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *error)
{
...
}];
I tried it by changing the preset to photo just befor capturing the image. But this is very slow (it takes 2-3 seconds to change the preset). I do not want to have such a big delay.
How can I do this? Thanks.
Does anybody know how I can get a live camera feed into an UIImageView?
I have a custom UI where I need to show the camera feed (front facing camera) so I cannot use the UIImagePickerControl.
You need to create a capture session, and start it running. Once that's done you can add the layer from the capture session to your view:
- (void)setupCaptureSession
{
NSError* error = nil;
// Create the session
_captureSession = [[AVCaptureSession alloc] init];
_captureSession.sessionPreset = AVCaptureSessionPresetMedium;
AVCaptureDevice* device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
AVCaptureDeviceInput* input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
[_captureSession addInput:input];
AVCaptureVideoDataOutput* output = [[AVCaptureVideoDataOutput alloc] init];
[_captureSession addOutput:output];
// Configure your output.
dispatch_queue_t queue = dispatch_queue_create("myCameraOutputQueue", NULL);
//If you want to sebsequently use the data, then implement the delegate.
[output setSampleBufferDelegate:self queue:queue];
}
Having done that, you can create a preview layer as follows:
_previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:_captureSession];
[_captureSession startRunning];
And then add the preview layer to your view:
_myView.layer addSubLayer:_previewLayer];
Here's the problem. I am using AVCaptureVideoDataOutput to get video frames from camera and make video from them with AVAssetWriter. Its working OK, but the video that I get is upside down because default orientation of device for my app is landscape left, not landscape right as its stated by default in AVCaptureVideoDataOutput. Im trying to change orientation in AVCaptureConnection class, but isVideoOrientationSupported is always false, is it somehow possible to fix it?
Here is some code:
AVCaptureDeviceInput *captureInput = [AVCaptureDeviceInput
deviceInputWithDevice:[AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo]
error:nil];
/*We setupt the output*/
AVCaptureVideoDataOutput *captureOutput = [[AVCaptureVideoDataOutput alloc] init];
captureOutput.alwaysDiscardsLateVideoFrames = YES;
captureOutput.minFrameDuration = CMTimeMake(1.0, 24.0); //Uncomment it to specify a minimum duration for each video frame
[captureOutput setSampleBufferDelegate:self queue:dispatch_get_main_queue()];
// Set the video output to store frame in BGRA (It is supposed to be faster)
NSString* key = (NSString*)kCVPixelBufferPixelFormatTypeKey;
NSNumber* value = [NSNumber numberWithUnsignedInt:kCVPixelFormatType_32BGRA];
NSDictionary* videoSettings = [NSDictionary dictionaryWithObject:value forKey:key];
[captureOutput setVideoSettings:videoSettings];
/*And we create a capture session*/
self.captureSession = [[AVCaptureSession alloc] init];
self.captureSession.sessionPreset = AVCaptureSessionPresetLow;
/*We add input and output*/
if ([self.captureSession canAddInput:captureInput])
{
[self.captureSession addInput:captureInput];
}
if ([self.captureSession canAddOutput:captureOutput])
{
[self.captureSession addOutput:captureOutput];
}
/*We add the preview layer*/
self.prevLayer = [AVCaptureVideoPreviewLayer layerWithSession: self.captureSession];
if ([self.prevLayer isOrientationSupported])
{
[self.prevLayer setOrientation:AVCaptureVideoOrientationLandscapeLeft];
}
self.prevLayer.frame = self.view.bounds;
self.prevLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;
[self.view.layer addSublayer: self.prevLayer];
AVCaptureConnection *videoConnection = NULL;
[self.captureSession beginConfiguration];
for ( AVCaptureConnection *connection in [captureOutput connections] )
{
for ( AVCaptureInputPort *port in [connection inputPorts] )
{
if ( [[port mediaType] isEqual:AVMediaTypeVideo] )
{
videoConnection = connection;
}
}
}
if([videoConnection isVideoOrientationSupported]) // **Here it is, its always false**
{
[videoConnection setVideoOrientation:AVCaptureVideoOrientationLandscapeLeft];
}
[self.captureSession commitConfiguration];
[self.captureSession startRunning];
Upd: figured that when exporting video, the AVAssetExportSession loses preferredTransform info.
I ran into the same problem and poked around the AVCamDemo from WWDC. I don't know why (yet) but if you query your videoConnection right after you create all the inputs/outputs/connections then both isVideoOrientationSupported and supportsVideoOrientation return NO.
However, if you query supportsVideoOrientation or isVideoOrientationSupported at some later point (after the GUI is setup for instance) then it will return YES. For instance I query it right after the user clicks the record button just before I call [[self movieFileOutput] startRecordingToOutputFileURL...]
Give it a try, works for me.
From here: http://developer.apple.com/library/ios/#qa/qa1744/_index.html#//apple_ref/doc/uid/DTS40011134
Currently, the capture outputs for a movie file
(AVCaptureMovieFileOutput) and still image (AVCaptureStillImageOutput)
support setting the orientation, but the data output for processing
video frames (AVCaptureVideoDataOutput) does not.
Exposure values from camera can be acquired when you take picture (without saving it to SavedPhotos). A light meter application on iPhone does this, probably by using some private API.
That application does it on iPhone 3GS only, so I guess it may be somehow related to EXIF data which is populated with this information when the image is created.
This all applies to 3GS.
Has anything changed with iPhone OS 4.0?
Is there a regular way to get these values now?
Does anyone have a working code example for taking these camera/photo setting values?
Thank you
If you want realtime* exposure information, you can capture a video using AVCaptureVideoDataOutput. Each frame CMSampleBuffer is full of interesting data describing the current state of the camera.
*up to 30 fps
With AVFoundation in iOS 4.0 you can mess with exposure, refer specifically to AVCaptureDevice, here is a link AVCaptureDevice ref. Not sure if its exactly what you want but you can look around AVFoundation and probably find some useful stuff
I think I finally found the lead to the real EXIF data. It'll be a while before I have actual code to post, but I figured this should be publicized in the meantime.
Google captureStillImageAsynchronouslyFromConnection. It's a function of AVCaptureStillImageOutput and following is an excerpt from the documentation (long sought for):
imageDataSampleBuffer -
The data that was captured.
The buffer attachments may contain metadata appropriate to the image data format. For example, a buffer containing JPEG data may carry a kCGImagePropertyExifDictionary as an attachment. See ImageIO/CGImageProperties.h for a list of keys and value types.
For an example of working with AVCaptureStillImageOutput see WWDC 2010 sample code, under AVCam.
Peace,
O.
Here is the complete solution. Dont forget to import appropriate frameworks and headers.
In the exifAttachments var in capturenow method you'll find all data you are looking for.
#import <AVFoundation/AVFoundation.h>
#import <ImageIO/CGImageProperties.h>
AVCaptureStillImageOutput *stillImageOutput;
AVCaptureSession *session;
- (void)viewDidLoad
{
[super viewDidLoad];
[self setupCaptureSession];
// Do any additional setup after loading the view, typically from a nib.
}
-(void)captureNow{
AVCaptureConnection *videoConnection = nil;
for (AVCaptureConnection *connection in stillImageOutput.connections)
{
for (AVCaptureInputPort *port in [connection inputPorts])
{
if ([[port mediaType] isEqual:AVMediaTypeVideo] )
{
videoConnection = connection;
break;
}
}
if (videoConnection) { break; }
}
[stillImageOutput captureStillImageAsynchronouslyFromConnection:videoConnection
completionHandler:^(CMSampleBufferRef imageDataSampleBuffer, NSError *__strong error) {
CFDictionaryRef exifAttachments = CMGetAttachment( imageDataSampleBuffer, kCGImagePropertyExifDictionary, NULL);
if (exifAttachments)
{
// Do something with the attachments.
NSLog(#"attachements: %#", exifAttachments);
}
else
NSLog(#"no attachments");
NSData *imageData = [AVCaptureStillImageOutput jpegStillImageNSDataRepresentation:imageDataSampleBuffer];
UIImage *image = [[UIImage alloc] initWithData:imageData];
}];
}
// Create and configure a capture session and start it running
- (void)setupCaptureSession
{
NSError *error = nil;
// Create the session
session = [[AVCaptureSession alloc] init];
// Configure the session to produce lower resolution video frames, if your
// processing algorithm can cope. We'll specify medium quality for the
// chosen device.
session.sessionPreset = AVCaptureSessionPreset352x288;
// Find a suitable AVCaptureDevice
AVCaptureDevice *device = [AVCaptureDevice
defaultDeviceWithMediaType:AVMediaTypeVideo];
[device lockForConfiguration:nil];
device.whiteBalanceMode = AVCaptureWhiteBalanceModeLocked;
device.focusMode = AVCaptureFocusModeLocked;
[device unlockForConfiguration];
// Create a device input with the device and add it to the session.
AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device
error:&error];
if (!input) {
// Handling the error appropriately.
}
[session addInput:input];
stillImageOutput = [AVCaptureStillImageOutput new];
NSDictionary *outputSettings = [[NSDictionary alloc] initWithObjectsAndKeys: AVVideoCodecJPEG, AVVideoCodecKey, nil];
[stillImageOutput setOutputSettings:outputSettings];
if ([session canAddOutput:stillImageOutput])
[session addOutput:stillImageOutput];
// Start the session running to start the flow of data
[session startRunning];
[self captureNow];
}