I am creating simple camera app and I want to add 'image stability' so when hands are shaking the camera does not twitch. Is it possible to do in iOS?
You can do this by getting the raw image from the camera, and only using a subset of the raw image frame, then programmatically picking a new subset for each raw image to use for the next frame. Needless to say, this is a large amount of work and should only be undertaken if you know what you are doing or want to have the most impressive video/picture taking app.
The iPhone 6+ has this built into the hardware and is, I believe, what the previous comment link to avfoundation is talking about.
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I need to take one picture from rear camera and another from back camera. I read that it wouldn´t possible at same time, but, you know if it is possible to switch between cameras in thi minimum time and try to take one fron and one back picture?
EDIT:
As I said before, I want to capture from both cameras at the same time. I know that it is not possible on Iphone devices but i tried to switch cameras very quickly. Iphone waste a lot of time switching between cameras. The ideal is to show in preview back camera and record frames from it, and record frames in front camera at the same time without previewing it and do not lose the front preview.
Thanks in advance.
The iPhone 7 plus and 8 plus (and X) have an effect in the native camera app called "Portrait mode", which simulates a bokeh-like effect by using depth data to blur the background.
I want to add the capability to take photos with this effect in my own app.
I can see that in iOS 11, depth data is available. But I have no idea how to use this to achieve the effect.
Am I missing something -- is it possible to turn on this effect somewhere and just get the image with it applied, rather than having to try and make this complicated algorithm myself?
cheers
Unfortunately portrait mode and portrait lighting aren't open to developers as of iOS 11 so you would have to implement a similar effect on your own. Capturing Depth in iPhone Photography and Image Editing with Depth from this years WWDC go into detail on how to capture and edit images with depth data.
There are two sample projects on the developer site that show you how to capture and visualize depth data using a Metal shader, and on how to detect faces using AVFoundation. You could definitely use these to get you started! If you search for AVCam in the Guides and Sample Code they should be the first two that come up (I would post the links but stack overflow is only letting me add two).
How to capture photo automatically in android phone? is about how to take a picture automatically without people's interaction. This feature is needed in many applications. For example, when you are going to take a picture of a document, you expect that the camera can take it automatically when the full document is insider the picture (or four corners of the document). So my question is how about doing it in iPhone or iPad?
Recently, I am working on Cordova, and does someone know that there are some plugins that have already existed for this kind of camera operations? Thanks
EDIT:
This operation will be done in an APP that will be given the full access of the camera, and the task is how to develop such an APP.
Instead of capturing photo, you should capture video frames. When the captured frame satisfies your requirements, stop capturing the video and proceed.
I am currently working on an iOS app that can take a picture programmatically using AVFoundation libraries like AVCaptureDevice through a custom button.
The new requirement is that the camera should automatically take a picture when the camera session detects something specific. For example, if the camera is open, and I line up an apple to fill a certain circle part of the capture screen, it should take the picture automatically. We can see this auto capture feature in some banking apps when you submit a mobile check deposit.
Does anyone know of existing libraries(open-source or proprietary) that can analyze images in real time while a user is taking a picture?
The first thing you are going to need to do is decide how you want to detect the apple. You can do this using shape detection, image recognition, or various other methods. This is important because you need to know the approach you want to take before you can identify the best way to implement it.
Once you know how you are going to identify the apple, the easiest way to do real-time image processing like this would be to use an existing augmented reality SDK. For example:
http://www.wikitude.com/products/wikitude-sdk/
http://artoolkit.org/
https://developer.vuforia.com/
If you are feeling really adventurous you could roll your own using AForge or a similar library. I have taken this approach in the past for basic shape detection projects.
Edit
The reason I suggest using an existing AR SDK is because generally they provide a lot of the glue between the camera feed and their API for you and it takes a lot of leg work out of the equation. Even though you won't be using any of the actual "augmentation" part of their SDKs, you can still take advantage of the detection part.
No matter what approach you take, you can think about it in the simplest terms of looking a picture, and figuring out if the item you want is in that picture. How do you decide? In most cases you look for a specific shape or pattern.
The application currently I am using has a main functionality to scan QR/Bar codes continuously using Zxing library (http://code.google.com/p/zxing/). For continuous frame capturing I used to initialize the AVCaptureSession and AVCaptureVideoOutput, AVCaptureVideoPreviewLayer described in the apple Q&A http://developer.apple.com/iphone/library/qa/qa2010/qa1702.html.
My problem is, when I used to run the camera preview, the image I can see through the Video device is much larger (1.5x) than the image we can see through the still camera of the iPhone. Our customer needs to hold the iPhone around 5cm distance from the bar code when he is scanning, but if you hold the iPhone to that parameter, the whole QR code won't be visible and the decoding fails.
Why is Video camera in iPhone 4 enlarges the image (by seeing through the AVCaptureVideoPreviewLayer) ?.
This is a function of the AVCaptureSession video preset, accessible by using the .sessionPreset property. For example, after configuring your captureSession, but before starting it, you would add
captureSession.sessionPreset = AVCaptureSessionPresetPhoto;
See the documentation here:
iOS Reference Document
The default preset for video is 1280x720 (I think) which is a lower resolution than the max supported by the camera. By using the "Photo" preset, you're getting the raw camera data.
You see the same behaviour with the built-in iPhone Camera app. Switch between still and video capture modes and you'll notice that the default zoom level changes. You see a wider view in still mode, whereas video mode zooms in a bit.
My guess is that continuous video capture needs to use a smaller area of the camera sensor to work optimally. If it used the whole sensor perhaps the system couldn't sustain 30 fps. Using a smaller area of the sensor gives the effect of "zooming in" to the scene.
I am answering my own question again. This was not answered even in Apple Dev forum, therefore I directly filed a technical support request from Apple and they have replied that this is a known issue and will be fixed and released with a future version. So there is nothing we can do more than waiting and see.