I am using the barcodereader sample application provided in the cascades samples to embed a QRCode scanner into my application.
As it stands the sample is great, but I want the scanner to open as soon as the user navigates to my screen and I want to get rid of the opening slider images that are in the sample.
Firstly, I have tried removing the images and their animations and adding the action:
onCreationCompleted: {
camera.open()
}
to the Page. This opens the camera perfectly as expected, but for some reason, the bacrode just doesn't scan.
So, I wound back a step, and this time I just put the code in exactly as is and just changed the code to read:
onCreationCompleted: {
startupAnimation.play()
}
As expected, the screen open, plays the annimation, but still it fails to read barcodes, however, if I invoke the animation again (by tapping the screen), the animation plays again and the scanner reads the barcode without any issues at all.
All I can think of is that this is a timing issue and that I need some sort of delay after the screen has been created before the camera can be started as a barcode reader?
Anyone able to help?
Thanks,
Douglas
To get scanning right away at application launch, you need to make sure the camera is actually set up and initialized.
Basically, in onCreationComplete, open the camera. In onCameraOpened, start the viewfinder. In onViewfinderStarted, set the barcode detector camera to be the camera.
Related
I recording video using MediaRecorder.When using back-camera,it working fine,but when using front camera,the video captured is being flipped/inverse.Means that the item in right,will appear on the left.The camera preview is working fine,just final captured video flipped.
Here is the camera preview looks like
But the final video appear like this(all the item in left hand side,appear on right hand side)
What I tried so far:
I tried to apply the matrix when prepare recorder,but it seems does change anything.
private boolean prepareRecorder(int cameraId){
//# Create a new instance of MediaRecorder
mRecorder = new MediaRecorder();
setCameraDisplayOrientation(this,cameraId,mCamera);
int angle = getVideoOrientationAngle(this,cameraId);
mRecorder.setOrientationHint(angle);
if(cameraId == Camera.CameraInfo.CAMERA_FACING_FRONT){
Matrix matrix = new Matrix();
matrix.preScale(1.0f,-1.0f);
}
//all other code to prepare recorder here
}
I already read for all this question below,but all this seems didnt solve my problem.For information,I using SurfaceView for the camera preview,so this question here doesn't help.
1) Android flip front camera mirror flipped video
2) How to keep android from inverting the image from the front facing camera?
3) Prevent flipping of the front facing camera
So my question is :
1) How to capture a video by front camera which the video not being inverse(exactly the same with camera preview)?
2) How to achieve this when the Camera preview is using SurfaceView but not TextureView ? (cause all the question I mention above,tell about using TextureView)
All possible solution is mostly welcome..Tq
EDIT
I made 2 short video clip to clarify the problem,please download and take a look
1) The video during camera preview of recording
2) The video of the final product of recording
So, if the system camera app produces video similar to your app, you didn't do something wrong. Now it's time to understand what happens to front-facing camera video recording.
The front facing camera is not different from the rear facing camera in the way it captures still pictures or video. There is a difference how the phone displays camera preview on the screen. To make it look more natural to the user, Android (and all other systems) mirrors the preview, so that you can see yourself as if in a mirror.
It is important to understand that this only applies to the way the preview is presented to you. If you pick up any video conferencing app, connect two devices that you hold in two hands, and look at yourself, you will see to your surprise that the two instances of yourself are flipped.
This is not a bug, this is the natural way to present the video to the other party.
See the sketch:
This is how you see the scene:
This is how your peer sees the same scene
Normally, recording of a video is done from the point if view of your peer, as in the second picture. This is the natural setup for, e.g., video conferencing.
But Snapchat and some other social apps choose to store the front-facing video clip as if you record it from the mirror (as if the recorder is in your hand on the first picture). Some people like this feature, others hate it (see https://forums.androidcentral.com/general-help-how/664539-front-camera-pics-mirrored-reversed-only-snapchat.html and https://www.reddit.com/r/nexus6/comments/3846ay/has_anyone_found_a_fix_for_snapchat_flipping)
You cannot use MediaRecorder for that. You can use the lower-level API of MediaCodec to record processed frames. You need to flip each frame 'manually', and this may be a significant performance hit, because normally the MediaRecorder 'connects' the camera to hardware encoder in a very efficient way, without need even to copy the pixels to user memory. This answer shows how you can manipulate the way camera is rendered to texture.
You can achieve this by recording video manually from surface view.
In such case preview and recording will match exactly.
I've been using this library for this purpose:
https://github.com/spaceLenny/recordablesurfaceview
Here is the guide how to use it (not with camera but with OpenGL drawing): https://withintent.uncorkedstudios.com/recording-screen-video-on-android-with-recordablesurfaceview-451c9daa213e
I followed the tutorial to create a basic video recorder using the button ("Capture" & "Stop")
Generally it works well but I noticed that if we tap too rapidly on the button to toggle between "Capture to Stop" or from "Stop to Capture", the app stop responding and crashes.
May I know the reason(s) why and how can we solve this issue?
My guess is that it takes time for the app to start the processes of Capture/Stop respectively, and by rapidly tapping the button, the respective processes are force to stop?
Also, I notice the quality of my video recorder is not as good as the default Camera App that comes with Android. (The custom video recorder seems to capture videos of darker and dimmer quality)
Can this issue be solve by adjusting the Camera parameters?
(For e.g. adjust the exposure compensation?)
So I have an application that can currently capture video with the front facing iphone camera and then do some processing on the video feed real-time. What I'm trying to do, however, is make this process run in the background and put other controls onscreen. So for example, say I'd like to run the camera and process the image feed, but I want the user to see a black screen with some buttons on it. Any ideas on how to do this?
Just so we get terminology right, by "in the background", you mean running the camera capture while your application is in the foreground, but not displaying the actual video feed. This is possible, but I wanted to make clear that if you move your whole application into the background you will not have access to the camera then.
There are a few ways to do this, but the one that I've spent the most time with is grabbing frames of video (or photos) via AV Foundation. Using an AVCaptureDevice and AVCaptureSession, you can grab the frames of video and route them to an encoder for saving to disk or for processing using your own custom code. None of this requires the camera feed to be displayed onscreen, so you can put up whatever interface you like and do this video recording or photo capture without any onscreen indication.
I would caution that you should make it explicit to your users what you are doing, so that you do not run the risk of violating someone's privacy. Apple does not react kindly to those who do this (for good reason).
I encapsulate a lot of this within my open source GPUImage video and photo processing framework, so you could look at the code for the GPUImageVideoCamera class there to see how I configure the capture inputs. I hand the video frames off to OpenGL ES for the application of filters and other processing operations, but you could ignore that portion of it if you just wanted to do your own encoding or processing.
Heres an exemple code from Apple's doc:
http://developer.apple.com/library/ios/#samplecode/PhotoPicker/Introduction/Intro.html
there is also the way to customize the camera interface.
I have lots of buttons on a web page. Depending on which one is clicked, I want to play a different video.
A large number of <video> elements doesn't seem to work particularly quickly or reliably.
So far, I have tried to:
Create and play() the video element dynamically, after an image is clicked:
var video = document.createElement('video');
video.src = 'video.mp4';
document.body.appendChild(video.play);
video.play();
This works on iOS 4, but not on iOS 3.
Create the video element before, and just change the src.
Doesn't work either.
It seems like the video object must have already done "it's thing", before it can be played.
Use window.open() to open the video URL.
This will cause an annoying new tab to open, which will remain open after playback has completed.
Set window.location
This will cause the current page to be reloaded after playback has completed, which I'm trying to avoid.
Any more ideas?
I am working an iphone app that needs to record a vedio automatically.
I used mobile coreservices framework and using that. I made it to came into video mode and clicking on record option its start capturing a vedio. But I want it automatically that is.. I should able to record a video without clicking on record option. That is when video mode comes up its automatically start record video.
Could any one help?
You can look at UIImagePickerControllers startVideoCapture method which is used to start taking video from the camera, this is to be used when you arent using the camera standard controlors and you provide and overlay view. Here is a reference UIImagePickerCOntroller ref. If this is not enough for you, you might want to look into AVFoundation framework which gives you a lot more control over video capturing process...hope that helps