Develop Reference

Print a bitmap image without resizing through Wi-Fi on Android App?

I need to make an app for label printing like this
I am checking this tutorial
And PrintHelper has very simple and limited features.
I can only use two scales - SCALE_MODE_FILL, SCALE_MODE_FIT.
My bitmap image has a size of 512px X 512px. And I might need to adjust the size because of the label sticker size.
OR I need to choose the size of paper(ex. 100mm X 100mm) then, both way above will have the same result.
When I try this code, It opens print setting activity.
private void doPhotoPrint(Bitmap bitmap) {
PrintHelper printHelper = new PrintHelper(this);
printHelper.setColorMode(COLOR_MODE_MONOCHROME);
// Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.droids);
printHelper.printBitmap("droids.jpg - test print", bitmap);
}
However, I just want to implement the print function without opening the setting screen, But just when I click 'print' on my application, then right away print one or more bitmap images continuously with the default settings that I set(image size, black&white/color, printer that is connected, paper size).
Is there any way to make a function like the video above?

With the PrintHelper you get the system print dialog there is no way to print silently as the user has to pick the printer and the print attributes from the dialog. To function like the video, you'd need to implement the discovery and printing functionalities with the printer directly

Mobile - Scan text from camera, without taking a picture

Is there a known API or way to SCAN the text from a card without actually manually saving (and uploading) the picture? (iOS and Android)
Then I would need to know if that API can determine the marquee within the camera that should be scanned.
I want a behaviour similar to the one of QR scanners, or Augmented Reality apps. Where the user just directs the camera and the action occurs.
I have printed cards with a Redeem code in Text, and including QR will need to change the current card production.
The text is inside a white box, which may make it easier to recognise:

On iOS, you would use CIDetector with an AVCaptureSession. It can be used to process capture session output buffers as they come in from the camera without having to take a picture and provide text scanning.
For text detection, using CIDetector with CIDetectorTypeText will return areas that are likely to have text in them, but you would have to perform additional processing for Optical Character Recognition.
You could also use OpenCV for a not out of the box solution.

You can try this: https://github.com/gali8/Tesseract-OCR-iOS
Usage:
// Specify the image Tesseract should recognize on
tesseract.image = [[UIImage imageNamed:#"image_sample.jpg"] g8_blackAndWhite];
// Optional: Limit the area of the image Tesseract should recognize on to a rectangle
tesseract.rect = CGRectMake(20, 20, 100, 100);
// Optional: Limit recognition time with a few seconds
tesseract.maximumRecognitionTime = 2.0;
// Start the recognition
[tesseract recognize];

How to get pixel data from screencap.cpp directly

I'm a newbie in Android.
I using Nexus7 reference device and I've downloaded the full source code from source.android.com.
I have an engineering system image and I can make a system application.
/system/bin/screencap utility is good for me to capture screen.
I want to get a pixel data using screencap.cpp directly in my application.
When I used to screencap utility, the process is like below.
capture screen and save an image.
Open image file
decodefile to bitmap
get pixel data(int array) from bitmap
I want to remove the step 1, 2 and 3.
Just call api to get pixel data of a screen directly,
How can I do that?

If you're running with system privileges, you can just ask SurfaceComposerClient for the pixel data rather than launching a separate process to do it for you.
Looking at the screencap source code, all you really need is the Binder initialization:
ProcessState::self()->startThreadPool();
and the SurfaceComposerClient IPC call:
ScreenshotClient screenshot;
sp<IBinder> display = SurfaceComposerClient::getBuiltInDisplay(displayId);
if (display != NULL && screenshot.update(display, Rect(), false) == NO_ERROR) {
base = screenshot.getPixels();
w = screenshot.getWidth();
h = screenshot.getHeight();
s = screenshot.getStride();
f = screenshot.getFormat();
size = screenshot.getSize();
}
You can safely ignore all the /dev/graphics/fb0 stuff below it -- it's an older approach that no longer works. The rest of the code is just needed for the PNG compression.
If you're not running with system privileges, you can't capture the entire screen. You can capture your app though.

If you are writing a Java app just call /system/bin/screencap from your application (using java.lang.Process) and read the result into memory as a binary stream. You can see the binary structure in screencap.cpp, but it's just width, height, and format as four byte integers followed by the data.
Note to other readers: this is only be possible if you are a system app.

1) You can transfer data from your screencap utility to your App over the network by using sockets.
2) Android NDK can be used for direct function calls of your utility from your App.

Programmatically take a screenshot from service

it is easy to this code
Bitmap bitmap;
View v1 = MyView.getRootView();
v1.setDrawingCacheEnabled(true);
bitmap = Bitmap.createBitmap(v1.getDrawingCache());
v1.setDrawingCacheEnabled(false);
and it works great , but this is the case if there is activity.
How can I take a screenshot from service ?
my goal to take a screenshot ones in a hour ,e.i to to take screen shut every hour for example in 12 then in 1 then in 2 .... and so on

To capture ScreenShot for your activity you have to need a View of your activity, and which one is not present in your service so you have to make a TimerTask which will call your activity at every hour and your activity responding it to with current appear view and you can capture the ScreenShot from that. (I think this one is only solution for your problem.)
Or If you want to take a ScreenShot of your current device screen (any application) then you have to root permission, and read framebuffer for that which will give raw data of current screen then convert it to bitmap or any picture file you can do it in your service.

Android Screenshot Library (ASL) provides means for taking snapshots of phone's screen without the need for signing your application or having privileged (root) access to the Android system
Click here for ASL

Android Camera.takePicture - Possible to disable shutter sound and preview surface?

I am working on an app that will allow a user to take quick click and forget snapshots. Most of the app is done except for the camera working that way I would like. Right now I have the camera working but I can't seem to find a way to disable the shutter sound and I cant find a way to disable displaying the preview. I was able to cover the preview up with a control but I would rather just not have it displayed if possible.
To sum things up, these are the items that I would like to disable while utilizing the built in Camera controls.
Shutter sound
Camera screen display
Image preview onPictureTaken
Does anyone know of a resource that could point me in the right direction, I would greatly appreciate it. I have been following CommonsWare's example from this sample fairly closely.
Thank you.

This is actually a property in the build.prop of a phone. I'm unsure if its possible to change this. Unless you completely override it and use your own camera code. Using what you can that is available in the SDK.
Take a look at this:
CameraService.cpp
. . .
CameraService::Client::Client(const sp<CameraService>& cameraService,
const sp<ICameraClient>& cameraClient,
const sp<CameraHardwareInterface>& hardware,
int cameraId, int cameraFacing, int clientPid) {
mPreviewCallbackFlag = FRAME_CALLBACK_FLAG_NOOP;
mOrientation = getOrientation(0, mCameraFacing == CAMERA_FACING_FRONT);
mOrientationChanged = false;
cameraService->setCameraBusy(cameraId);
cameraService->loadSound();
LOG1("Client::Client X (pid %d)", callingPid)
}
void CameraService::loadSound() {
Mutex::Autolock lock(mSoundLock);
LOG1("CameraService::loadSound ref=%d", mSoundRef);
if (mSoundRef++) return;
mSoundPlayer[SOUND_SHUTTER] = newMediaPlayer("/system/media/audio/ui/camera_click.ogg");
mSoundPlayer[SOUND_RECORDING] = newMediaPlayer("/system/media/audio/ui/VideoRecord.ogg");
}
As can be noted, the click sound is started without your interaction.
This is the service used in the Gingerbread Source code.
The reason they DON'T allow this is because it is illegal is some countries. Only way to achieve what you want is to have a custom ROM.
Update
If what being said here: http://androidforums.com/t-mobile-g1/6371-camera-shutter-sound-effect-off.html
still applies, then you could write a timer that turns off the sound (Silent Mode) for a couple of seconds and then turn it back on each time you take a picture.

You may use the data from the preview callback using a function to save it at a picture on some type of trigger such as a button, using onclick listener. you could compress the image to jpeg or png. In this way, there no shutterCallback to be implemented. and therefore you can play any sound you want or none when taking a picture.

You can effectively hide the preview surface by giving it dimensions of 1p in the xml file (I found an example the said 0p but for some reason that was giving me errors).
It may be illegal to have a silent shutter in some places, but it doesn't appear that the US is such a place, as my HTC One gives me an option to silence it, and in fact, since Android 4.2 you can do this:
Camera.CameraInfo info=new Camera.CameraInfo();
if (info.canDisableShutterSound) {
camera.enableShutterSound(false);
}