Appareil photo Android , onPictureTaken(byte[] imgData, Appareil photo, caméra) méthode & PictureCallback jamais appelé

J'ai une caméra personnalisée app , qui permet de prévisualiser la vidéo de la caméra de sortie sur SurfaceView et les tentatives de prendre des photos , les photos doivent être seront traitées par “xzing “scanner API pour décoder tous les codes-barres dans l'image.

Mon application aperçus correctement et ne pas jeter des erreurs ou des attentes, cependant mon onPictureTaken(byte[] imgData, Appareil photo, caméra) méthode & PictureCallback ne sont jamais appelés, donc je ne suis pas en mesure d'obtenir l'image & de poursuivre la numérisation.

Ci-dessous est le code réel de l'activité qui prend soin de l'Appareil photo de la logique. Le onPictureTaken(byte[] imgData, Appareil photo, caméra) méthode & PictureCallback sont dans cette classe(ScanVinFromBarcodeActivity.java) voir le coup :

package com.ty.tyownerspoc.barcode;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.ChecksumException;
import com.google.zxing.FormatException;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.NotFoundException;
import com.google.zxing.RGBLuminanceSource; 
import com.google.zxing.Reader;
import com.google.zxing.Result;
import com.google.zxing.common.HybridBinarizer;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.pm.PackageManager;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.ImageFormat;
import android.graphics.Matrix;
import android.graphics.Point;
import android.hardware.Camera;
import android.hardware.Camera.CameraInfo;
import android.hardware.Camera.Parameters;
import android.hardware.Camera.PictureCallback;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Display;
import android.view.SurfaceView;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.TextView;
import android.widget.Toast;
import com.ty.tyownerspoc.R;
public class ScanVinFromBarcodeActivity extends Activity {
private Camera globalCamera;
private int cameraId = 0;
private TextView VINtext = null;
private View scanButton = null;
//bitmap from camera
private Bitmap bmpOfTheImageFromCamera = null;
//global flag whether a camera has been detected
private boolean isThereACamera = false;
//surfaceView for preview object
private FrameLayout frameLayoutBarcodeScanner = null;
private CameraPreview newCameraPreview = null;
private SurfaceView surfaceViewBarcodeScanner = null;
private int counter = 0; 
private volatile boolean finishedPictureTask  = false;
/*
* This method , finds FEATURE_CAMERA, opens the camera, set parameters ,
* add CameraPreview to layout, set camera surface holder, start preview
*/
private void initializeGlobalCamera() {
try {
if (!getPackageManager().hasSystemFeature(
PackageManager.FEATURE_CAMERA)) {
Toast.makeText(this, "No camera on this device",
Toast.LENGTH_LONG).show();
} else { //check for front camera ,and get the ID
cameraId = findFrontFacingCamera();
if (cameraId < 0) {
Toast.makeText(this, "No front facing camera found.",
Toast.LENGTH_LONG).show();
} else {
Log.d("ClassScanViewBarcodeActivity",
"camera was found , ID: " + cameraId);
//camera was found , set global camera flag to true
isThereACamera = true;
//OPEN
globalCamera = Camera.open(cameraId);
//pass surfaceView to CameraPreview
newCameraPreview = new CameraPreview(this, globalCamera);
//pass CameraPreview to Layout
frameLayoutBarcodeScanner.addView(newCameraPreview);
try {
globalCamera
.setPreviewDisplay(surfaceViewBarcodeScanner
.getHolder());
} catch (IOException e) {
//TODO Auto-generated catch block
e.printStackTrace();
}
//PREVIEW
globalCamera.startPreview();
Log.d("ClassScanViewBarcodeActivity",
"camera opened & previewing");
}
}//end else ,check for front camera
}//end try
catch (Exception exc) {
//in case of exception release resources & cleanup
if (globalCamera != null) {
globalCamera.stopPreview();
globalCamera.setPreviewCallback(null);
globalCamera.release();
globalCamera = null;
}
Log.d("ClassScanViewBarcodeActivity initializeGlobalCamera() exception:",
exc.getMessage());
}//end catch
}
//onCreate, instantiates layouts & surfaceView used for video preview
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_barcode_vin_scanner);
Log.d("ClassScanViewBarcodeActivity", "onCreate ");
//create surfaceView for previewing of camera image
frameLayoutBarcodeScanner = (FrameLayout) findViewById(R.id.FrameLayoutForPreview);
surfaceViewBarcodeScanner = (SurfaceView) findViewById(R.id.surfaceViewBarcodeScanner);
initializeGlobalCamera();
//create text area & scan button
VINtext = (TextView) findViewById(R.id.mytext);
scanButton = findViewById(R.id.webbutton);
//on click listener, onClick take a picture
scanButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
//if true take a picture
if (isThereACamera) {
Log.d("ClassScanViewBarcodeActivity",
"setOnClickListener() isThereACamera: "+ isThereACamera);
//set picture format to JPEG, everytime makesure JPEg callback is called 
Parameters parameters = globalCamera.getParameters();              
parameters.setPictureFormat(ImageFormat.JPEG);
globalCamera.setParameters(parameters);                         
//take pic , should call Callback 
globalCamera.takePicture(null, null, jpegCallback);
//wait 1 sec , than start preview again
Thread.sleep(1000);
//STOP
globalCamera.stopPreview();
//start previewing again onthe SurfaceView in case use wants to take another pic/scan
globalCamera.startPreview();
}
}//end try
catch (Exception exc) {
//in case of exception release resources & cleanup
if (globalCamera != null) {
globalCamera.stopPreview();
globalCamera.setPreviewCallback(null);
globalCamera.release();
globalCamera = null;
}
Log.d("ClassScanViewBarcodeActivity setOnClickListener() exceprtion:",
exc.getMessage());
}//end catch
}//end on Click
});//end OnClickListener() implementation
}//end onCreate
@Override
protected void onResume() {
Log.d("ClassScanViewBarcodeActivity, onResume() globalCamera:",
String.valueOf(globalCamera));
if (globalCamera != null) {
//START PREVIEW
globalCamera.startPreview();
} else {
initializeGlobalCamera();
}
super.onResume();
}
@Override
protected void onStop() {
if (globalCamera != null) {
globalCamera.stopPreview();
globalCamera.setPreviewCallback(null);
globalCamera.release();
globalCamera = null;
}
super.onStop();
}
//callback used by takePicture()
PictureCallback jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] imgData, Camera camera) {
BinaryBitmap bitmap = null;
try {
Log.d("ClassScanViewBarcodeActivity" ,"onPictureTaken()");
//save image to sd card 
savePicture(imgData);
//get the bitmap from camera imageData
bmpOfTheImageFromCamera = BitmapFactory.decodeByteArray(
imgData, 0, imgData.length);
if (bmpOfTheImageFromCamera != null) {
//Galaxy S3 , incorrect rotation issue rotate to correct rotation
Matrix matrix = new Matrix();
matrix.postRotate(90);
Bitmap rotatedBitmap = Bitmap.createBitmap(bmpOfTheImageFromCamera, 0, 0, bmpOfTheImageFromCamera.getWidth(), bmpOfTheImageFromCamera.getHeight(), matrix, true);
//convert bitmap to binary bitmap
bitmap = cameraBytesToBinaryBitmap(rotatedBitmap);
if (bitmap != null) {
//decode the VIN
String VIN = decodeBitmapToString(bitmap);
Log.d("***ClassScanViewBarcodeActivity ,onPictureTaken(): VIN ",
VIN);
VINtext.setText(VIN);
} else {
Log.d("ClassScanViewBarcodeActivity ,onPictureTaken(): bitmap=",String.valueOf(bitmap));
}
} else {
Log.d("ClassScanViewBarcodeActivity , onPictureTaken(): bmpOfTheImageFromCamera = ",
String.valueOf(bmpOfTheImageFromCamera));
}
}//end try
catch (Exception exc) {
exc.getMessage();
Log.d("ClassScanViewBarcodeActivity , scanButton.setOnClickListener(): exception = ",
exc.getMessage());
}
}//end onPictureTaken()
};//jpegCallback implementation
/*
* created savePicture(byte [] data) for testing 
*/
public void savePicture(byte [] data)
{
Log.d( "ScanVinFromBarcodeActivity " , "savePicture(byte [] data)");
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
String date = dateFormat.format(new Date());
String photoFile = "Picture_"+counter+"_"+ date + ".jpg";
File sdDir = Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
String filename =sdDir + File.separator + photoFile;
File pictureFile = new File(filename);
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
Toast.makeText(this, "New Image saved:" + photoFile,
Toast.LENGTH_LONG).show();
} catch (Exception error) {
Log.d( "File not saved: " , error.getMessage());
Toast.makeText(this, "Image could not be saved.",
Toast.LENGTH_LONG).show();
}
counter++;
}
private int findFrontFacingCamera() {
int cameraId = -1;
//Search for the front facing camera
int numberOfCameras = Camera.getNumberOfCameras();
for (int i = 0; i < numberOfCameras; i++) {
CameraInfo info = new CameraInfo();
Camera.getCameraInfo(i, info);
if (info.facing == CameraInfo.CAMERA_FACING_BACK) {
Log.d("ClassScanViewBarcodeActivity , findFrontFacingCamera(): ",
"Camera found");
cameraId = i;
break;
}
}
return cameraId;
}//end findFrontFacingCamera()
@Override
protected void onPause() {
if (globalCamera != null) {
globalCamera.stopPreview();
globalCamera.setPreviewCallback(null);
globalCamera.release();
globalCamera = null;
}
super.onPause();
}//end onPause()
public String decodeBitmapToString(BinaryBitmap bitmap) {
Reader reader = null;
Result result = null;
String textResult = null;
try {
reader = new MultiFormatReader();
if (bitmap != null) {
result = reader.decode(bitmap);
if (result != null) {
textResult = result.getText();
} else {
Log.d("ClassScanViewBarcodeActivity , String decodeBitmapToString (BinaryBitmap bitmap): result = ",
String.valueOf(result));
}
} else {
Log.d("ClassScanViewBarcodeActivity , String decodeBitmapToString (BinaryBitmap bitmap): bitmap = ",
String.valueOf(bitmap));
}
/*
* byte[] rawBytes = result.getRawBytes(); BarcodeFormat format =
* result.getBarcodeFormat(); ResultPoint[] points =
* result.getResultPoints();
*/
} catch (NotFoundException e) {
//TODO Auto-generated catch block
e.printStackTrace();
} catch (ChecksumException e) {
//TODO Auto-generated catch block
e.printStackTrace();
} catch (FormatException e) {
//TODO Auto-generated catch block
e.printStackTrace();
}
return textResult;
}//end decodeBitmapToString (BinaryBitmap bitmap)
public BinaryBitmap cameraBytesToBinaryBitmap(Bitmap bitmap) {
BinaryBitmap binaryBitmap = null;
if (bitmap != null) {
int[] pixels = new int[bitmap.getHeight() * bitmap.getWidth()];
bitmap.getPixels(pixels, 0, 0, bitmap.getWidth() - 1,
bitmap.getHeight() - 1, bitmap.getWidth(),
bitmap.getHeight());
RGBLuminanceSource source = new RGBLuminanceSource(
bitmap.getWidth(), bitmap.getHeight(), pixels);
HybridBinarizer bh = new HybridBinarizer(source);
binaryBitmap = new BinaryBitmap(bh);
} else {
Log.d("ClassScanViewBarcodeActivity , cameraBytesToBinaryBitmap (Bitmap bitmap): bitmap = ",
String.valueOf(bitmap));
}
return binaryBitmap;
}
@SuppressLint("NewApi")
@SuppressWarnings("deprecation")
/*
* The method getScreenOrientation() return screen orientation either
* landscape or portrait. IF width < height , than orientation = portrait,
* ELSE landscape For backwards compatibility we use to methods to detect
* the orientation. The first method is for API versions prior to 13 or
* HONEYCOMB.
*/
public int getScreenOrientation() {
int currentapiVersion = android.os.Build.VERSION.SDK_INT;
//if API version less than 13
Display getOrient = getWindowManager().getDefaultDisplay();
int orientation = Configuration.ORIENTATION_UNDEFINED;
if (currentapiVersion < android.os.Build.VERSION_CODES.HONEYCOMB) {
//Do something for API version less than HONEYCOMB
if (getOrient.getWidth() == getOrient.getHeight()) {
orientation = Configuration.ORIENTATION_SQUARE;
} else {
if (getOrient.getWidth() < getOrient.getHeight()) {
orientation = Configuration.ORIENTATION_PORTRAIT;
} else {
orientation = Configuration.ORIENTATION_LANDSCAPE;
}
}
} else {
//Do something for API version greater or equal to HONEYCOMB
Point size = new Point();
this.getWindowManager().getDefaultDisplay().getSize(size);
int width = size.x;
int height = size.y;
if (width < height) {
orientation = Configuration.ORIENTATION_PORTRAIT;
} else {
orientation = Configuration.ORIENTATION_LANDSCAPE;
}
}
return orientation;
}//end getScreenOrientation()
}//end class ScanVinFromBarcodeActivity

Aperçu de la classe utilisée pour l'affichage en direct de la caméra sur SurfaceView (CameraPreview.java):

package com.ty.tyownerspoc.barcode;
import java.io.IOException;
import java.util.List;
import android.content.Context;
import android.hardware.Camera;
import android.hardware.Camera.Size;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.ViewGroup;
import android.hardware.Camera.CameraInfo;
/** A basic Camera preview class */
public class CameraPreview extends SurfaceView implements
SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
private Context context;
public CameraPreview(Context context, Camera camera) {
super(context);
mCamera = camera;
this.context = context;
//Install a SurfaceHolder.Callback so we get notified when the
//underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
//deprecated setting, but required on Android versions prior to 3.0
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void surfaceCreated(SurfaceHolder holder) {
//The Surface has been created, now tell the camera where to draw the
//preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException e) {
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
//empty. Take care of releasing the Camera preview in your activity.
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
//If your preview can change or rotate, take care of those events here.
//Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null) {
//preview surface does not exist
return;
}
//stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e) {
//ignore: tried to stop a non-existent preview
}
Camera.Parameters p = mCamera.getParameters();
//get width & height of the SurfaceView
int SurfaceViewWidth = this.getWidth();
int SurfaceViewHeight = this.getHeight();
List<Size> sizes = p.getSupportedPreviewSizes();
Size optimalSize = getOptimalPreviewSize(sizes, SurfaceViewWidth, SurfaceViewHeight);
//set parameters
p.setPreviewSize(optimalSize.width, optimalSize.height);
/*rotate the image by 90 degrees clockwise , in order to correctly displayed the image , images seem to be -90 degrees (counter clockwise) rotated 
* I even tried setting it to  p.setRotation(0); , but still no effect.
*/
mCamera.setDisplayOrientation(90);
mCamera.setParameters(p);
//start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
} catch (Exception e) {
Log.d("CameraPreview ,  surfaceCreated() , orientation: ",
String.valueOf(e.getMessage()));
}
}//end surfaceChanged()
static Size getOptimalPreviewSize(List <Camera.Size>sizes, int w, int h) {
final double ASPECT_TOLERANCE = 0.1;
final double MAX_DOWNSIZE = 1.5;
double targetRatio = (double) w / h;
if (sizes == null) return null;
Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
//Try to find an size match aspect ratio and size
for (Camera.Size size : sizes) {
double ratio = (double) size.width / size.height;
double downsize = (double) size.width / w;
if (downsize > MAX_DOWNSIZE) {
//if the preview is a lot larger than our display surface ignore it
//reason - on some phones there is not enough heap available to show the larger preview sizes
continue;
}
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
//Cannot find the one match the aspect ratio, ignore the requirement
//keep the max_downsize requirement
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
double downsize = (double) size.width / w;
if (downsize > MAX_DOWNSIZE) {
continue;
}
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
//everything else failed, just take the closest match
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
}//end Preview class

Mise en page de la “ScanVinFromBarcodeActivity” activité (activity_barcode_vin_scanner.xml):

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:padding="20dip" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:padding="20dip"
android:text="@string/decode_label"
android:textColor="@color/mbackground1" />
<TextView
android:id="@+id/mytext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@color/mbackground2"
android:gravity="center_horizontal"
android:padding="20dip"
android:textColor="@color/mytextcolor" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:padding="20dip"
android:text="@string/continue_label"
android:textColor="@color/mytextcolor" />
<Button
android:id="@+id/webbutton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/web_button"
android:textColor="@color/mytextcolor" />
<FrameLayout
android:id="@+id/FrameLayoutForPreview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1">
<SurfaceView
android:id="@+id/surfaceViewBarcodeScanner"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</FrameLayout>
</LinearLayout>

Toute aide sera appréciée.

Grâce

Updated & working onTakePicturen method, the that works , the PictureCallback returns (stopPreview & StartPreview were moved to inside this method in its finally block).
public void onPictureTaken(byte[] imgData, Camera camera) {
BinaryBitmap bitmap;
try {
Log.d("ClassScanViewBarcodeActivity" ,"onPictureTaken()");
//save image to sd card 
savePicture(imgData);
//get the bitmap from camera imageData
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 8; 
//down sample
bmpOfTheImageFromCamera = BitmapFactory.decodeByteArray(
imgData, 0, imgData.length,options);
if (bmpOfTheImageFromCamera != null) {
Log.d("***ClassScanViewBarcodeActivity ,onPictureTaken(): bmpOfTheImageFromCamera getByteCount(): ",
String.valueOf(bmpOfTheImageFromCamera.getByteCount()));
//Galaxy S3 , incorrect rotation issue rotate to correct rotation
/*Matrix matrix = new Matrix();
matrix.postRotate(90);
Bitmap rotatedBitmap = Bitmap.createBitmap(bmpOfTheImageFromCamera, 0, 0, bmpOfTheImageFromCamera.getWidth(), bmpOfTheImageFromCamera.getHeight(), matrix, true);*/
//convert bitmap to binary bitmap
bitmap = cameraBytesToBinaryBitmap(bmpOfTheImageFromCamera);
if (bitmap != null) {
//decode the VIN
String VIN = decodeBitmapToString(bitmap);
Log.d("***ClassScanViewBarcodeActivity ,onPictureTaken(): VIN ",
VIN);
VINtext.setText(VIN);
} else {
Log.d("ClassScanViewBarcodeActivity ,onPictureTaken(): bitmap=",String.valueOf(bitmap));
}
} else {
Log.d("ClassScanViewBarcodeActivity , onPictureTaken(): bmpOfTheImageFromCamera = ",
String.valueOf(bmpOfTheImageFromCamera));
}
}//end try
catch (Exception exc) {
exc.getMessage();
Log.d("ClassScanViewBarcodeActivity , scanButton.setOnClickListener(): exception = ",
exc.getMessage());
}
finally
{
globalCamera.stopPreview();
//start previewing again onthe SurfaceView in case use wants to take another pic/scan
globalCamera.startPreview();
}
}//end onPictureTaken()
};//jpegCallback implementation

OriginalL'auteur cyber101 | 2013-10-21