Use ZXing libs to decode bitmap with a QRCode on Android - java

Recently I have a difficulty using zxing to decode bitmap. I search solutions on Internet and I have tried some of them.Here is my try:
Bitmap bitmap = BitmapFactory.decodeResource(getResources(),R.drawable.qrcode);
String result = DecodeUtils.decodeWithZxing(bitmap);
R.drawable.qrcode is a .jpg file.
And BarCodeUtil.java is:
public static String decodeWithZxing(Bitmap bitmap) {
MultiFormatReader multiFormatReader = new MultiFormatReader();
Map<DecodeHintType, Object> hints = new Hashtable<>();
hints.put(DecodeHintType.PURE_BARCODE, Boolean.TRUE);
multiFormatReader.setHints(hints);
int width = bitmap.getWidth();
int height = bitmap.getHeight();
int[] pixels = new int[width * height];
bitmap.getPixels(pixels, 0, width, 0, 0, width, height);
Result rawResult = null;
RGBLuminanceSource source = new RGBLuminanceSource(width, height, pixels);
if (source != null) {
BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(source));
try {
rawResult = multiFormatReader.decodeWithState(binaryBitmap);
} catch (ReaderException re) {
re.printStackTrace();
} finally {
multiFormatReader.reset();
}
}
return rawResult != null ? rawResult.getText() : null;
}
But when I run the above code,I got a exception:
com.google.zxing.NotFoundException
So I search the exception,someone think bitmap size causes this exception.Then I resize the bitmap size:
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = false;
options.inSampleSize = 4;
Bitmap bitmap = BitmapFactory.decodeResource(getResources(),R.drawable.zhifubao,options);
String result = DecodeUtils.decodeWithZxing(bitmap)
But it still does not work for me.
Is there a good solution to decode bitmap with a qrcode?

I know this is probably very late, but, that just means that no barcode was found in the image. See here
NotFoundException
Thrown when a barcode was not found in the image.
If anyone else ends up with the same problem, that is, cannot decode a barcode such as QRcode or upc, a possibility might be using the wrong colorspace of the bitmap. You might be attempting to use RGB when the data from the camera is actually in YUV.
Instead of RGBLuminanceSource, you should use PlanarYUVLuminanceSource as in the example here

your development tools is eclipse or android studio ?
if is android stuido:
in your project > app > build. gradel on add:
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
}
then sync gradle.

Related

SetImageUri showing no Image

I want to let a image on my phone to show up in the Imageview. But in the ANdroid Studio emulator it is working but not on my own phone.
String imgPath = getIntent().getExtras().getString("imgPath");
System.out.println(imgPath);
if(!imgPath.equals("?"))
{
File img_file = new File(imgPath);
ImageView imgView = findViewById(R.id.show_image_war);
imgView.setImageURI(Uri.fromFile(img_file));
}
The path is /storage/emulated/0/imagesWarranty/img_MyWarranty_ID1.jpg . Both on the image in my phone and the path in my code where I get the image.
It might be issue of resolution. Even I was getting error of resolution while I was displaying image from uri.
I used below code and It worked for me :
Uri imageUri = Uri.parse(imagePath);
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(new File(imageUri.getPath()).getAbsolutePath(), options);
int imageHeight = options.outHeight;
int imageWidth = options.outWidth;
if (imageHeight > 4096 || imageWidth > 4096) {
BitmapFactory.Options opts = new BitmapFactory.Options();
opts.inSampleSize = 4;
Bitmap bitmap = BitmapFactory.decodeFile(imageUri.toString(), opts);
viewHolder.imgAvatarLogoList3.setImageBitmap(bitmap);
} else {
Picasso.with(context)
.load(new File(imageUri.getPath())) // Uri of the picture
.into(viewHolder.imgAvatarLogoList3);
}
Addition to this answer [https://stackoverflow.com/a/48354307/9255006]
In that rotation bug define the image orientation for the image using ExifInterface.
Here is the code
private void SetOrientation(){
try {
ExifInterface exif=new ExifInterface(photoURI.getPath());
int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION,ExifInterface.ORIENTATION_UNDEFINED);
if (orientation == ExifInterface.ORIENTATION_ROTATE_90) { orientationInDegrees=90; }
else if (orientation == ExifInterface.ORIENTATION_ROTATE_180) { orientationInDegrees=180; }
else if (orientation == ExifInterface.ORIENTATION_ROTATE_270) { orientationInDegrees=270; }
else { orientationInDegrees=0; }
Toast.makeText(this, String.valueOf(orientationInDegrees), Toast.LENGTH_SHORT).show();
} catch (IOException e) {
e.printStackTrace();
}
}
You can then set this orientation to your image.
This happens when the image has a very high resolution that the system needs some additional milliseconds to display, and since this happens in the UI thread onDraw() of the image view will draw it as an empty.
The easiest way I found for this issue is to use the Picasso library this way:
Picasso.get().load(imgUri).fit().centerCrop()
.into(imageview);
The reason behind those two methods (fit(), centerCrop())
Is that fit make sure that the image fit the bound container and then crop the image which force the system to redraw the image but this time with the convenient resolution (because of fit and crop).

Image losing quality and size in android?

I have an app which takes photos of receipts and upload it to a remote server.
I get the full-sized photo of the image from the camera intent correctly.I followed this using the official documentation in Google developer.
I then set my picture like this.
private void setPic() {
// Get the dimensions of the View
int targetW = imageView.getWidth();
int targetH = imageView.getHeight();
// Get the dimensions of the bitmap
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
int photoW = bmOptions.outWidth;
int photoH = bmOptions.outHeight;
// Determine how much to scale down the image
int scaleFactor = Math.min(photoW/targetW, photoH/targetH);
// Decode the image file into a Bitmap sized to fill the View
bmOptions.inJustDecodeBounds = false;
bmOptions.inSampleSize = scaleFactor;
bmOptions.inPurgeable = true;
Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
//Bitmap bitmap = null;
//try
//{
//bitmap = MediaStore.Images.Media.getBitmap(getContentResolver() , //Uri.parse(mCurrentPhotoPath));
//}
//catch (Exception e)
//{
//handle exception
//}
imageView.setImageBitmap(bitmap);
new ImageSaver(getApplicationContext()).
setFileName("currentImage.png").
setDirectoryName("Android_Upload").
save(bitmap);
Model.currentImage = "currentImage.png";
}
This works fine when viewed on the device. But after its sent to the server and viewed from there, the image size is too small.
ImageSaver class pretty much saves the image elsewhere and compresses it but with 100 quality in png.I do this, so I can later the image in the database as Blob(again with 100 quality)
How can I decode the image and show the image in the image view but without losing quality (and the size?)
Apparently, you have scaled down your image while decoding.
You may want to remove the following line:
bmOptions.inSampleSize = scaleFactor;

Java android bitmap = null for certain images

I' making an android app which allows the user to take a photo and then the app will print some RGB value etc. I'm saving the pictures taken on the phone and then I make a bitmap out of those png files. I just found out that I should sleep the application for a moment in order for the image to be saved. But I'm still getting that the bitmap is null for some images I take. If I take an image of Rubik's cube with it's 6 different colors I almost never get the null pointer exception. But if I take a picture of the wall or something else the bitmap is = null.
Does anyone know what I should do in order to fix this?
Bitmap myBitmap;
final String dir =
Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) +
"/picFolder/";
try{
file = dir+Integer.toString(side)+".jpg";
File f = new File(file);
options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
myBitmap = BitmapFactory.decodeFile(file,options);
for(int i = 0; i<3; i++){
for(int j = 0; j<3; j++){
cube[side-1][i][j] = getColor(myBitmap, i, j);
}
}
}catch (Exception e){
Log.e("er0r", "HERE:::: " + e.toString());
}
I also faced the same problem when I was developing camera in my app.
For some images it was working fine and for some images it was showing null.
Later I found that is a size issue.
I fixed that issue like this,
private static Bitmap compressBitmap(Bitmap original) {
ByteArrayOutputStream out = new ByteArrayOutputStream();
original.compress(Bitmap.CompressFormat.JPEG, 100, out);
Bitmap decoded = BitmapFactory.decodeStream(new ByteArrayInputStream(out.toByteArray()));
return decoded;
}
Let me know if you need any other help.

Image from ACTION_IMAGE_CAPTURE Rotated

I am trying to simply get an image from a phone's camera. Surprisingly, it returns rotated. I've scoured the internet for fixes and came across many solutions using ExifInterface, but it only works sometimes. It gets the orientation wrong seemingly randomly, as I merely recompile and see different results. I have found some people saying this is a fault of the class itself being bugged.
I found other solutions that require like two additional libraries and more java files to do the job, but that just seems ridiculous (and I am avoiding additional packages). How come images are rotated in the first place (in storage they are perfectly fine), and how hard can it possibly be to fix the issue? Also - rotating the Image View also works (and seems much easier than literally creating a rotated image), but I need to know by how much to rotate the view.
EDIT---- I realized that the image is consistently rotated 270 degrees clockwise from the orientation the image was taken in (inside the intent) if the back camera was used, and 90 degrees if the front camera was used. Thus I only really need a way to find out this orientation.
Intent called here:
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
// Create the File where the photo should go
File photoFile = null;
try {
photoFile = setUpPhotoFile();
mCurrentPhotoPath = photoFile.getAbsolutePath();
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile));
} catch (IOException ex) {
// Error occurred while creating the File
photoFile = null;
mCurrentPhotoPath = null;
}
// Continue only if the File was successfully created
if (photoFile != null) {
startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
} else {
Toast noStorage = Toast.makeText(this, "Cannot access mounted storage.", Toast.LENGTH_SHORT);
noStorage.show();
}
}
}
Bitmap created here:
private void setPic() {
/* Get the size of the ImageView */
int targetW = mImageView.getWidth();
int targetH = mImageView.getHeight();
/* Get the size of the image */
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
int photoW = bmOptions.outWidth;
int photoH = bmOptions.outHeight;
/* Figure out which way needs to be reduced less */
int scale = 1;
if (photoH > targetH|| photoW > targetW) {
scale = Math.max(
(int)Math.pow(2, (int) Math.ceil(Math.log(targetW /
(double) photoW)) / Math.log(0.5)),
(int)Math.pow(2, (int) Math.ceil(Math.log(targetH /
(double) photoH)) / Math.log(0.5)));
;
}
/* Set bitmap options to scale the image decode target */
bmOptions.inJustDecodeBounds = false;
bmOptions.inSampleSize = scale;
/* Decode the JPEG file into a Bitmap */
Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
/*-----------How should I rotate bitmap/mImageView to correct orientation?*/
/* Associate the Bitmap to the ImageView */
mImageView.setImageBitmap(bitmap);
mImageView.setVisibility(View.VISIBLE);
}
The best solution I have found is this one:
https://www.samieltamawy.com/how-to-fix-the-camera-intent-rotated-image-in-android/
I post the link because I don't want all the credit.
Sami Eltamawy has written a function that rotate the image if its need to be rotated.
I try the code and is working on my devices that the image got rotated.

QR code scan from image file

Tried to use several libraries like ZXing, ZBar and their forks but didn't find way to scan barcode not from camera but from file.
Can someone point me to right direction? Preferably I'm looking into ZXing: how to scan image from file (not from camera).
Please.
In the end I've found solution. Code is (originated from here):
import com.google.zxing.*;
public static String scanQRImage(Bitmap bMap) {
String contents = null;
int[] intArray = new int[bMap.getWidth()*bMap.getHeight()];
//copy pixel data from the Bitmap into the 'intArray' array
bMap.getPixels(intArray, 0, bMap.getWidth(), 0, 0, bMap.getWidth(), bMap.getHeight());
LuminanceSource source = new RGBLuminanceSource(bMap.getWidth(), bMap.getHeight(), intArray);
BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
Reader reader = new MultiFormatReader();
try {
Result result = reader.decode(bitmap);
contents = result.getText();
}
catch (Exception e) {
Log.e("QrTest", "Error decoding barcode", e);
}
return contents;
}
Gradle referencing as:
dependencies {
compile 'com.google.zxing:core:3.2.1'
}
Usage:
InputStream is = new BufferedInputStream(new FileInputStream(file));
Bitmap bitmap = BitmapFactory.decodeStream(is);
String decoded=scanQRImage(bitmap);
Log.i("QrTest", "Decoded string="+decoded);

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