Decode Methods
Method | Description |
---|---|
decodeBuffer(ImageData) |
Decode barcodes with an image data object. This method can handle the orientation information and output a result with transformation matrix for transferring coordinates. |
decodeBuffer |
Decode barcodes with image data including pixel buffer, width, height, stride and pixel format. Generally, this method is used when processing video streaming. |
decodeFile |
Decode barcodes from a specified image file. |
decodeFileInMemory(fileBytes) |
Decode barcodes from an image file in memory. |
decodeFileInMemory(fileStream) |
Decode barcodes from an image file in memory. |
decodeBase64String |
Decode barcodes from a base64 encoded string. |
decodeBufferedImage |
Decodes barcode from a buffered imag (bitmap). |
decodeBuffer(ImageData)
Decode barcodes from an ImageData
object. The ImageData
object stores the pixel buffer, width, height, stride and pixel format of the image.
TextResult[] decodeBuffer(ImageData imageData) throws BarcodeReaderException
Parameters
imageData
: The image data in memory buffer which also contains the pixel format and orientation information.
Exceptions
A BarcodeReaderException
is thrown when:
- The library failed to read the image.
- The image data type is not supported.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
There are several approaches for you to get an ImageData.
Get ImageData from DCEFrame
You can import CameraEnhancer to acquire buffered video frames from frameOutputCallback
or videoBuffer
of DCE.
Code Snippet
/*You can get frames from frame output call back if you import dynamsoft camera enhancer package.*/
/*You can get all the required parameters of decodeBuffer from DCEFrame.*/
import com.dynamsoft.dce.CameraEnhancer;
BarcodeReader reader = new BarcodeReader();
mCameraEnhancer.addListener(new DCEFrameListener() {
@Override
public void frameOutputCallback(DCEFrame dceFrame, long l) {
ImageData data = new ImageData();
data.bytes = dceFrame.getImageData();
data.width = dceFrame.getWidth();
data.height = dceFrame.getHeight();
data.stride = dceFrame.getStrides()[0];
data.format = dceFrame.getPixelFormat();
data.orientation = dceFrame.getOrientation();
}
});
Get ImageData from Android Camera2
When you are using Android Camera2, you can create ImageData
from android.media.ImageReader
.
Code Snippet
previewReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener() {
@Override
public void onImageAvailable(ImageReader reader) {
Image mImage = reader.acquireLatestImage();
ByteBuffer bufferY = mImage.getPlanes()[0].getBuffer();
int strideY = mImage.getPlanes()[0].getRowStride() / mImage.getPlanes()[0].getPixelStride();
ByteBuffer bufferU = mImage.getPlanes()[1].getBuffer();
int strideU = mImage.getPlanes()[1].getRowStride() / mImage.getPlanes()[1].getPixelStride();
ByteBuffer bufferV = mImage.getPlanes()[2].getBuffer();
int strideV = mImage.getPlanes()[2].getRowStride() / mImage.getPlanes()[2].getPixelStride();
int padingY = mImage.getPlanes()[0].getRowStride() - mImage.getWidth();
int padingU = mImage.getPlanes()[1].getRowStride() - mImage.getWidth();
byte[] newData = new byte[bufferY.limit()];
newData = new byte[bufferY.limit() + bufferU.limit() + 1 + padingY + padingU];
bufferV.get(newData, bufferY.limit() + padingY, 1);
bufferU.get(newData, bufferY.limit() + padingY + 1, bufferU.limit());
bufferY.get(newData, 0, bufferY.limit());
int[] strides = new int[]{strideY, strideU, strideV};
ImageData data = new ImageData();
data.bytes = dceFrame.getImageData();
data.width = strideY;
data.height = mImage.getHeight();
data.stride = strideY;
data.format = 3;
data.orientation = 0;
}
},handler);
Get ImageData from CameraX
When you are using CameraX, you can create ImageData
from androidx.camera.core.ImageProxy
.
Code Snippet
private final ImageAnalysis.Analyzer mBarcodeAnalyzer = new ImageAnalysis.Analyzer() {
@Override
public void analyze(@NonNull ImageProxy imageProxy) {
try {
// insert your code here.
// after done, release the ImageProxy object
if (isShowingDialog) {
mImageData = null;
return;
}
byte[] data = new byte[imageProxy.getPlanes()[0].getBuffer().remaining()];
imageProxy.getPlanes()[0].getBuffer().get(data);
int nRowStride = imageProxy.getPlanes()[0].getRowStride();
int nPixelStride = imageProxy.getPlanes()[0].getPixelStride();
ImageData imageData = new ImageData();
imageData.bytes = data;
imageData.width = imageProxy.getWidth();
imageData.height = imageProxy.getHeight();
imageData.stride = nRowStride;
imageData.format = EnumImagePixelFormat.IPF_NV21;
imageData.orientation = imageProxy.getImageInfo().getRotationDegrees();
} finally {
imageProxy.close();
}
}
};
decodeBuffer
Decode barcodes with image data including pixel buffer, width, height, stride and pixel format.
TextResult[] decodeBuffer(byte[] buffer, int width, int height, int stride, int enumImagePixelFormat) throws BarcodeReaderException
Parameters
buffer
: The array of bytes that stores the pixel buffer of the image.
Width
: The width of the image in pixels.
Height
: The height of the image in pixels.
Stride
: The stride is measured by the byte
length of each line in the buffer
.
format
: The image pixel format used in the image byte array.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
Exceptions
A BarcodeReaderException
is thrown when:
- The library failed to read the image.
- The image data type is not supported.
decodeFile
Decode barcodes from a specified image file.
TextResult[] decodeFile(String fileFullPath) throws BarcodeReaderException
Parameters
fileFullPath
: A string defining the file path. It supports BMP, TIFF, JPG and PNG.
Note: PDF is not supported by mobile editions. Please use server/desktop editions instead.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
Exceptions
A BarcodeReaderException
is thrown when:
- The file is not found.
- The library failed to read the image.
- The image data type is not supported.
Code Snippet
BarcodeReader reader = new BarcodeReader();
/*Init DBR license before decoding*/
/*Read external storage permission is required when decoding from a file*/
TextResult[] result = reader.decodeFile(Environment.getExternalStorageDirectory().toString()+"your file path");
decodeFileInMemory(fileBytes)
Decode barcodes from an image file in memory.
TextResult[] decodeFileInMemory(byte[] fileBytes) throws BarcodeReaderException
Parameters
fileBytes
: The image file bytes in memory.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
Exceptions
A BarcodeReaderException
is thrown when:
- The library failed to read the image.
- The image data type is not supported.
Code Snippet
BarcodeReader reader = new BarcodeReader();
/*Init DBR license before decoding
get bufferBytes from other component*/
TextResult[] result = reader.decodeFileInMemory(bufferBytes);
decodeFileInMemory(fileStream)
Decode barcodes from an image file in memory.
TextResult [] decodeFileInMemory(InputStream fileStream) throws BarcodeReaderException, IOException
Parameters
fileStream
: The image file bytes in memory.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
Exceptions
A BarcodeReaderException
is thrown when:
- The library failed to read the image.
- The image data type is not supported.
Code Snippet
BarcodeReader reader = new BarcodeReader();
/*Init DBR license before decoding
get bufferBytes from other component*/
TextResult[] result = reader.decodeFileInMemory(fileStream);
decodeBase64String
Decode barcode from an image file encoded as a base64 string.
TextResult[] decodeBase64String(String base64) throws BarcodeReaderException
Parameters
base64
: A base64 encoded string that represents an image.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
Exceptions
A BarcodeReaderException
is thrown when:
- The library failed to read the image.
- The image data type is not supported.
Code Snippet
BarcodeReader reader = new BarcodeReader();
/*Init DBR license before decoding*/
TextResult[] result = reader.decodeBase64String("file in base64 string");
decodeBufferedImage
Decodes barcode from a buffered image (bitmap).
TextResult[] decodeBufferedImage(Bitmap image) throws BarcodeReaderException
Parameters
image
: The image to be decoded.
Return Value
The TextResult
of all successfully decoded barcodes. TextResult
includes the text, format and other information about the barcodes.
Exceptions
A BarcodeReaderException
is thrown when:
- The library failed to read the image.
- The image data type is not supported.
Code Snippet
BarcodeReader reader = new BarcodeReader();
/*Init DBR license before decoding*/
/*get BufferedImage input from other component*/
TextResult[] result = reader.decodeBufferedImage(input);