com.google.zxing

Class MultiFormatReader

java.lang.Object

com.google.zxing.MultiFormatReader

All Implemented Interfaces:

Reader

public final class MultiFormatReader
extends Object
implements Reader

MultiFormatReader is a convenience class and the main entry point into the library for most uses. By default it attempts to decode all barcode formats that the library supports. Optionally, you can provide a hints object to request different behavior, for example only decoding QR codes.

Author:

Sean Owen, dswitkin@google.com (Daniel Switkin)

Constructor Summary

Constructors

Constructor and Description
MultiFormatReader()

Method Summary

Modifier and Type	Method and Description
Result	decode(BinaryBitmap image) This version of decode honors the intent of Reader.decode(BinaryBitmap) in that it passes null as a hint to the decoders.
Result	decode(BinaryBitmap image, Map<DecodeHintType,?> hints) Decode an image using the hints provided.
Result	decodeWithState(BinaryBitmap image) Decode an image using the state set up by calling setHints() previously.
void	reset() Resets any internal state the implementation has after a decode, to prepare it for reuse.
void	setHints(Map<DecodeHintType,?> hints) This method adds state to the MultiFormatReader.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MultiFormatReader

public MultiFormatReader()

Method Detail

decode

public Result decode(BinaryBitmap image)
              throws NotFoundException

This version of decode honors the intent of Reader.decode(BinaryBitmap) in that it passes null as a hint to the decoders. However, that makes it inefficient to call repeatedly. Use setHints() followed by decodeWithState() for continuous scan applications.

Specified by:

decode in interface Reader

Parameters:

image - The pixel data to decode

Returns:

The contents of the image

Throws:

NotFoundException - Any errors which occurred

decode

public Result decode(BinaryBitmap image,
                     Map<DecodeHintType,?> hints)
              throws NotFoundException

Decode an image using the hints provided. Does not honor existing state.

Specified by:

decode in interface Reader

Parameters:

image - The pixel data to decode

hints - The hints to use, clearing the previous state.

Returns:

The contents of the image

Throws:

NotFoundException - Any errors which occurred

decodeWithState

public Result decodeWithState(BinaryBitmap image)
                       throws NotFoundException

Decode an image using the state set up by calling setHints() previously. Continuous scan clients will get a large speed increase by using this instead of decode().

Parameters:

image - The pixel data to decode

Returns:

The contents of the image

Throws:

NotFoundException - Any errors which occurred

setHints

public void setHints(Map<DecodeHintType,?> hints)

This method adds state to the MultiFormatReader. By setting the hints once, subsequent calls to decodeWithState(image) can reuse the same set of readers without reallocating memory. This is important for performance in continuous scan clients.

Parameters:

hints - The set of hints to use for subsequent calls to decode(image)

reset

public void reset()

Description copied from interface: Reader

Resets any internal state the implementation has after a decode, to prepare it for reuse.

Specified by:

reset in interface Reader