Class ByteLookupTable

java.lang.Object

java.awt.image.LookupTable

java.awt.image.ByteLookupTable

public class ByteLookupTable extends LookupTable

This class defines a lookup table object. The output of a lookup operation using an object of this class is interpreted as an unsigned byte quantity. The lookup table contains byte data arrays for one or more bands (or components) of an image, and it contains an offset which will be subtracted from the input values before indexing the arrays. This allows an array smaller than the native data size to be provided for a constrained input. If there is only one array in the lookup table, it will be applied to all bands.

See Also:

Constructor Summary

Constructor	Description
`ByteLookupTable(int offset, byte[] data)`	Constructs a ByteLookupTable object from an array of bytes representing a lookup table to be applied to all bands.
`ByteLookupTable(int offset, byte[][] data)`	Constructs a ByteLookupTable object from an array of byte arrays representing a lookup table for each band.

Method Summary

Modifier and Type	Method	Description
`final byte[][]`	`getTable()`	Returns the lookup table data by reference.
`byte[]`	`lookupPixel(byte[] src, byte[] dst)`	Returns an array of samples of a pixel, translated with the lookup table.
`int[]`	`lookupPixel(int[] src, int[] dst)`	Returns an array of samples of a pixel, translated with the lookup table.

Methods declared in class LookupTable

getNumComponents, getOffset

Modifier and Type	Method	Description
`int`	`getNumComponents()`	Returns the number of components in the lookup table.
`int`	`getOffset()`	Returns the offset.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

ByteLookupTable

public ByteLookupTable(int offset, byte[][] data)

Constructs a ByteLookupTable object from an array of byte arrays representing a lookup table for each band. The offset will be subtracted from input values before indexing into the arrays. The number of bands is the length of the data argument. The data array for each band is stored as a reference.

Parameters:: offset - the value subtracted from the input values before indexing into the arrays; data - an array of byte arrays representing a lookup table for each band
Throws:: IllegalArgumentException - if offset is is less than 0 or if the length of data is less than 1

ByteLookupTable

public ByteLookupTable(int offset, byte[] data)

Constructs a ByteLookupTable object from an array of bytes representing a lookup table to be applied to all bands. The offset will be subtracted from input values before indexing into the array. The data array is stored as a reference.

Parameters:: offset - the value subtracted from the input values before indexing into the array; data - an array of bytes
Throws:: IllegalArgumentException - if offset is is less than 0 or if the length of data is less than 1

Method Details

getTable

public final byte[][] getTable()

Returns the lookup table data by reference. If this ByteLookupTable was constructed using a single byte array, the length of the returned array is one.

Returns:: the data array of this ByteLookupTable.

lookupPixel

public int[] lookupPixel(int[] src, int[] dst)

Returns an array of samples of a pixel, translated with the lookup table. The source and destination array can be the same array. Array dst is returned.

Specified by:: lookupPixel in class LookupTable
Parameters:: src - the source array.; dst - the destination array. This array must be at least as long as src. If dst is null, a new array will be allocated having the same length as src.
Returns:: the array dst, an int array of samples.
Throws:: ArrayIndexOutOfBoundsException - if src is longer than dst or if for any element i of src, src[i]-offset is either less than zero or greater than or equal to the length of the lookup table for any band.

lookupPixel

public byte[] lookupPixel(byte[] src, byte[] dst)

Returns an array of samples of a pixel, translated with the lookup table. The source and destination array can be the same array. Array dst is returned.

Parameters:: src - the source array.; dst - the destination array. This array must be at least as long as src. If dst is null, a new array will be allocated having the same length as src.
Returns:: the array dst, an int array of samples.
Throws:: ArrayIndexOutOfBoundsException - if src is longer than dst or if for any element i of src, (src[i]&0xff)-offset is either less than zero or greater than or equal to the length of the lookup table for any band.

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