Class ByteLookupTable
java.lang.Object
java.awt.image.LookupTable
java.awt.image.ByteLookupTable
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:
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Constructor Summary
ConstructorDescriptionByteLookupTable
(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 TypeMethodDescriptionfinal 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 java.awt.image.LookupTable
getNumComponents, getOffset
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Constructor Details
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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 arraysdata
- an array of byte arrays representing a lookup table for each band- Throws:
IllegalArgumentException
- ifoffset
is is less than 0 or if the length ofdata
is less than 1
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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 arraydata
- an array of bytes- Throws:
IllegalArgumentException
- ifoffset
is is less than 0 or if the length ofdata
is less than 1
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Method Details
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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
.
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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. Arraydst
is returned.- Specified by:
lookupPixel
in classLookupTable
- Parameters:
src
- the source array.dst
- the destination array. This array must be at least as long assrc
. Ifdst
isnull
, a new array will be allocated having the same length assrc
.- Returns:
- the array
dst
, anint
array of samples. - Throws:
ArrayIndexOutOfBoundsException
- ifsrc
is longer thandst
or if for any elementi
ofsrc
,src[i]-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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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. Arraydst
is returned.- Parameters:
src
- the source array.dst
- the destination array. This array must be at least as long assrc
. Ifdst
isnull
, a new array will be allocated having the same length assrc
.- Returns:
- the array
dst
, anint
array of samples. - Throws:
ArrayIndexOutOfBoundsException
- ifsrc
is longer thandst
or if for any elementi
ofsrc
,(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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