public class

JPEGHuffmanTable

extends Object
java.lang.Object
   ↳ javax.imageio.plugins.jpeg.JPEGHuffmanTable

Class Overview

A class encapsulating a single JPEG Huffman table. Fields are provided for the "standard" tables taken from Annex K of the JPEG specification. These are the tables used as defaults.

For more information about the operation of the standard JPEG plug-in, see the JPEG metadata format specification and usage notes

Summary

Fields
public static final JPEGHuffmanTable StdACChrominance The standard AC chrominance Huffman table.
public static final JPEGHuffmanTable StdACLuminance The standard AC luminance Huffman table.
public static final JPEGHuffmanTable StdDCChrominance The standard DC chrominance Huffman table.
public static final JPEGHuffmanTable StdDCLuminance The standard DC luminance Huffman table.
Public Constructors
JPEGHuffmanTable(short[] lengths, short[] values)
Creates a Huffman table and initializes it.
Public Methods
short[] getLengths()
Returns an array of shorts containing the number of values for each length in the Huffman table.
short[] getValues()
Returns an array of shorts containing the values arranged by increasing length of their corresponding codes.
String toString()
Returns a String representing this Huffman table.
[Expand]
Inherited Methods
From class java.lang.Object

Fields

public static final JPEGHuffmanTable StdACChrominance

The standard AC chrominance Huffman table.

public static final JPEGHuffmanTable StdACLuminance

The standard AC luminance Huffman table.

public static final JPEGHuffmanTable StdDCChrominance

The standard DC chrominance Huffman table.

public static final JPEGHuffmanTable StdDCLuminance

The standard DC luminance Huffman table.

Public Constructors

public JPEGHuffmanTable (short[] lengths, short[] values)

Creates a Huffman table and initializes it. The input arrays are copied. The arrays must describe a possible Huffman table. For example, 3 codes cannot be expressed with a single bit.

Parameters
lengths an array of shorts where lengths[k] is equal to the number of values with corresponding codes of length k + 1 bits.
values an array of shorts containing the values in order of increasing code length.
Throws
IllegalArgumentException if lengths or values are null, the length of lengths is greater than 16, the length of values is greater than 256, if any value in lengths or values is less than zero, or if the arrays do not describe a valid Huffman table.

Public Methods

public short[] getLengths ()

Returns an array of shorts containing the number of values for each length in the Huffman table. The returned array is a copy.

Returns
  • a short array where array[k-1] is equal to the number of values in the table of length k.
See Also

public short[] getValues ()

Returns an array of shorts containing the values arranged by increasing length of their corresponding codes. The interpretation of the array is dependent on the values returned from getLengths. The returned array is a copy.

Returns
  • a short array of values.
See Also

public String toString ()

Returns a String representing this Huffman table.

Returns
  • a String representing this Huffman table.