com.sun.pdfview.function
public abstract class PDFFunction extends Object
PDF Functions are defined in the reference as Section 3.9.
A PDF function maps some set of m inputs into some set of n outputs. There are 4 types of functions:
The function interface contains a single method, calculate which takes an array of m floats an interprets them into an array of n floats.
PDFFunctions do not have accessible constructors. Instead, use the static getFunction() method to read a functions from a PDF Object.
Field Summary | |
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static int | TYPE_0 The known function types |
static int | TYPE_2 |
static int | TYPE_3 |
static int | TYPE_4 |
Constructor Summary | |
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protected | PDFFunction(int type) Creates a new instance of PDFFunction |
Method Summary | |
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float[] | calculate(float[] inputs)
Map from m input values to n output values.
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float[] | calculate(float[] inputs, int inputOffset, float[] outputs, int outputOffset)
Map from m input values to n output values.
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protected abstract void | doFunction(float[] inputs, int inputOffset, float[] outputs, int outputOffset)
Subclasses must implement this method to perform the actual function
on the given set of data. |
protected float | getDomain(int i)
Get a component of the domain of this function
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static PDFFunction | getFunction(PDFObject obj)
Get a PDFFunction from a PDFObject |
int | getNumInputs()
Get the number of inputs, m, required by this function
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int | getNumOutputs()
Get the number of outputs, n, returned by this function
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protected float | getRange(int i)
Get a component of the range of this function
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int | getType()
Get the type of this function
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protected abstract void | parse(PDFObject obj) Read the function information from a PDF Object |
protected void | setDomain(float[] domain)
Set the domain of this function |
protected void | setRange(float[] range)
Set the range of this function |
Parameters: inputs an array of >= m input values
Returns: the array of n output values
Parameters: inputs an array of >= m input values inputOffset the offset into the input array to read from outputs an array of size >= n which will be filled with the output values outputOffset the offset into the output array to write to
Returns: the array of n output values
Parameters: inputs guaranteed to be at least as big as
getNumInputs()
and all values within range inputOffset the offset into the inputs array to read from outputs guaranteed to be at least as big as
getNumOutputs()
, but not yet clipped to domain outputOffset the offset into the output array to write to
Parameters: i the index into the domain array, which has size 2 * m. the ith entry in the array has index 2i, 2i + 1
Returns: the ith entry in the domain array
Returns: the number of input values expected by this function
Returns: the number of output values this function will return
Parameters: i the index into the range array, which has size 2 * n. the ith entry in the array has index 2i, 2i + 1
Returns: the ith entry in the range array
Returns: one of the types of function (0-4)