com.itextpdf.text.pdf
Class CFFFontSubset

java.lang.Object
  extended by com.itextpdf.text.pdf.CFFFont
      extended by com.itextpdf.text.pdf.CFFFontSubset

public class CFFFontSubset
extends CFFFont

This Class subsets a CFF Type Font. The subset is preformed for CID fonts and NON CID fonts. The Charstring is subsetted for both types. For CID fonts only the FDArray which are used are embedded. The Lsubroutines of the FDArrays used are subsetted as well. The Subroutine subset supports both Type1 and Type2 formatting although only tested on Type2 Format. For Non CID the Lsubroutines are subsetted. On both types the Gsubroutines is subsetted. A font which was not of CID type is transformed into CID as a part of the subset process. The CID synthetic creation was written by Sivan Toledo (sivan@math.tau.ac.il)

Author:
Oren Manor (manorore@post.tau.ac.il) and Ygal Blum (blumygal@post.tau.ac.il)

Nested Class Summary
 
Nested classes/interfaces inherited from class com.itextpdf.text.pdf.CFFFont
CFFFont.DictNumberItem, CFFFont.DictOffsetItem, CFFFont.Font, CFFFont.IndexBaseItem, CFFFont.IndexMarkerItem, CFFFont.IndexOffsetItem, CFFFont.Item, CFFFont.MarkerItem, CFFFont.OffsetItem, CFFFont.RangeItem, CFFFont.StringItem, CFFFont.SubrMarkerItem, CFFFont.UInt16Item, CFFFont.UInt24Item, CFFFont.UInt32Item, CFFFont.UInt8Item
 
Field Summary
 
Fields inherited from class com.itextpdf.text.pdf.CFFFont
arg_count, args, buf, fonts, gsubrIndexOffset, gsubrOffsets, key, nameIndexOffset, nameOffsets, stringIndexOffset, stringOffsets, topdictIndexOffset, topdictOffsets
 
Constructor Summary
CFFFontSubset(RandomAccessFileOrArray rf, HashMap<Integer,int[]> GlyphsUsed)
          C'tor for CFFFontSubset
 
Method Summary
protected  byte[] AssembleIndex(int[] NewOffsets, byte[] NewObjects)
          Function creates the new index, inserting the count,offsetsize,offset array and object array.
protected  void BuildFDArrayUsed(int Font)
          Function reads the FDSelect and builds the FDArrayUsed HashMap According to the glyphs used
protected  void BuildFDSubrsOffsets(int Font, int FD)
          The function finds for the FD array processed the local subr offset and its offset array.
protected  void BuildGSubrsUsed(int Font)
          Function scans the Glsubr used ArrayList to find recursive calls to Gsubrs and adds to Hashmap & ArrayList
protected  void BuildIndexHeader(int Count, int Offsize, int First)
          Function Build the header of an index
protected  void BuildNewCharString(int FontIndex)
          Function uses BuildNewIndex to create the new index of the subset charstrings
protected  byte[] BuildNewFile(int Font)
          The function builds the new output stream according to the subset process
protected  byte[] BuildNewIndex(int[] Offsets, HashMap<Integer,int[]> Used, byte OperatorForUnusedEntries)
          Function builds the new offset array, object array and assembles the index.
protected  void BuildNewLGSubrs(int Font)
          Function builds the new local & global subsrs indices.
protected  void BuildSubrUsed(int Font, int FD, int SubrOffset, int[] SubrsOffsets, HashMap<Integer,int[]> hSubr, ArrayList<Integer> lSubr)
          Function uses ReadAsubr on the glyph used to build the LSubr & Gsubr HashMap.
protected  int CalcBias(int Offset, int Font)
          Function calcs bias according to the CharString type and the count of the subrs
protected  int CalcHints(int begin, int end, int LBias, int GBias, int[] LSubrsOffsets)
          The function reads the subroutine and returns the number of the hint in it.
protected  void CopyHeader()
          Function Copies the header from the original fileto the output list
protected  int countEntireIndexRange(int indexOffset)
          Function computes the size of an index
protected  void CreateCharset(CFFFont.OffsetItem charsetRef, int nglyphs)
          Function creates new CharSet for non-CID fonts.
protected  void CreateFDArray(CFFFont.OffsetItem fdarrayRef, CFFFont.OffsetItem privateRef, int Font)
          Function creates new FDArray for non-CID fonts.
protected  void CreateFDSelect(CFFFont.OffsetItem fdselectRef, int nglyphs)
          Function creates new FDSelect for non-CID fonts.
protected  void CreateKeys(CFFFont.OffsetItem fdarrayRef, CFFFont.OffsetItem fdselectRef, CFFFont.OffsetItem charsetRef, CFFFont.OffsetItem charstringsRef)
          Function adds the keys into the TopDict
protected  void CreateNewStringIndex(int Font)
          Function takes the original string item and adds the new strings to accommodate the CID rules
protected  void EmptyStack()
          Empty the Type2 Stack
protected  void HandelStack()
          Function Checks how the current operator effects the run time stack after being run An operator may increase or decrease the stack size
protected  void PopStack()
          Pop one element from the stack
 byte[] Process(String fontName)
          The Process function extracts one font out of the CFF file and returns a subset version of the original.
protected  void PushStack()
          Add an item to the stack
protected  void ReadASubr(int begin, int end, int GBias, int LBias, HashMap<Integer,int[]> hSubr, ArrayList<Integer> lSubr, int[] LSubrsOffsets)
          The function reads a subrs (glyph info) between begin and end.
protected  void ReadCommand()
          The function reads the next command after the file pointer is set
protected  void ReadFDArray(int Font)
          Read the FDArray count, offsize and Offset array
protected  void readFDSelect(int Font)
          Read the FDSelect of the font and compute the array and its length
protected  int StackOpp()
          Function checks the key and return the change to the stack after the operator
 
Methods inherited from class com.itextpdf.text.pdf.CFFFont
exists, getCID, getDictItem, getEntireIndexRange, getNames, getString, isCID
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

CFFFontSubset

public CFFFontSubset(RandomAccessFileOrArray rf,
                     HashMap<Integer,int[]> GlyphsUsed)
C'tor for CFFFontSubset

Parameters:
rf - - The font file
GlyphsUsed - - a HashMap that contains the glyph used in the subset
Method Detail

readFDSelect

protected void readFDSelect(int Font)
Read the FDSelect of the font and compute the array and its length

Parameters:
Font - The index of the font being processed

BuildFDArrayUsed

protected void BuildFDArrayUsed(int Font)
Function reads the FDSelect and builds the FDArrayUsed HashMap According to the glyphs used

Parameters:
Font - the Number of font being processed

ReadFDArray

protected void ReadFDArray(int Font)
Read the FDArray count, offsize and Offset array

Parameters:
Font -

Process

public byte[] Process(String fontName)
               throws IOException
The Process function extracts one font out of the CFF file and returns a subset version of the original.

Parameters:
fontName - - The name of the font to be taken out of the CFF
Returns:
The new font stream
Throws:
IOException

CalcBias

protected int CalcBias(int Offset,
                       int Font)
Function calcs bias according to the CharString type and the count of the subrs

Parameters:
Offset - The offset to the relevant subrs index
Font - the font
Returns:
The calculated Bias

BuildNewCharString

protected void BuildNewCharString(int FontIndex)
                           throws IOException
Function uses BuildNewIndex to create the new index of the subset charstrings

Parameters:
FontIndex - the font
Throws:
IOException

BuildNewLGSubrs

protected void BuildNewLGSubrs(int Font)
                        throws IOException
Function builds the new local & global subsrs indices. IF CID then All of the FD Array lsubrs will be subsetted.

Parameters:
Font - the font
Throws:
IOException

BuildFDSubrsOffsets

protected void BuildFDSubrsOffsets(int Font,
                                   int FD)
The function finds for the FD array processed the local subr offset and its offset array.

Parameters:
Font - the font
FD - The FDARRAY processed

BuildSubrUsed

protected void BuildSubrUsed(int Font,
                             int FD,
                             int SubrOffset,
                             int[] SubrsOffsets,
                             HashMap<Integer,int[]> hSubr,
                             ArrayList<Integer> lSubr)
Function uses ReadAsubr on the glyph used to build the LSubr & Gsubr HashMap. The HashMap (of the lsubr only) is then scanned recursively for Lsubr & Gsubrs calls.

Parameters:
Font - the font
FD - FD array processed. 0 indicates function was called by non CID font
SubrOffset - the offset to the subr index to calc the bias
SubrsOffsets - the offset array of the subr index
hSubr - HashMap of the subrs used
lSubr - ArrayList of the subrs used

BuildGSubrsUsed

protected void BuildGSubrsUsed(int Font)
Function scans the Glsubr used ArrayList to find recursive calls to Gsubrs and adds to Hashmap & ArrayList

Parameters:
Font - the font

ReadASubr

protected void ReadASubr(int begin,
                         int end,
                         int GBias,
                         int LBias,
                         HashMap<Integer,int[]> hSubr,
                         ArrayList<Integer> lSubr,
                         int[] LSubrsOffsets)
The function reads a subrs (glyph info) between begin and end. Adds calls to a Lsubr to the hSubr and lSubrs. Adds calls to a Gsubr to the hGSubr and lGSubrs.

Parameters:
begin - the start point of the subr
end - the end point of the subr
GBias - the bias of the Global Subrs
LBias - the bias of the Local Subrs
hSubr - the HashMap for the lSubrs
lSubr - the ArrayList for the lSubrs

HandelStack

protected void HandelStack()
Function Checks how the current operator effects the run time stack after being run An operator may increase or decrease the stack size


StackOpp

protected int StackOpp()
Function checks the key and return the change to the stack after the operator

Returns:
The change in the stack. 2-> flush the stack

EmptyStack

protected void EmptyStack()
Empty the Type2 Stack


PopStack

protected void PopStack()
Pop one element from the stack


PushStack

protected void PushStack()
Add an item to the stack


ReadCommand

protected void ReadCommand()
The function reads the next command after the file pointer is set


CalcHints

protected int CalcHints(int begin,
                        int end,
                        int LBias,
                        int GBias,
                        int[] LSubrsOffsets)
The function reads the subroutine and returns the number of the hint in it. If a call to another subroutine is found the function calls recursively.

Parameters:
begin - the start point of the subr
end - the end point of the subr
LBias - the bias of the Local Subrs
GBias - the bias of the Global Subrs
LSubrsOffsets - The Offsets array of the subroutines
Returns:
The number of hints in the subroutine read.

BuildNewIndex

protected byte[] BuildNewIndex(int[] Offsets,
                               HashMap<Integer,int[]> Used,
                               byte OperatorForUnusedEntries)
                        throws IOException
Function builds the new offset array, object array and assembles the index. used for creating the glyph and subrs subsetted index

Parameters:
Offsets - the offset array of the original index
Used - the hashmap of the used objects
OperatorForUnusedEntries - the operator inserted into the data stream for unused entries
Returns:
the new index subset version
Throws:
IOException

AssembleIndex

protected byte[] AssembleIndex(int[] NewOffsets,
                               byte[] NewObjects)
Function creates the new index, inserting the count,offsetsize,offset array and object array.

Parameters:
NewOffsets - the subsetted offset array
NewObjects - the subsetted object array
Returns:
the new index created

BuildNewFile

protected byte[] BuildNewFile(int Font)
The function builds the new output stream according to the subset process

Parameters:
Font - the font
Returns:
the subsetted font stream

CopyHeader

protected void CopyHeader()
Function Copies the header from the original fileto the output list


BuildIndexHeader

protected void BuildIndexHeader(int Count,
                                int Offsize,
                                int First)
Function Build the header of an index

Parameters:
Count - the count field of the index
Offsize - the offsize field of the index
First - the first offset of the index

CreateKeys

protected void CreateKeys(CFFFont.OffsetItem fdarrayRef,
                          CFFFont.OffsetItem fdselectRef,
                          CFFFont.OffsetItem charsetRef,
                          CFFFont.OffsetItem charstringsRef)
Function adds the keys into the TopDict

Parameters:
fdarrayRef - OffsetItem for the FDArray
fdselectRef - OffsetItem for the FDSelect
charsetRef - OffsetItem for the CharSet
charstringsRef - OffsetItem for the CharString

CreateNewStringIndex

protected void CreateNewStringIndex(int Font)
Function takes the original string item and adds the new strings to accommodate the CID rules

Parameters:
Font - the font

CreateFDSelect

protected void CreateFDSelect(CFFFont.OffsetItem fdselectRef,
                              int nglyphs)
Function creates new FDSelect for non-CID fonts. The FDSelect built uses a single range for all glyphs

Parameters:
fdselectRef - OffsetItem for the FDSelect
nglyphs - the number of glyphs in the font

CreateCharset

protected void CreateCharset(CFFFont.OffsetItem charsetRef,
                             int nglyphs)
Function creates new CharSet for non-CID fonts. The CharSet built uses a single range for all glyphs

Parameters:
charsetRef - OffsetItem for the CharSet
nglyphs - the number of glyphs in the font

CreateFDArray

protected void CreateFDArray(CFFFont.OffsetItem fdarrayRef,
                             CFFFont.OffsetItem privateRef,
                             int Font)
Function creates new FDArray for non-CID fonts. The FDArray built has only the "Private" operator that points to the font's original private dict

Parameters:
fdarrayRef - OffsetItem for the FDArray
privateRef - OffsetItem for the Private Dict
Font - the font

countEntireIndexRange

protected int countEntireIndexRange(int indexOffset)
Function computes the size of an index

Parameters:
indexOffset - The offset for the computed index
Returns:
The size of the index


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