Class CFFFontSubset


  • 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)
    • Field Detail

      • SubrsFunctions

        private static final java.lang.String[] SubrsFunctions
        The Strings in this array represent Type1/Type2 operator names
      • SubrsEscapeFuncs

        private static final java.lang.String[] SubrsEscapeFuncs
        The Strings in this array represent Type1/Type2 escape operator names
      • ENDCHAR_OP

        private static final byte ENDCHAR_OP
        Operator codes for unused CharStrings and unused local and global Subrs
        See Also:
        Constant Field Values
      • GlyphsUsed

        private final java.util.HashMap GlyphsUsed
        A HashMap containing the glyphs used in the text after being converted to glyph number by the CMap
      • glyphsInList

        private final java.util.ArrayList glyphsInList
        The GlyphsUsed keys as an ArrayList
      • FDArrayUsed

        private final java.util.HashMap FDArrayUsed
        A HashMap for keeping the FDArrays being used by the font
      • hSubrsUsed

        private java.util.HashMap[] hSubrsUsed
        A HashMaps array for keeping the subroutines used in each FontDict
      • lSubrsUsed

        private java.util.ArrayList[] lSubrsUsed
        The SubroutinesUsed HashMaps as ArrayLists
      • hGSubrsUsed

        private final java.util.HashMap hGSubrsUsed
        A HashMap for keeping the Global subroutines used in the font
      • lGSubrsUsed

        private final java.util.ArrayList lGSubrsUsed
        The Global SubroutinesUsed HashMaps as ArrayLists
      • hSubrsUsedNonCID

        private final java.util.HashMap hSubrsUsedNonCID
        A HashMap for keeping the subroutines used in a non-cid font
      • lSubrsUsedNonCID

        private final java.util.ArrayList lSubrsUsedNonCID
        The SubroutinesUsed HashMap as ArrayList
      • NewLSubrsIndex

        private byte[][] NewLSubrsIndex
        An array of the new Indexes for the local Subr. One index for each FontDict
      • NewSubrsIndexNonCID

        private byte[] NewSubrsIndexNonCID
        The new subroutines index for a non-cid font
      • NewGSubrsIndex

        private byte[] NewGSubrsIndex
        The new global subroutines index of the font
      • NewCharStringsIndex

        private byte[] NewCharStringsIndex
        The new CharString of the font
      • GBias

        private int GBias
        The bias for the global subroutines
      • OutputList

        private java.util.LinkedList OutputList
        The linked list for generating the new font stream
      • NumOfHints

        private int NumOfHints
        Number of arguments to the stem operators in a subroutine calculated recursively
    • Constructor Detail

      • CFFFontSubset

        public CFFFontSubset​(RandomAccessFileOrArray rf,
                             java.util.HashMap GlyphsUsed)
        C'tor for CFFFontSubset
        Parameters:
        rf - - The font file
        GlyphsUsed - - a HashMap that contains the glyph used in the subset
    • Method Detail

      • CountCharset

        private int CountCharset​(int Offset,
                                 int NumofGlyphs)
        Calculates the length of the charset according to its format
        Parameters:
        Offset - The Charset Offset
        NumofGlyphs - Number of glyphs in the font
        Returns:
        the length of the Charset
      • CountRange

        private int CountRange​(int NumofGlyphs,
                               int Type)
        Function calculates the number of ranges in the Charset
        Parameters:
        NumofGlyphs - The number of glyphs in the font
        Type - The format of the Charset
        Returns:
        The number of ranges in the Charset data structure
      • readFDSelect

        private 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

        private 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

        private void ReadFDArray​(int Font)
        Read the FDArray count, offsize and Offset array
        Parameters:
        Font -
      • Process

        public byte[] Process​(java.lang.String fontName)
                       throws java.io.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:
        java.io.IOException
      • CalcBias

        private 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

        private void BuildNewCharString​(int FontIndex)
                                 throws java.io.IOException
        Function uses BuildNewIndex to create the new index of the subset charstrings
        Parameters:
        FontIndex - the font
        Throws:
        java.io.IOException
      • BuildNewLGSubrs

        private void BuildNewLGSubrs​(int Font)
                              throws java.io.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:
        java.io.IOException
      • BuildFDSubrsOffsets

        private 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

        private void BuildSubrUsed​(int Font,
                                   int FD,
                                   int SubrOffset,
                                   int[] SubrsOffsets,
                                   java.util.HashMap hSubr,
                                   java.util.ArrayList 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

        private 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

        private void ReadASubr​(int begin,
                               int end,
                               int GBias,
                               int LBias,
                               java.util.HashMap hSubr,
                               java.util.ArrayList 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

        private 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

        private 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

        private void EmptyStack()
        Empty the Type2 Stack
      • PopStack

        private void PopStack()
        Pop one element from the stack
      • PushStack

        private void PushStack()
        Add an item to the stack
      • ReadCommand

        private void ReadCommand()
        The function reads the next command after the file pointer is set
      • CalcHints

        private 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

        private byte[] BuildNewIndex​(int[] Offsets,
                                     java.util.HashMap Used,
                                     byte OperatorForUnusedEntries)
                              throws java.io.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:
        java.io.IOException
      • AssembleIndex

        private 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

        private 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

        private void CopyHeader()
        Function Copies the header from the original fileto the output list
      • BuildIndexHeader

        private 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

        private 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

        private 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

        private 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

        private 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

        private 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
      • Reconstruct

        private void Reconstruct​(int Font)
        Function reconstructs the FDArray, PrivateDict and LSubr for CID fonts
        Parameters:
        Font - the font
      • ReconstructFDArray

        private void ReconstructFDArray​(int Font,
                                        CFFFont.OffsetItem[] fdPrivate)
        Function subsets the FDArray and builds the new one with new offsets
        Parameters:
        Font - The font
        fdPrivate - OffsetItem Array (one for each FDArray)
      • ReconstructPrivateDict

        private void ReconstructPrivateDict​(int Font,
                                            CFFFont.OffsetItem[] fdPrivate,
                                            CFFFont.IndexBaseItem[] fdPrivateBase,
                                            CFFFont.OffsetItem[] fdSubrs)
        Function Adds the new private dicts (only for the FDs used) to the list
        Parameters:
        Font - the font
        fdPrivate - OffsetItem array one element for each private
        fdPrivateBase - IndexBaseItem array one element for each private
        fdSubrs - OffsetItem array one element for each private
      • ReconstructPrivateSubrs

        private void ReconstructPrivateSubrs​(int Font,
                                             CFFFont.IndexBaseItem[] fdPrivateBase,
                                             CFFFont.OffsetItem[] fdSubrs)
        Function Adds the new LSubrs dicts (only for the FDs used) to the list
        Parameters:
        Font - The index of the font
        fdPrivateBase - The IndexBaseItem array for the linked list
        fdSubrs - OffsetItem array for the linked list
      • CalcSubrOffsetSize

        private int CalcSubrOffsetSize​(int Offset,
                                       int Size)
        Calculates how many byte it took to write the offset for the subrs in a specific private dict.
        Parameters:
        Offset - The Offset for the private dict
        Size - The size of the private dict
        Returns:
        The size of the offset of the subrs in the private dict
      • CreateNonCIDPrivate

        private void CreateNonCIDPrivate​(int Font,
                                         CFFFont.OffsetItem Subr)
        The function creates a private dict for a font that was not CID All the keys are copied as is except for the subrs key
        Parameters:
        Font - the font
        Subr - The OffsetItem for the subrs of the private
      • CreateNonCIDSubrs

        private void CreateNonCIDSubrs​(int Font,
                                       CFFFont.IndexBaseItem PrivateBase,
                                       CFFFont.OffsetItem Subrs)
        the function marks the beginning of the subrs index and adds the subsetted subrs index to the output list.
        Parameters:
        Font - the font
        PrivateBase - IndexBaseItem for the private that's referencing to the subrs
        Subrs - OffsetItem for the subrs