Package org.apache.fop.pdf

Class PDFImageXObject

  • All Implemented Interfaces:
    PDFWritable
    public class PDFImageXObject
extends PDFXObject
    PDF XObject A derivative of the PDF Object, is a PDF Stream that has not only a dictionary but a stream of image data. The dictionary just provides information like the stream length. This outputs the image dictionary and the image data. This is used as a reference for inserting the same image in the document in another place.

    • Constructor Detail

      • PDFImageXObject

        public PDFImageXObject​(int xnumber,
                       PDFImage img)
        create an XObject with the given number and name and load the image in the object
        Parameters:
        xnumber - the pdf object X number
        img - the pdf image that contains the image data

    • Method Detail

      • output

        public int output​(java.io.OutputStream stream)
           throws java.io.IOException
        Output the image as PDF. This sets up the image dictionary and adds the image data stream.
        Overrides:
        output in class AbstractPDFStream
        Parameters:
        stream - the output stream to write the data
        Returns:
        the length of the data written
        Throws:
        java.io.IOException - if there is an error writing the data

      • populateStreamDict

        protected void populateStreamDict​(java.lang.Object lengthEntry)
        Populates the dictionary with all necessary entries for the stream. Override this method if you need additional entries.
        Overrides:
        populateStreamDict in class PDFXObject
        Parameters:
        lengthEntry - value for the /Length entry

      • outputRawStreamData

        protected void outputRawStreamData​(java.io.OutputStream out)
                            throws java.io.IOException
        Sends the raw stream data to the target OutputStream.
        Specified by:
        outputRawStreamData in class AbstractPDFStream
        Parameters:
        out - OutputStream to write to
        Throws:
        java.io.IOException - In case of an I/O problem

      • getSizeHint

        protected int getSizeHint()
                   throws java.io.IOException
        Returns a value that hints at the size of the encoded stream. This is used to optimize buffer allocation so fewer buffer reallocations are necessary.
        Overrides:
        getSizeHint in class PDFXObject
        Returns:
        an estimated size (0 if no hint can be given)
        Throws:
        java.io.IOException - in case of an I/O problem

      • prepareImplicitFilters

        protected void prepareImplicitFilters()
        Prepares implicit filters (such as the DCTFilter for JPEG images). You must make sure that the appropriate filters are in the filter list at the right places.
        Overrides:
        prepareImplicitFilters in class AbstractPDFStream

      • getDefaultFilterName

        protected java.lang.String getDefaultFilterName()
        Returns the name of a suitable filter for this PDF object. This class uses the PDFImage instance to determine the default filter.
        Overrides:
        getDefaultFilterName in class AbstractPDFStream
        Returns:
        the default filter
        See Also:
        PDFFilterList

      • multipleFiltersAllowed

        protected boolean multipleFiltersAllowed()
        Whether multiple filters can be applied.
        Overrides:
        multipleFiltersAllowed in class AbstractPDFStream
        Returns:
        true if multiple filters allowed