< Linux samples

ElementEditTest - Python

The sample code shows how to edit the page display list and how to modify graphics state attributes on existing Elements. In particular the sample program strips all images from the page and changes text color to blue.

#---------------------------------------------------------------------------------------
# Copyright (c) 2001-2018 by PDFTron Systems Inc. All Rights Reserved.
# Consult LICENSE.txt regarding license information.
#---------------------------------------------------------------------------------------

import site
site.addsitedir("../../../PDFNetC/Lib")
import sys
from PDFNetPython import *

#---------------------------------------------------------------------------------------
# The sample code shows how to edit the page display list and how to modify graphics state 
# attributes on existing Elements. In particular the sample program strips all images from 
# the page and changes text color to blue. 
#---------------------------------------------------------------------------------------

def ProcessElements(reader, writer, map):
    element = reader.Next()     # Read page contents
    while element != None:
        type = element.GetType()
        if type == Element.e_image:
            # remove all images by skipping them
            pass
        elif type == Element.e_inline_image:            
            # remove all images by skipping them
            pass
        elif type == Element.e_text:    # Process text strings...
            # Set all text to blue color.
            gs = element.GetGState()
            gs.SetFillColorSpace(ColorSpace.CreateDeviceRGB())
            cp = ColorPt(0, 0, 1)
            gs.SetFillColor(cp)
            writer.WriteElement(element)
        elif type == Element.e_form:    # Recursively process form XObjects
            o = element.GetXObject()
            map[o.GetObjNum()] = o
            writer.WriteElement(element)
            pass
        else:
            writer.WriteElement(element)
        element = reader.Next()

def main():
    PDFNet.Initialize()
    
    # Relative path to the folder containing the test files.
    input_path = "../../TestFiles/"
    output_path = "../../TestFiles/Output/"
    input_filename = "newsletter.pdf"
    output_filename = "newsletter_edited.pdf"
    
    print("-------------------------------------------------")
    
    # Open the test file
    print("Opening the input file...")
    doc = PDFDoc(input_path + input_filename)
    doc.InitSecurityHandler()
    
    writer = ElementWriter()
    reader = ElementReader()
    
    itr = doc.GetPageIterator()
    
    while itr.HasNext():
        page = itr.Current()
        reader.Begin(page)
        writer.Begin(page, ElementWriter.e_replacement, False)
        map1 = {}
        ProcessElements(reader, writer, map1)
        writer.End()
        reader.End()
		
        map2 = {}
        while (map1 or map2):
            for k in map1.keys():
                obj = map1[k]
                writer.Begin(obj)
                reader.Begin(obj, page.GetResourceDict())
                ProcessElements(reader, writer, map2)
                reader.End()
                writer.End()

                del map1[k]
            if (not map1 and map2):
                map1.update(map2)
                map2.clear()
        itr.Next()
        
    doc.Save(output_path + output_filename, SDFDoc.e_remove_unused)
    doc.Close()
    print("Done. Result saved in " + output_filename +"...")
    
if __name__ == '__main__':
    main()