pdf_flavors/transparent_stamp_for_pdfa

Apply a transparent stamp to an existing PDF/A document while maintaining PDF/A conformance.
Import all pages from an existing PDF/A document and place a stamp on the page. The stamp is filled with a pattern color, where the pattern consists of a bitmap. The bitmap is used as a mask to create a certain percentage of transparency. This is required since real transparency is not allowed in PDF/A. Transparency by pattern color is PDF/A compatible, so we use it to apply a transparent stamp on a PDF/A document while maintaining PDF/A conformance.
Note: On Windows systems the "Arial-Bold" font is installed by default. On other systems, you may have to load another font if the "Arial-Bold" font is not available.

Download Java Code Show Output PDF

/* $Id: transparent_stamp_for_pdfa.java,v 1.4 2008/04/08 15:35:23 katja Exp $

* Transparent stamp for PDF/A:

* Apply a transparent stamp to an existing PDF/A document while maintaining

* PDF/A conformance.

* Import all pages from an existing PDF/A document and place a stamp on the

* page. The stamp is filled with a pattern color, where the pattern consists of

* a bitmap. The bitmap is used as a mask to create a certain percentage of

* transparency. This is required since real transparency is not allowed in

* PDF/A. Transparency by pattern color is PDF/A compatible, so we use it to

* apply a transparent stamp on a PDF/A document while maintaining PDF/A

* conformance.

* Note: On Windows systems the "Arial-Bold" font is installed by default.

* On other systems, you may have to load another font if the "Arial-Bold" font

* is not available.

* Required software: PDFlib+PDI/PPS 7

* Required data: PDF document

package com.pdflib.cookbook.pdflib.pdf_flavors;

import com.pdflib.pdflib;

import com.pdflib.PDFlibException;

public class transparent_stamp_for_pdfa

{

public static void main (String argv[])

{

/* This is where the data files are. Adjust as necessary. */

String searchpath = "../input";

String outfile = "transparent_stamp_for_pdfa.pdf";

String title = "Transparent Stamp for PDF/A";

pdflib p = null;

String pdffile = "PLOP-datasheet-PDFA-1b.pdf";

int indoc, pageno, endpage, page, font, pattern;

double w;

double ret;

String res;

int image;

/* data set for our haftoning bitmap */

int data[][] = {

{ 0x00, 0x00, /* 30% */

0x00, 0x00,

0x03, 0xC0,

0x07, 0xE0,

0x0F, 0xF0,

0x1F, 0xF8,

0x0F, 0xF0,

0x07, 0xE0,

0x03, 0xC0,

0x00, 0x00,

{ 0x00, 0x00, /* 20% */

0x00, 0x00,

0x03, 0xC0,

0x07, 0xE0,

0x0F, 0xF0,

0x07, 0xE0,

0x03, 0xC0,

0x00, 0x00,

}};

int ht = 1; /* index in halftone array */

try {

p = new pdflib();

p.set_parameter("SearchPath", searchpath);

/* This means we must check return values of load_font() etc. */

p.set_parameter("errorpolicy", "return");

if (p.begin_document(outfile, "pdfa=PDF/A-1b:2005") == -1)

throw new Exception("Error: " + p.get_errmsg());

p.set_info("Creator", "PDFlib Cookbook");

p.set_info("Title", title + " $Revision: 1.4 $");

/* -----------------------------------------------------------------

* Open the input PDF.

* This must be done before creating the pattern because the output

* intent must be set before defining the pattern.

* -----------------------------------------------------------------

indoc = p.open_pdi_document(pdffile, "");

if (indoc == -1)

throw new Exception("Error: " + p.get_errmsg());

endpage = (int) p.pcos_get_number(indoc, "/Root/Pages/Count");

/* Since the input document contains its own output intent retrieve

* the output intent from the input document and copy it to the output

* document.

res = p.pcos_get_string(indoc, "type:/Root/OutputIntents");

if (res.equals("array")) {

ret = p.process_pdi(indoc, -1, "action=copyoutputintent");

if (ret == -1)

throw new Exception("Error: " + p.get_errmsg());

}

/* -------------------------------------------------------------------

* Define a bitmap pattern based on an image mask.

* We scale down the image to provide a smoother appearance on screen.

* -------------------------------------------------------------------

byte [] bitmap = new byte[data[ht].length];

for (int j=0; j < data[ht].length; j++)

bitmap[j] = (byte) data[ht][j];

p.create_pvf("/pvf/font/bitmap", bitmap, "");

image = p.load_image("raw", "/pvf/font/bitmap",

"bpc=1 components=1 height=16 width=16 invert mask");

if (image == -1)

throw new Exception("Error: " + p.get_errmsg());

w = (double) 16/32;

pattern = p.begin_pattern(w, w, w, w, 1);

p.fit_image(image, 0, 0, "scale=" + (double) 1/32);

p.end_pattern();

p.close_image(image);

/* Loop over all pages of the input document */

for (pageno = 1; pageno <= endpage; pageno++)

{

page = p.open_pdi_page(indoc, pageno, "");

if (page == -1)

throw new Exception("Error: " + p.get_errmsg());

/* Dummy page size; will be adjusted later */

p.begin_page_ext(10, 10, "");

/* Place the imported page on the output page, and adjust the page

* size.

p.fit_pdi_page(page, 0, 0, "adjustpage");

/* On Windows systems the "Arial-Bold" font is installed by default.

* On other systems, you may have to load another font if the

* "Arial-Bold" font is not available.

* On Non-Windows systems use the "FontOutline" resource category to

* define a font name to be used by PDFlib as follows. Set the

* searchpath to the path of the font file. Then, connect the font

* name "Arial,Bold" to the TrueType outline font file

* "ARIALBD.TTF".

* p.set_parameter("SearchPath", "path/to/font file");

* p.set_parameter("FontOutline", "Arial,Bold=ARIALBD.TTF");

* Alternatively, you can omit the search path and directly extend

* the font name by the path.

font = p.load_font("Arial,Bold", "unicode", "embedding");

if (font == -1)

throw new Exception("Error: " + p.get_errmsg());

/* Place the stamp, filled with the pattern color */

p.setcolor("fill", "pattern", pattern, 0, 0, 0);

p.fit_textline("PUBLISHED", 20, 20,

"font=" + font + " fontsize=1 boxsize={550 800} stamp=ll2ur");

p.close_pdi_page(page);

p.end_page_ext("");

}

p.end_document("");

} catch (PDFlibException e){

System.err.print("PDFlib exception occurred:\n");

System.err.print("[" + e.get_errnum() + "] " + e.get_apiname() +

": " + e.get_errmsg() + "\n");

} catch (Exception e) {

System.err.println(e.getMessage());

} finally {

if (p != null) {

p.delete();

}