images/transparent_images

 * Transparent images:

 * Create transparent images

 *

 * Display a colored background rectangle. Output two transparent background

 * images over that rectangle, then output a non-transparent image in the

 * foreground. Create transparency by applying an extended graphics

 * state with the "opacityfill" option set to a value less than 1.

 *

 * Required software: PDFlib/PDFlib+PDI/PPS 9

 * Required data: image file

 */

package com.pdflib.cookbook.pdflib.images;

import com.pdflib.pdflib;

import com.pdflib.PDFlibException;

public class transparent_images

{

    public static void main (String argv[])

    {

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

    String searchpath = "../input";

    String outfile = "transparent_images.pdf";

    String title = "Transparent Images";

    pdflib p = null;

    String imagefile = "nesrin.jpg";

    int image, gstate, font;

    try {

        p = new pdflib();

        p.set_option("searchpath={" + searchpath + "}");

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

        p.set_option("errorpolicy=return");

        if (p.begin_document(outfile, "") == -1)

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

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

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

        /* Load image */

        image = p.load_image("auto", imagefile, "");

        if (image == -1)

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

        /* Load the font. */

        font = p.load_font("Helvetica", "unicode", "");

        if (font == -1)

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

        /* Start page 1 */

        p.begin_page_ext(842, 595, "");

        /* Draw a yellow background rectangle */

        p.setcolor("fill", "rgb", 1, 0.9, 0.58, 0);

        p.rect(0, 0, 421, 595);

        p.fill();

        /* Display some descriptive text */

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

        p.fit_textline("Two transparent background images with a " +

            "non-transparent image placed in the foreground", 50, 530, "font=" +

            font + " fontsize=18");

        /* Save the current graphics state. The save/restore of the current

         * state is not necessarily required, but it will help you get back to

         * a graphics state without any transparency.

         */

        p.save();

        /* Create an extended graphics state with transparency set to 50%, using

         * create_gstate() with the "opacityfill" option set to 0.5.

         */

        gstate = p.create_gstate("opacityfill=.5");

        /* Apply the extended graphics state */

        p.set_gstate(gstate);

        /* Display two images which will be transparent according to the

         * graphics state set.

         */

        p.fit_image(image, 0, 0, "boxsize={842 595} position={center bottom}");

        p.fit_image(image, 0, 0, "boxsize={842 595} position={center bottom} " +

            "scale=0.7");

        /* Restore the current graphics state */

        p.restore();

        /* Display the image again. It will not be transparent since the old

         * graphics state has been restored with no transparency set.

         */

        p.fit_image(image, 0, 0, "boxsize={842 595} position={center bottom} " +

            "scale=0.35");

        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();

            }

        }

    }

}