add double-page-size example

git-svn-id: svn+q:///qpdf/trunk@996 71b93d88-0707-0410-a8cf-f5a4172ac649

ChangeLog

@@ -1,5 +1,9 @@
 2010-08-05  Jay Berkenbilt  <ejb@ql.org>
 
+	* Add QPDFObjectHandle::addPageContents, a convenience routine for
+	appending or prepending new streams to a page's content streams.
+	The "double-page-size" example illustrates its use.
+
 	* Add new methods to QPDFObjectHandle: replaceStreamData and
 	newStream.  These methods allow users of the qpdf library to add
 	new streams and to replace data of existing streams.  Examples are

TODO

@@ -7,9 +7,9 @@ Next
    in August, 2009.  He seems to like to send encrypted mail (key
    01FCC336).  Tell him about newStream and replaceStreamData.
 
- * Tell stronghorse@tom.com about QPDFObjectHandle::addPageContents.
+ * Tell stronghorse@tom.com about QPDFObjectHandle::addPageContents
-   See message from stronghorse@tom.com ("Suggestion for qpdf") from
+   and double-page-size example.  See message from stronghorse@tom.com
-   2010-06-09 and my response.
+   ("Suggestion for qpdf") from 2010-06-09 and my response.
 
 2.2
 ===
@@ -18,8 +18,6 @@ Next
    image.  Use QPDF::getAllPages and QPDFObjectHandle::getPageImages
    along with new stream data and dictionary manipulation.
 
- * Add example program for addPageContents using suggestion from
-   stronghorse@tom.com's message above.
 
 General
 =======

examples/build.mk

@@ -1,4 +1,4 @@
-BINS_examples = pdf-bookmarks pdf-mod-info pdf-npages
+BINS_examples = pdf-bookmarks pdf-mod-info pdf-npages double-page-size
 CBINS_examples = pdf-linearize
 
 TARGETS_examples = $(foreach B,$(BINS_examples) $(CBINS_examples),examples/$(OUTPUT_DIR)/$(call binname,$(B)))

examples/double-page-size.cc

@@ -0,0 +1,113 @@
+#include <iostream>
+#include <string.h>
+#include <stdlib.h>
+#include <qpdf/QPDF.hh>
+#include <qpdf/QUtil.hh>
+#include <qpdf/Buffer.hh>
+#include <qpdf/QPDFWriter.hh>
+
+static char const* whoami = 0;
+
+void usage()
+{
+    std::cerr << "Usage: " << whoami << " infile.pdf outfile.pdf [in-password]"
+	      << std::endl
+	      << "Double size of all pages in infile.pdf;"
+	      << " write output to outfile.pdf" << std::endl;
+    exit(2);
+}
+
+static void doubleBoxSize(QPDFObjectHandle& page, char const* box_name)
+{
+    QPDFObjectHandle box = page.getKey(box_name);
+    if (box.isNull())
+    {
+	return;
+    }
+    if (! (box.isArray() && (box.getArrayNItems() == 4)))
+    {
+	throw std::runtime_error(std::string("box ") + box_name +
+				 " is not an array of four elements");
+    }
+    std::vector<QPDFObjectHandle> doubled;
+    for (unsigned int i = 0; i < 4; ++i)
+    {
+	doubled.push_back(
+	    QPDFObjectHandle::newReal(
+		QUtil::double_to_string(
+		    box.getArrayItem(i).getNumericValue() * 2.0, 2)));
+    }
+    page.replaceKey(box_name, QPDFObjectHandle::newArray(doubled));
+}
+
+int main(int argc, char* argv[])
+{
+    whoami = QUtil::getWhoami(argv[0]);
+
+    // For libtool's sake....
+    if (strncmp(whoami, "lt-", 3) == 0)
+    {
+	whoami += 3;
+    }
+
+    if (! ((argc == 3) || (argc == 4)))
+    {
+	usage();
+    }
+
+    char const* infilename = argv[1];
+    char const* outfilename = argv[2];
+    char const* password = (argc == 4) ? argv[3] : "";
+
+    // Text to prepend to each page's contents
+    char const* content = "2 0 0 2 0 0 cm\n";
+
+    // Copy text into a buffer without the null terminator
+    PointerHolder<Buffer> b = new Buffer(strlen(content));
+    unsigned char* bp = b.getPointer()->getBuffer();
+    memcpy(bp, (unsigned char*)content, strlen(content));
+
+    try
+    {
+	QPDF qpdf;
+	qpdf.processFile(infilename, password);
+
+	std::vector<QPDFObjectHandle> pages = qpdf.getAllPages();
+	for (std::vector<QPDFObjectHandle>::iterator iter = pages.begin();
+	     iter != pages.end(); ++iter)
+	{
+	    QPDFObjectHandle& page = *iter;
+
+	    // Prepend the buffer to the page's contents
+	    page.addPageContents(QPDFObjectHandle::newStream(&qpdf, b), true);
+
+	    // Double the size of each of the content boxes
+	    doubleBoxSize(page, "/MediaBox");
+	    doubleBoxSize(page, "/CropBox");
+	    doubleBoxSize(page, "/BleedBox");
+	    doubleBoxSize(page, "/TrimBox");
+	    doubleBoxSize(page, "/ArtBox");
+	}
+
+	// Write out a new file
+	QPDFWriter w(qpdf, outfilename);
+	if (QUtil::get_env("IN_TESTSUITE"))
+	{
+	    // For the test suite, uncompress streams and use static
+	    // IDs.
+	    w.setStaticID(true);
+	    w.setStreamDataMode(qpdf_s_uncompress);
+	}
+	w.write();
+	std::cout << whoami << ": new file written to " << outfilename
+		  << std::endl;
+    }
+    catch (std::exception &e)
+    {
+	std::cerr << whoami << " processing file " << infilename << ": "
+		  << e.what() << std::endl;
+	exit(2);
+    }
+
+    return 0;
+}

examples/qtest/double-page-size.test

@@ -0,0 +1,31 @@
+#!/usr/bin/env perl
+require 5.008;
+BEGIN { $^W = 1; }
+use strict;
+
+chdir("double-page-size") or die "chdir testdir failed: $!\n";
+
+require TestDriver;
+
+my $td = new TestDriver('double-page-size');
+
+cleanup();
+
+$td->runtest("double page size",
+	     {$td->COMMAND => "double-page-size in.pdf a.pdf"},
+	     {$td->STRING => "double-page-size: new file written to a.pdf\n",
+	      $td->EXIT_STATUS => 0},
+	     $td->NORMALIZE_NEWLINES);
+
+$td->runtest("check output",
+	     {$td->FILE => "a.pdf"},
+	     {$td->FILE => "out.pdf"});
+
+cleanup();
+
+$td->report(2);
+
+sub cleanup
+{
+    unlink 'a.pdf';
+}

examples/qtest/double-page-size/in.pdf

@@ -0,0 +1,55 @@
+%PDF-1.3
+%¿÷¢þ
+1 0 obj
+<< /Pages 2 0 R /Type /Catalog >>
+endobj
+2 0 obj
+<< /Count 2 /Kids [ 3 0 R 4 0 R ] /Type /Pages >>
+endobj
+3 0 obj
+<< /Contents 5 0 R /MediaBox [ 0 0 612 792 ] /Parent 2 0 R /Resources << /Font << /F1 6 0 R >> /ProcSet 7 0 R >> /Type /Page >>
+endobj
+4 0 obj
+<< /Contents 8 0 R /MediaBox [ 0 0 612 792 ] /Parent 2 0 R /Resources << /Font << /F1 6 0 R >> /ProcSet 7 0 R >> /Type /Page >>
+endobj
+5 0 obj
+<< /Length 44 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato) Tj
+ET
+endstream
+endobj
+6 0 obj
+<< /BaseFont /Helvetica /Encoding /WinAnsiEncoding /Name /F1 /Subtype /Type1 /Type /Font >>
+endobj
+7 0 obj
+[ /PDF /Text ]
+endobj
+8 0 obj
+<< /Length 43 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Salad) Tj
+ET
+endstream
+endobj
+xref
+0 9
+0000000000 65535 f 
+0000000015 00000 n 
+0000000064 00000 n 
+0000000129 00000 n 
+0000000272 00000 n 
+0000000415 00000 n 
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+0000000645 00000 n 
+trailer << /Root 1 0 R /Size 9 /ID [<071a6499182be9cfc990b11d0c4e5bc0><90dbb2f2f000af76d1107187b0e00349>] >>
+startxref
+737
+%%EOF

examples/qtest/double-page-size/out.pdf

@@ -0,0 +1,69 @@
+%PDF-1.3
+%¿÷¢þ
+1 0 obj
+<< /Pages 2 0 R /Type /Catalog >>
+endobj
+2 0 obj
+<< /Count 2 /Kids [ 3 0 R 4 0 R ] /Type /Pages >>
+endobj
+3 0 obj
+<< /Contents [ 5 0 R 6 0 R ] /MediaBox [ 0.00 0.00 1224.00 1584.00 ] /Parent 2 0 R /Resources << /Font << /F1 7 0 R >> /ProcSet 8 0 R >> /Type /Page >>
+endobj
+4 0 obj
+<< /Contents [ 9 0 R 10 0 R ] /MediaBox [ 0.00 0.00 1224.00 1584.00 ] /Parent 2 0 R /Resources << /Font << /F1 7 0 R >> /ProcSet 8 0 R >> /Type /Page >>
+endobj
+5 0 obj
+<< /Length 15 >>
+stream
+2 0 0 2 0 0 cm
+endstream
+endobj
+6 0 obj
+<< /Length 44 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Potato) Tj
+ET
+endstream
+endobj
+7 0 obj
+<< /BaseFont /Helvetica /Encoding /WinAnsiEncoding /Name /F1 /Subtype /Type1 /Type /Font >>
+endobj
+8 0 obj
+[ /PDF /Text ]
+endobj
+9 0 obj
+<< /Length 15 >>
+stream
+2 0 0 2 0 0 cm
+endstream
+endobj
+10 0 obj
+<< /Length 43 >>
+stream
+BT
+  /F1 24 Tf
+  72 720 Td
+  (Salad) Tj
+ET
+endstream
+endobj
+xref
+0 11
+0000000000 65535 f 
+0000000015 00000 n 
+0000000064 00000 n 
+0000000129 00000 n 
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+0000000464 00000 n 
+0000000528 00000 n 
+0000000621 00000 n 
+0000000728 00000 n 
+0000000758 00000 n 
+0000000822 00000 n 
+trailer << /Root 1 0 R /Size 11 /ID [<071a6499182be9cfc990b11d0c4e5bc0><31415926535897932384626433832795>] >>
+startxref
+915
+%%EOF