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<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Adjusting the output</title><link rel="stylesheet" type="text/css" href="manual.css"><meta name="generator" content="DocBook XSL Stylesheets V1.76.0"><link rel="home" href="index.html" title="JpGraph Manual"><link rel="up" href="ch25.html" title="Chapter 25. PDF417 (2D-Barcode)"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Adjusting the output</th></tr><tr><td width="20%" align="left"> </td><th width="60%" align="center">Chapter 25. PDF417 (2D-Barcode)</th><td width="20%" align="right"> </td></tr></table><hr></div><div class="sect1" title="Adjusting the output"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2602084"></a>Adjusting the output</h2></div></div></div>
<p>This section deals with the way you can adjust the visual quality and appearance of
the output by adjusting a number of properties on the backend.</p>
<div class="sect2" title="Output format"><div class="titlepage"><div><div><h3 class="title"><a name="id2602136"></a>Output format</h3></div></div></div>
<p>By choosing the appropriate backend you can choose to generate the barcode label
as either an image (in either PNG or JPEG format) or as Postscript (both standalone
and Encapsulated postscript) . For images the PNG is strongly recommended and used
by default. The reason is that PNG is a non-destructive format and will ensure the
maximum quality of the barcodes while JPEG is not well suited for this type of
applications since it is a destructive format. </p>
<p>This choice is being made by creating the appropriate backend. The backend is
created by calling the factory method <code class="code">PDF417BackendFactory::Create()</code>
specifying what type of backend and what encoder to use. The backend factory will
then return a suitable encoder.</p>
<p>The following code snippet shows how to create a backend that will generate an
image.</p>
<p>
</p><div class="hl-main"><table class="hl-table" width="100%"><tr><td class="hl-gutter" align="right" valign="top"><pre>1
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</pre></td><td class="hl-main" valign="top"><pre><span class="hl-inlinetags"><?php</span><span class="hl-code">
</span><span class="hl-comment">//</span><span class="hl-comment"> Create a new encode using the default error correction</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-comment">//</span><span class="hl-comment"> and columns</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-var">$encoder</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">PDF417Barcode</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-var">$backend</span><span class="hl-code"> = </span><span class="hl-identifier">PDF417BackendFactory</span><span class="hl-code">::</span><span class="hl-identifier">Create</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">BACKEND_IMAGE</span><span class="hl-code">, </span><span class="hl-var">$encoder</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-inlinetags">?></span></pre></td></tr></table></div><p>
</p>
<p>It is also possible to have one encoder and two different backends to allow the
creation of both image and postscript output at the same time as the following
example shows </p>
<p>
</p><div class="hl-main"><table class="hl-table" width="100%"><tr><td class="hl-gutter" align="right" valign="top"><pre>1
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</pre></td><td class="hl-main" valign="top"><pre><span class="hl-inlinetags"><?php</span><span class="hl-code">
</span><span class="hl-var">$date</span><span class="hl-code">=</span><span class="hl-quotes">'</span><span class="hl-string">ABC123</span><span class="hl-quotes">'</span><span class="hl-code">;
</span><span class="hl-var">$file</span><span class="hl-code">=</span><span class="hl-quotes">'</span><span class="hl-string"> ...</span><span class="hl-quotes">'</span><span class="hl-code">; </span><span class="hl-comment">//</span><span class="hl-comment"> Some filename to write the PS file to</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-comment">//</span><span class="hl-comment"> Create a new encode using the default error correction</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-comment">//</span><span class="hl-comment"> and columns</span><span class="hl-comment"></span><span class="hl-code">
</span><span class="hl-var">$encoder</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">PDF417Barcode</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-var">$eImg</span><span class="hl-code"> = </span><span class="hl-identifier">PDF417BackendFactory</span><span class="hl-code">::</span><span class="hl-identifier">Create</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">BACKEND_IMAGE</span><span class="hl-code">, </span><span class="hl-var">$encoder</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-var">$eEPS</span><span class="hl-code"> = </span><span class="hl-identifier">PDF417BackendFactory</span><span class="hl-code">::</span><span class="hl-identifier">Create</span><span class="hl-brackets">(</span><span class="hl-code"> </span><span class="hl-identifier">BACKEND_EPS</span><span class="hl-code">, </span><span class="hl-var">$encoder</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-var">$eEPS</span><span class="hl-code">-></span><span class="hl-identifier">Stroke</span><span class="hl-brackets">(</span><span class="hl-var">$data</span><span class="hl-code">,</span><span class="hl-var">$file</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-var">$eImg</span><span class="hl-code">-></span><span class="hl-identifier">Stroke</span><span class="hl-brackets">(</span><span class="hl-var">$data</span><span class="hl-brackets">)</span><span class="hl-code">;
</span><span class="hl-inlinetags">?></span></pre></td></tr></table></div><p>
</p>
</div>
<div class="sect2" title="Summary of user settings for the backend"><div class="titlepage"><div><div><h3 class="title"><a name="id2602186"></a>Summary of user settings for the backend</h3></div></div></div>
<p>In the list below is a short description of the available possibilities to change
the output. For a more detailed explanation of the parameters for each method please
consult the method reference at the end of this chapter</p>
<p>
</p><div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem">
<p><span class="bold"><strong>Specifying the module width.</strong></span> The
module width for the barcode is user selectable, For images this
specifies the number of pixels for the module and for Postscript output
this specifies the number of points (1/72 inch).</p>
</li><li class="listitem">
<p><span class="bold"><strong>Specifying the width/height factor</strong></span>
Specify the height of each individual row in the barcode as a multiple
of the width. By default the height is 3x the width.</p>
</li><li class="listitem">
<p><span class="bold"><strong>Specifying background and foreground
color</strong></span> The foreground color and the background color for
the barcodes are user selectable. The colors can be specified as any of
JpGraphs builtin colors.</p>
</li><li class="listitem">
<p><span class="bold"><strong>Adding human readable text</strong></span> This is an
extension to the PDF417 standard. This adds a plaintext string of the
data that has been encoded under the barcode. This is useful when
debugging applications to make sure that the right values have been
read, for example, from a DB.</p>
</li><li class="listitem">
<p>Rotating 90 degrees (Vertical output) This enables the barcode to be
printed vertically.</p>
</li><li class="listitem">
<p>Scaling the image The resulting barcode images can be scaled by an
arbitrary factor.</p>
</li></ul></div><p>
</p>
</div>
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