This example shows how EncodeImage can be used to embed a PHPlot image inside an HTML file using the 'data:' URL scheme. Note: This feature was added in PHPlot-5.5.0.
This is the same plot as Section 5.2, “Example - Line Plot: Functions”, except instead of producing the image on standard output, this script embeds the image in an HTML page, which is produced on standard output. The screenshot below shows how the web page looks in Firefox.
Example 5.39. Embedding Image with EncodeImage (Browser screenshot)
<?php
# PHPlot Example: Using 'data:' URL scheme to embed an image
# Unlike other examples, this outputs a complete HTML page with embedded image.
require_once 'phplot.php';
# Generate data for: Y1 = sin(x), Y2 = cos(x)
$end = M_PI * 2.0;
$delta = $end / 20.0;
$data = array();
for ($x = 0; $x <= $end; $x += $delta)
$data[] = array('', $x, sin($x), cos($x));
$plot = new PHPlot(800, 600);
$plot->SetFailureImage(False); // No error images
$plot->SetPrintImage(False); // No automatic output
$plot->SetImageBorderType('plain');
$plot->SetPlotType('lines');
$plot->SetDataType('data-data');
$plot->SetDataValues($data);
$plot->SetTitle('Line Plot, Sin and Cos - Embedded Image');
$plot->SetLegend(array('sin(t)', 'cos(t)'));
$plot->SetPlotAreaWorld(0, -1, 6.8, 1);
$plot->SetXDataLabelPos('none');
$plot->SetXTickIncrement(M_PI / 8.0);
$plot->SetXLabelType('data');
$plot->SetPrecisionX(3);
$plot->SetYTickIncrement(0.2);
$plot->SetYLabelType('data');
$plot->SetPrecisionY(1);
$plot->SetDrawXGrid(True);
$plot->SetDrawYGrid(True);
$plot->DrawGraph();
?><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>PHPlot Example - Inline Image</title>
</head>
<body>
<h1>PHPlot Example - Inline Image</h1>
<p>This is a plot of sin() and cos().</p>
<img src="<?php echo $plot->EncodeImage();?>" alt="Plot Image">
</body>
</html>