How can PHP's GD library be used to create visual representations like timelines or charts based on data processed in PHP?

To create visual representations like timelines or charts based on data processed in PHP, you can utilize PHP's GD library to generate images dynamically. By using GD functions, you can create various types of charts, graphs, and visual representations based on the data you have processed in PHP.

// Example code to create a simple bar chart using PHP's GD library
$data = [20, 40, 60, 80]; // Sample data for the bar chart

// Create a blank image with specified dimensions
$image = imagecreate(400, 300);

// Define colors for the chart
$white = imagecolorallocate($image, 255, 255, 255);
$black = imagecolorallocate($image, 0, 0, 0);
$blue = imagecolorallocate($image, 0, 0, 255);

// Draw the bars on the chart based on the data
$barWidth = 50;
$spacing = 20;
$x = 50;
foreach ($data as $value) {
    imagefilledrectangle($image, $x, 250, $x + $barWidth, 250 - $value, $blue);
    $x += $barWidth + $spacing;
}

// Output the image
header('Content-type: image/png');
imagepng($image);

// Clean up
imagedestroy($image);