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How to implement guide with php's gd library generating images with transparency on a png

👀 Views: 13 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-12
php gd image-manipulation PHP

I recently switched to I've been banging my head against this for hours... I'm sure I'm missing something obvious here, but I tried several approaches but none seem to work... I'm having trouble generating a transparent PNG image using PHP's GD library. My goal is to create a simple image with a transparent background and draw some text on it. However, the generated image does not maintain transparency and shows a black background instead. I am using PHP 8.0 and GD version 2.3.1. Here's the code I'm using: ```php header('Content-Type: image/png'); // Create a blank image with dimensions 200x100 $image = imagecreatetruecolor(200, 100); // Enable transparency imagealphablending($image, false); imagesavealpha($image, true); // Fill the image with a transparent color $transparent = imagecolorallocatealpha($image, 255, 255, 255, 127); imagefill($image, 0, 0, $transparent); // Set the text color to black $textColor = imagecolorallocate($image, 0, 0, 0); // Draw the text on the image $text = 'Hello, World!'; imagestring($image, 5, 10, 40, $text, $textColor); // Output the image imagepng($image); // Free up memory imagedestroy($image); ``` When I run this code, the output shows a black rectangle instead of a transparent background. I've tried setting the blend mode and saving alpha transparency, but I'm still working with the same scenario. I've also checked the server configuration to ensure GD is correctly installed and configured. Could someone guide to understand why the transparency isn't working and how to resolve this scenario? This is part of a larger service I'm building. Has anyone else encountered this? This is part of a larger API I'm building. I'd really appreciate any guidance on this. I'm working with Php in a Docker container on CentOS. I appreciate any insights! Thanks for taking the time to read this!