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PHP gd_info() Function: Usage and Examples

Reports the installed GD library version and enabled format or codec features.

1 views Published Oct 17, 2026 Updated Oct 17, 2026 admin

Reports the installed GD library version and enabled format or codec features.

What It Does


GD provides simple pixel-level operations; Imagick provides another image-processing API with distinct requirements. Feature names and available decoders depend on the installed GD build.

Requirements and Compatibility


GD extension. Sample images and fonts referred to by filename must be supplied locally. Use PHP 8 GdImage objects where applicable; optional decoders depend on the installed build.

Syntax, Inputs and Results


The arguments shown below are concrete values for this function; their types and ranges matter. The example checks return data rather than assuming that every operation succeeds.

Example 1: Basic Use


Call the function with a concrete input and inspect its result.

<?php
if (!extension_loaded('gd')) throw new RuntimeException('GD extension required');
$result = gd_info();
print_r($result);

Example 2: Another Case


Change the inputs to observe the behavior on another case.

<?php
if (!extension_loaded('gd')) throw new RuntimeException('GD extension required');
$result = gd_info()["JPEG Support"] ?? false;
print_r($result);

Practical Example


Use the result to create an output, validate a condition, or complete an image workflow.

<?php
$capabilities = gd_info();
if (!($capabilities["JPEG Support"] ?? false)) throw new RuntimeException("GD JPEG support required");

For production, apply the compatibility and edge-case limits described below.

Important Behavior and Edge Cases


Feature names and available decoders depend on the installed GD build.

Comparison with Related Functions and Tools


SubjectKey difference
gd_info()GD provides simple pixel-level operations; Imagick provides another image-processing API with distinct requirements.

Common Beginner Mistakes


MistakeCorrect approach
Calling gd_info() without its required input or supported extensionCheck the extension, supply valid arguments, and handle false or exceptions according to the function.
Assuming gd_info() guarantees a valid or safe imageFeature names and available decoders depend on the installed GD build.
Confusing the operation with a related APIGD provides simple pixel-level operations; Imagick provides another image-processing API with distinct requirements.

Key Takeaways


  • Reports the installed GD library version and enabled format or codec features.
  • Feature names and available decoders depend on the installed GD build.
  • Choose the companion API described in the comparison table when the job differs.

Use these examples as a starting point, then validate the result with the actual PHP build, dependencies and inputs used by your application.

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