Extracts an existing embedded EXIF thumbnail as binary image data.
What It Does
getimagesize() reads dimensions; EXIF functions inspect metadata or image signatures. It does not generate thumbnails; false can mean no embedded thumbnail.
Requirements and Compatibility
EXIF 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 (!is_file(__DIR__ . '/photo.jpg')) throw new RuntimeException('Provide the sample file /photo.jpg');
$thumbnail = exif_thumbnail(__DIR__ . '/photo.jpg', $width, $height, $type);
if ($thumbnail === false) { echo 'No embedded thumbnail'; } else { echo strlen($thumbnail), ' bytes'; }Example 2: Another Case
Change the inputs to observe the behavior on another case.
<?php
if (!is_file(__DIR__ . '/portrait.jpg')) throw new RuntimeException('Provide the sample file /portrait.jpg');
$thumbnail = exif_thumbnail(__DIR__ . '/portrait.jpg', $w, $h, $format);
if ($thumbnail === false) { echo 'No embedded thumbnail'; } else { echo strlen($thumbnail), ' bytes'; }Practical Example
Use the result to create an output, validate a condition, or complete an image workflow.
<?php
$file = __DIR__ . '/photo.jpg';
if (!is_file($file)) throw new RuntimeException('Missing sample');
$thumbnail = exif_thumbnail($file, $w, $h, $type);
if ($thumbnail !== false && $type === IMAGETYPE_JPEG) {
file_put_contents(__DIR__ . '/embedded-preview.jpg', $thumbnail);
}For production, apply the compatibility and edge-case limits described below.
Important Behavior and Edge Cases
It does not generate thumbnails; false can mean no embedded thumbnail.
Comparison with Related Functions and Tools
| Subject | Key difference |
|---|---|
| exif_thumbnail() | getimagesize() reads dimensions; EXIF functions inspect metadata or image signatures. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Calling exif_thumbnail() without its required input or supported extension | Check the extension, supply valid arguments, and handle false or exceptions according to the function. |
| Assuming exif_thumbnail() guarantees a valid or safe image | It does not generate thumbnails; false can mean no embedded thumbnail. |
| Confusing the operation with a related API | getimagesize() reads dimensions; EXIF functions inspect metadata or image signatures. |
Key Takeaways
- Extracts an existing embedded EXIF thumbnail as binary image data.
- It does not generate thumbnails; false can mean no embedded thumbnail.
- 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.