Resolves a numeric EXIF tag identifier into its readable tag name.
What It Does
getimagesize() reads dimensions; EXIF functions inspect metadata or image signatures. Unknown tag identifiers return false rather than a name.
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
$result = exif_tagname(0x0112);
var_dump($result);Example 2: Another Case
Change the inputs to observe the behavior on another case.
<?php
$result = exif_tagname(0x010F);
var_dump($result);Practical Example
Use the result to create an output, validate a condition, or complete an image workflow.
<?php
$mapped = exif_tagname(0x010F);
if ($mapped === false) throw new RuntimeException("Unknown format or tag");
echo $mapped;For production, apply the compatibility and edge-case limits described below.
Important Behavior and Edge Cases
Unknown tag identifiers return false rather than a name.
Comparison with Related Functions and Tools
| Subject | Key difference |
|---|---|
| exif_tagname() | getimagesize() reads dimensions; EXIF functions inspect metadata or image signatures. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Calling exif_tagname() without its required input or supported extension | Check the extension, supply valid arguments, and handle false or exceptions according to the function. |
| Assuming exif_tagname() guarantees a valid or safe image | Unknown tag identifiers return false rather than a name. |
| Confusing the operation with a related API | getimagesize() reads dimensions; EXIF functions inspect metadata or image signatures. |
Key Takeaways
- Resolves a numeric EXIF tag identifier into its readable tag name.
- Unknown tag identifiers return false rather than a name.
- 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.