exif_imagetype
exif_imagetype reads the first bytes of an image and checks its signature.
exif_imagetype can be used to avoid calls to other exif functions with unsupported file types or in conjunction with $_SERVER['HTTP_ACCEPT'] to check whether or not the viewer is able to see a specific image in the browser.
Parameters
- filename
-
The image being checked.
Return Values
When a correct signature is found, the appropriate constant value will be returned otherwise the return value is false. The return value is the same value that getimagesize returns in index 2 but exif_imagetype is much faster.
The following constants are defined, and represent possible exif_imagetype return values:
| Value | Constant |
| 1 | IMAGETYPE_GIF |
| 2 | IMAGETYPE_JPEG |
| 3 | IMAGETYPE_PNG |
| 4 | IMAGETYPE_SWF |
| 5 | IMAGETYPE_PSD |
| 6 | IMAGETYPE_BMP |
| 7 | IMAGETYPE_TIFF_II (intel byte order) |
| 8 | IMAGETYPE_TIFF_MM (motorola byte order) |
| 9 | IMAGETYPE_JPC |
| 10 | IMAGETYPE_JP2 |
| 11 | IMAGETYPE_JPX |
| 12 | IMAGETYPE_JB2 |
| 13 | IMAGETYPE_SWC |
| 14 | IMAGETYPE_IFF |
| 15 | IMAGETYPE_WBMP |
| 16 | IMAGETYPE_XBM |
| 17 | IMAGETYPE_ICO |
| 18 | IMAGETYPE_WEBP |
Note:
exif_imagetype will emit an E_NOTICE and return false if it is unable to read enough bytes from the file to determine the image type.
Changelog
| Version | Description |
| 7.1.0 | Added WebP support. |