Determine the type of an image

Description

int exif_imagetype ( string $filename )

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.

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
5.3.0	Added icon support.

Predefined Constants

The following constants are defined, and represent possible exif_imagetype() return values:

**Imagetype Constants**
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`

Examples

Example #1 exif_imagetype() example


<?php
if (exif_imagetype('image.gif') != IMAGETYPE_GIF) {
    echo 'The picture is not a gif';
}
?>