exif_imagetype

(PHP 4 >= 4.3.0, PHP 5)

exif_imagetype -- Determine the type of an image

Beskrivelse

int exif_imagetype ( string filename)

exif_imagetype() reads the first bytes of an image and checks its signature.

Bemærk: Support for JPC, JP2, JPX, JB2, XBM, and WBMP became available in PHP 4.3.2. Support for SWC as of PHP 4.3.0.

This function 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.

Foruddefinerede Konstanter

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

Tabel 1. Imagetype Constants

ValueConstant
1IMAGETYPE_GIF
2IMAGETYPE_JPEG
3IMAGETYPE_PNG
4IMAGETYPE_SWF
5IMAGETYPE_PSD
6IMAGETYPE_BMP
7IMAGETYPE_TIFF_II (intel byte order)
8 IMAGETYPE_TIFF_MM (motorola byte order)
9IMAGETYPE_JPC
10IMAGETYPE_JP2
11IMAGETYPE_JPX
12IMAGETYPE_JB2
13IMAGETYPE_SWC
14IMAGETYPE_IFF
15IMAGETYPE_WBMP
16IMAGETYPE_XBM

Returneringsværdier

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 this function is much faster.

Eksempler

Eksempel 1. exif_imagetype() example

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

Se også

getimagesize()