exif_imagetype

Opis

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.

Parametry

Zwracane wartości

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.

Rejestr zmian

Stałe predefinopwane

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

Przykłady

Przykład 1. exif_imagetype() example <?php if (exif_imagetype('image.gif') != IMAGETYPE_GIF) {     echo 'The picture is not a gif'; } ?>

Patrz także