Image
If the function exif_imagetype() is not available,
you can try the following workaround:
if ( ! function_exists( 'exif_imagetype' ) ) {
function exif_imagetype ( $filename ) {
if ( ( list($width, $height, $type, $attr) = getimagesize( $filename ) ) !== false ) {
return $type;
}
return false;
}
}
exif_imagetype
Description
int exif_imagetype ( string filename)exif_imagetype() reads the first bytes of an image and checks its signature. When a correct signature is found a constant 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.
The following constants are defined:
Tablo 1. 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 |
Not: 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 $_SERVER['HTTP_ACCEPT'] to check whether or not the viewer is able to see a specific image in the browser.
Not: This function is only available if PHP is compiled using --enable-exif.
Not: This function does not require the GD image library.
See also getimagesize().
add a note
User Contributed Notesexif_imagetype
tom dot ghyselinck at telenet dot be
13-Jan-2008 01:36
13-Jan-2008 01:36
Tim
19-Nov-2007 08:40
19-Nov-2007 08:40
By trial and error, it seems that a file has to be 12 bytes or larger in order to avoid a "Read error!". Here's a work-around to avoid an error being thrown:
// exif_imagetype throws "Read error!" if file is too small
if (filesize($uploadfile) > 11)
$mimetype = exif_imagetype($uploadfile);
else
$mimetype = false;
09-Nov-2006 04:43
Seems to give a 'Read error' warning if the size of the file is very small (2 bytes). I think this is because it needs a min 3 bytes to determine the file type
tom at tomvergote dot be
07-Feb-2004 02:11
07-Feb-2004 02:11
libexif can also be used to parse image info out of id3 tags:
exif_read_data("mp3_with_2.4ID3TAGS, '', true, false);
tilmauder at yahoo dot com
05-Jul-2003 04:57
05-Jul-2003 04:57
After looking for hours, I found a very good source for exif related programs here: http://drewnoakes.com/code/exif/index.html
It lists exif specifications (pdf), a few good links to exif related stuff. The best source I have found in my quest to understand exif better for use in php based exif tools.