(PHP 4 >= 4.2.0, PHP 5)
exif_tagname — Get the header name for an index
$index
)
index
The Tag ID for which a Tag Name will be looked up.
Returns the header name, or FALSE if index is
not a defined EXIF tag id.
Example #1 exif_tagname() example
<?php
echo "256: ".exif_tagname(256).PHP_EOL;
echo "257: ".exif_tagname(257).PHP_EOL;
?>
以上例程会输出：
256: ImageWidth 257: ImageLength
abc at ed48 dot com (2011-06-22 10:03:02)
In association with exif_read_data:
<?php
# The tagnames can vary in different cameras
$imgdir = "/path_to_img/";
$img_file = "image_file.jpg";
echo $img_file . " <sub>TEST</sub>
<br />";
echo '<img src="' . $imgdir . $img_file . '" alt="'
. $img_file . '" title="' . $img_file . '" width="400" /><br /><br />';
$xf_data = exif_read_data($imgdir . $img_file);
$tagg = exif_tagname(0X10F);
echo '<br>' . $tagg . ' >>> ' . $xf_data[$tagg];
$tagg = exif_tagname(0X110);
echo '<br>' . $tagg . ' >>> ' . $xf_data[$tagg];
$tagg = exif_tagname(0X132);
echo '<br>' . $tagg . ' >>> ' . $xf_data[$tagg];
$tagg = exif_tagname(0XA002);
echo '<br>' . $tagg . ' >>> ' . $xf_data[$tagg] . 'px';
$tagg = exif_tagname(0XA003);
echo '<br>' . $tagg . ' >>> ' . $xf_data[$tagg] . 'px';
?>
abc at ed48 dot com (2011-06-21 13:20:50)
Theoretically, 65,535 tags are possible. Although not all are used, yet. The code below lists these tags:
<?php
for ($id = 1; $id <= 65535; $id++)
{
$dec2hex = dechex($id);
$strgx = '0x'. $dec2hex;
if(exif_tagname($strgx) != "")
{
echo $strgx . ' ( ' . exif_tagname($strgx) . ' )<br />';
}
}
?>
djmaze@moocms (2008-02-22 17:23:14)
Usage: exif_tagname(0x5001)
A list of all supported index numbers is in the exif.c: tag_table_IFD
http://cvs.php.net/viewvc.cgi/php-src/ext/exif/exif.c?view=markup
As you can see, it doesn't support them all!