Description
array
getimagesize ( string filename [, array imageinfo])
The getimagesize() function will determine the
size of any GIF, JPG,
PNG, SWF,
SWC, PSD,
TIFF, BMP or
IFF
image file and return the dimensions along with the file type and
a height/width text string to be used inside a normal
HTML IMG tag.
Returns an array with 4 elements. Index 0 contains the width of
the image in pixels. Index 1 contains the height. Index 2 is a
flag indicating the type of the image: 1 = GIF, 2 = JPG, 3 =
PNG, 4 = SWF, 5 = PSD, 6 = BMP, 7 = TIFF(intel byte order),
8 = TIFF(motorola byte order), 9 = JPC, 10 = JP2, 11 = JPX, 12 =
JB2, 13 = SWC, 14 = IFF. These values correspond to the IMAGETYPE
constants that were added in PHP 4.3. Index 3 is a text string with
the correct height="yyy" width="xxx" string that can be used
directly in an IMG tag.
Example 1. getimagesize (file) <?php
$size = getimagesize ("img/flag.jpg");
echo "<img src=\"img/flag.jpg\" {$size[3]}>";
?> |
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Example 2. getimagesize (URL) <?php $size = getimagesize ("http://www.example.com/gifs/logo.gif"); ?> |
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With JPG images, two extra indexes are returned:
channels and bits.
channels will be 3 for RGB pictures and 4 for CMYK
pictures. bits is the number of bits for each color.
Beginning with PHP 4.3, bits and
channels are present for other image types, too.
However, the presence of these values can be a bit confusing. As an
example, GIF always uses 3 channels per pixel, but the
number of bits per pixel cannot be calculated for an animated
GIF with a global color table.
Some formats may contain no image or may contain multiple images. In these
cases, getimagesize() might not be able to properly
determine the image size. getimagesize() will return
zero for width and height in these cases.
Beginning with PHP 4.3, getimagesize() also returns an
additional parameter, mime, that corresponds with the
MIME type of the image. This information can be used to deliver images
with correct HTTP Content-type headers:
Example 3. getimagesize() and MIME types <?php
$size = getimagesize ($filename);
$fp=fopen($filename, "rb");
if ($size && $fp) {
header("Content-type: {$size['mime']}");
fpassthru($fp);
exit;
} else {
// error
}
?> |
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If accessing the filename image is impossible,
or if it isn't a valid picture, getimagesize()
will return FALSE and generate a warning.
The optional imageinfo parameter allows
you to extract some extended information from the image
file. Currently, this will return the different
JPG APP markers as an associative array. Some
programs use these APP markers to embed text information in
images. A very common one is to embed IPTC
http://www.iptc.org/ information in the
APP13 marker. You can use the iptcparse()
function to parse the binary APP13 marker into something
readable.
Example 4. getimagesize() returning IPTC <?php
$size = getimagesize ("testimg.jpg",&$info);
if (isset ($info["APP13"])) {
$iptc = iptcparse ($info["APP13"]);
var_dump ($iptc);
}
?> |
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