PHP Manual: Get the size of an image

Description

array getimagesize ( string $filename [, array &$imageinfo ] )

The getimagesize function will determine the size of any given 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 and the correspondant HTTP content type.

getimagesize can also return some more information in imageinfo parameter.

Note: Note that JPC and JP2 are capable of having components with different bit depths. In this case, the value for "bits" is the highest bit depth encountered. Also, JP2 files may contain multiple JPEG 2000 codestreams. In this case, getimagesize returns the values for the first codestream it encounters in the root of the file.

Note: The information about icons are retrieved from the icon with the highest bitrate.

Parameters

filename: This parameter specifies the file you wish to retrieve information about. It can reference a local file or (configuration permitting) a remote file using one of the supported streams.
imageinfo: This optional 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 information in the APP13 marker. You can use the iptcparse function to parse the binary APP13 marker into something readable.

Return Values

Returns an array with up to 7 elements. Not all image types will include the channels and bits elements.

Index 0 and 1 contains respectively the width and the height of the image.

Note:
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.

Index 2 is one of the IMAGETYPE_XXX constants indicating the type of the image.

Index 3 is a text string with the correct height="yyy" width="xxx" string that can be used directly in an IMG tag.

mime is the correspondant MIME type of the image. This information can be used to deliver images with the correct HTTP Content-type header:

Example #1 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
}
?>

channels will be 3 for RGB pictures and 4 for CMYK pictures.

bits is the number of bits for each color.

For some image types, the presence of channels and bits 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.

On failure, FALSE is returned.

Errors/Exceptions

If accessing the filename image is impossible getimagesize will generate an error of level E_WARNING. On read error, getimagesize will generate an error of level E_NOTICE.

Changelog

Version	Description
5.3.0	Added icon support.
5.2.3	Read errors generated by this function downgraded to `E_NOTICE` from `E_WARNING`.
4.3.2	Support for JPC, JP2, JPX, JB2, XBM, and WBMP became available.
4.3.2	JPEG 2000 support was added for the `imageinfo` parameter.
4.3.0	bits and channels are present for other image types, too.
4.3.0	mime was added.
4.3.0	Support for SWC and IFF was added.
4.2.0	Support for TIFF was added.
4.0.6	Support for BMP and PSD was added.
4.0.5	URL support was added.

Examples

Example #2 getimagesize example


<?php
list($width, $height, $type, $attr) = getimagesize("img/flag.jpg");
echo "<img src=\"img/flag.jpg\" $attr alt=\"getimagesize() example\" />";
?>

Example #3 getimagesize (URL)


<?php
$size = getimagesize("http://www.example.com/gifs/logo.gif");

// if the file name has space in it, encode it properly
$size = getimagesize("http://www.example.com/gifs/lo%20go.gif");

?>

Example #4 getimagesize() returning IPTC


<?php
$size = getimagesize("testimg.jpg", $info);
if (isset($info["APP13"])) {
    $iptc = iptcparse($info["APP13"]);
    var_dump($iptc);
}
?>

Notes

Note:
This function does not require the GD image library.

getimagesize