imagecreatefromjpeg
(PHP 4, PHP 5)
imagecreatefromjpeg — Create a new image from file or URL
Description
imagecreatefromjpeg() returns an image identifier representing the image obtained from the given filename.
On failure imagecreatefromjpeg() outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error JPEG:
Example#1 Example to handle an error during creation
<?php
function LoadJpeg($imgname)
{
$im = @imagecreatefromjpeg($imgname); /* Attempt to open */
if (!$im) { /* See if it failed */
$im = imagecreatetruecolor(150, 30); /* Create a black image */
$bgc = imagecolorallocate($im, 255, 255, 255);
$tc = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 150, 30, $bgc);
/* Output an errmsg */
imagestring($im, 1, 5, 5, "Error loading $imgname", $tc);
}
return $im;
}
header("Content-Type: image/jpeg");
$img = LoadJpeg("bogus.image");
imagejpeg($img);
?>
The above example will output something similar to:

如果 fopen wrappers 已啟動,則可藉此函數把檔名當成URL使用。參考 fopen() 有更多關於如何指定檔名的細節和List of Supported Protocols/Wrappers支援URL協定的列表。
Parameters
- filename
-
Path to the JPEG image
Return Values
Returns an image resource identifier on success, FALSE on errors.
Notes
Note: JPEG support is only available if PHP was compiled against GD-1.8 or later.
PHP 4.3.0 之前的 Windows PHP版本不支援由此函數存取遠端檔案,即使啟動allow_url_fopen選項。