Créer une image à partir de l'URL de tout type de fichier
Je connais (imagecreatefromgif() } _, imagecreatefromjpeg() et imagecreatefrompng() , mais existe-t-il un moyen de créer une ressource image (pour png de préférence) à partir d'une URL de any type d'image valide? Ou devez-vous déterminer le type de fichier, puis utiliser la fonction appropriée?
Quand je dis URL, je veux dire quelque chose comme http://sample.com/image.png, pas une URL de données
Peut-être que vous voulez ceci:
$jpeg_image = imagecreatefromfile( 'photo.jpeg' );
$gif_image = imagecreatefromfile( 'clipart.gif' );
$png_image = imagecreatefromfile( 'transparent_checkerboard.PnG' );
$another_jpeg = imagecreatefromfile( 'picture.JPG' );
// This requires you to remove or rewrite file_exists check:
$jpeg_image = imagecreatefromfile( 'http://example.net/photo.jpeg' );
// SEE BELOW HO TO DO IT WHEN http:// ARGS IS NEEDED:
$jpeg_image = imagecreatefromfile( 'http://example.net/photo.jpeg?foo=hello&bar=world' );
Voici comment c'est fait:
function imagecreatefromfile( $filename ) {
if (!file_exists($filename)) {
throw new InvalidArgumentException('File "'.$filename.'" not found.');
}
switch ( strtolower( pathinfo( $filename, PATHINFO_EXTENSION ))) {
case 'jpeg':
case 'jpg':
return imagecreatefromjpeg($filename);
break;
case 'png':
return imagecreatefrompng($filename);
break;
case 'gif':
return imagecreatefromgif($filename);
break;
default:
throw new InvalidArgumentException('File "'.$filename.'" is not valid jpg, png or gif image.');
break;
}
}
Avec quelques petites modifications à switch, la même fonction est prête pour les URL Web:
/* if (!file_exists($filename)) {
throw new InvalidArgumentException('File "'.$filename.'" not found.');
} <== This needs addiotional checks if using non local picture */
switch ( strtolower( array_pop( explode('.', substr($filename, 0, strpos($filename, '?'))))) ) {
case 'jpeg':
Après cela, vous pouvez l'utiliser avec http://www.tld/image.jpg:
$jpeg_image = imagecreatefromfile( 'http://example.net/photo.jpeg' );
$gif_image = imagecreatefromfile( 'http://www.example.com/art.gif?param=23&another=yes' );
Quelques preuves:
Comme vous pouvez le lire dans le manuel officiel PHP function.imagecreatefromjpeg.php Gd permet de charger des images à partir d'URL prises en charge par function.fopen.php . pas besoin d'aller chercher l'image en premier et enregistrez-le dans un fichier et ouvrez ce fichier.
Le moyen le plus simple de le faire est de laisser php décider du type de fichier:
$image = imagecreatefromstring(file_get_contents($src));
J'utilise cette fonction. Il supporte tous les types d'URL et les wrappers de flux et tous les types d'images que php peut gérer.
/**
* creates a image ressource from file (or url)
*
* @version: 1.1 (2014-05-02)
*
* $param string: $filename url or local path to image file
* @param [bool: $use_include_path] As of PHP 5 the FILE_USE_INCLUDE_PATH constant can be used to trigger include path search.
* @param [resource: $context] A valid context resource created with stream_context_create(). If you don't need to use a custom context, you can skip this parameter by NULL
* @param [&array: $info] Array with result info: $info["image"] = imageinformation from getimagesize, $info["http"] = http_response_headers (if array was populated)
*
* @see: http://php.net/manual/function.file-get-contents.php
* @see: http://php.net/manual/function.getimagesize.php
*
* @return bool|resource<Gd> false, wenn aus Dateiinhalt keine gueltige PHP-Bildresource erstellt werden konnte (z.b. bei BMP-Datei)
* @throws InvalidArgumentException Wenn Datei kein gueltiges Bild ist, oder nicht gelesen werden kann
*
*/
function createImageFromFile($filename, $use_include_path = false, $context = null, &$info = null)
{
// try to detect image informations -> info is false if image was not readable or is no php supported image format (a check for "is_readable" or fileextension is no longer needed)
$info = array("image"=>getimagesize($filename));
$info["image"] = getimagesize($filename);
if($info["image"] === false) throw new InvalidArgumentException("\"".$filename."\" is not readable or no php supported format");
else
{
// fetches fileconten from url and creates an image ressource by string data
// if file is not readable or not supportet by imagecreate FALSE will be returnes as $imageRes
$imageRes = imagecreatefromstring(file_get_contents($filename, $use_include_path, $context));
// export $http_response_header to have this info outside of this function
if(isset($http_response_header)) $info["http"] = $http_response_header;
return $imageRes;
}
}
Utilisation (exemple simple):
$image = createImageFromFile("http://sample.com/image.png");
Utilisation (exemple complexe):
// even sources with php extensions are supported and e.g. Proxy connections and other context Options
// see http://php.net/manual/function.stream-context-create.php for examples
$options = array("http"=>
array("proxy" => "tcp://myproxy:8080",
"request_fulluri" => true
)
);
$context = stream_context_create($options);
$image = createImageFromFile("http://de3.php.net/images/logo.php", null, $context,$info);
// ... your code to resize or modify the image
Cela peut vous aider
$ image = imagecreatefromstring (file_get_contents ('votre chemin_image_ici'));
Exemple: $image = imagecreatefromstring(file_get_contents('sample.jpg'));
Commencez par récupérer l'URL à l'aide de la fonction file_get_contents($url) et enregistrez le contenu dans un fichier. Après cela, vous pouvez utiliser les fonctions de manipulation d’image appropriées pour effectuer d’autres modifications. Vous pouvez utiliser le code suivant pour enregistrer l'image à partir de l'URL. Voici l exemple de code:
$url = "http://sample.com/image.png";
$arr = explode("/",$url);
$img_file = dir(__FILE__).'/'.$arr[count($arr)-1];
$data = file_get_contents($url);
$fp = fopen($img_file,"w");
fwrite($fp,$data);
fclose($fp);
Merci.
vous analysez ce code.
$url=$_SERVER['REQUEST_URI'];
$url=explode('.',$url);
$extension=$url[1];
switch($extension){
case'jpg':
imagecreatefromjpeg();
break;
}
Vous pourriez aussi être intéressé par la version la plus avancée:
http://salman-w.blogspot.com/2008/10/resize-using-phpgd-library.html
<?php
/*
* PHP function to resize an image maintaining aspect ratio
* http://salman-w.blogspot.com/2008/10/resize-images-using-phpgd-library.html
*
* Creates a resized (e.g. thumbnail, small, medium, large)
* version of an image file and saves it as another file
*/
define('THUMBNAIL_IMAGE_MAX_WIDTH', 150);
define('THUMBNAIL_IMAGE_MAX_HEIGHT', 150);
function generate_image_thumbnail($source_image_path, $thumbnail_image_path)
{
list($source_image_width, $source_image_height, $source_image_type) = getimagesize($source_image_path);
switch ($source_image_type) {
case IMAGETYPE_GIF:
$source_Gd_image = imagecreatefromgif($source_image_path);
break;
case IMAGETYPE_JPEG:
$source_Gd_image = imagecreatefromjpeg($source_image_path);
break;
case IMAGETYPE_PNG:
$source_Gd_image = imagecreatefrompng($source_image_path);
break;
}
if ($source_Gd_image === false) {
return false;
}
$source_aspect_ratio = $source_image_width / $source_image_height;
$thumbnail_aspect_ratio = THUMBNAIL_IMAGE_MAX_WIDTH / THUMBNAIL_IMAGE_MAX_HEIGHT;
if ($source_image_width <= THUMBNAIL_IMAGE_MAX_WIDTH && $source_image_height <= THUMBNAIL_IMAGE_MAX_HEIGHT) {
$thumbnail_image_width = $source_image_width;
$thumbnail_image_height = $source_image_height;
} elseif ($thumbnail_aspect_ratio > $source_aspect_ratio) {
$thumbnail_image_width = (int) (THUMBNAIL_IMAGE_MAX_HEIGHT * $source_aspect_ratio);
$thumbnail_image_height = THUMBNAIL_IMAGE_MAX_HEIGHT;
} else {
$thumbnail_image_width = THUMBNAIL_IMAGE_MAX_WIDTH;
$thumbnail_image_height = (int) (THUMBNAIL_IMAGE_MAX_WIDTH / $source_aspect_ratio);
}
$thumbnail_Gd_image = imagecreatetruecolor($thumbnail_image_width, $thumbnail_image_height);
imagecopyresampled($thumbnail_Gd_image, $source_Gd_image, 0, 0, 0, 0, $thumbnail_image_width, $thumbnail_image_height, $source_image_width, $source_image_height);
imagejpeg($thumbnail_Gd_image, $thumbnail_image_path, 90);
imagedestroy($source_Gd_image);
imagedestroy($thumbnail_Gd_image);
return true;
}
?>