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Redimensionner les images avec PHP, prendre en charge PNG, JPG

J'utilise cette classe:

class ImgResizer {

function ImgResizer($originalFile = '$newName') {
    $this -> originalFile = $originalFile;
}
function resize($newWidth, $targetFile) {
    if (empty($newWidth) || empty($targetFile)) {
        return false;
    }
    $src = imagecreatefromjpeg($this -> originalFile);
    list($width, $height) = getimagesize($this -> originalFile);
    $newHeight = ($height / $width) * $newWidth;
    $tmp = imagecreatetruecolor($newWidth, $newHeight);
    imagecopyresampled($tmp, $src, 0, 0, 0, 0, $newWidth, $newHeight, $width, $height);

    if (file_exists($targetFile)) {
        unlink($targetFile);
    }
    imagejpeg($tmp, $targetFile, 95);
}

}

Ce qui fonctionne parfaitement, mais il échoue avec les png, il crée une image noire redimensionnée.

Existe-t-il un moyen de modifier cette classe pour prendre en charge les images png?

phpimageresizepng
19
Toni Michel Caubet
function resize($newWidth, $targetFile, $originalFile) {

    $info = getimagesize($originalFile);
    $mime = $info['mime'];

    switch ($mime) {
            case 'image/jpeg':
                    $image_create_func = 'imagecreatefromjpeg';
                    $image_save_func = 'imagejpeg';
                    $new_image_ext = 'jpg';
                    break;

            case 'image/png':
                    $image_create_func = 'imagecreatefrompng';
                    $image_save_func = 'imagepng';
                    $new_image_ext = 'png';
                    break;

            case 'image/gif':
                    $image_create_func = 'imagecreatefromgif';
                    $image_save_func = 'imagegif';
                    $new_image_ext = 'gif';
                    break;

            default: 
                    throw new Exception('Unknown image type.');
    }

    $img = $image_create_func($originalFile);
    list($width, $height) = getimagesize($originalFile);

    $newHeight = ($height / $width) * $newWidth;
    $tmp = imagecreatetruecolor($newWidth, $newHeight);
    imagecopyresampled($tmp, $img, 0, 0, 0, 0, $newWidth, $newHeight, $width, $height);

    if (file_exists($targetFile)) {
            unlink($targetFile);
    }
    $image_save_func($tmp, "$targetFile.$new_image_ext");
}
44
P. Galbraith

J'ai écrit un cours qui fera exactement cela et qui est agréable et facile à utiliser. C'est appelé
PHP Image Magician

$magicianObj = new imageLib('racecar.jpg');
$magicianObj -> resizeImage(100, 200);
$magicianObj -> saveImage('racecar_convertd.png', 100);

Il prend en charge la lecture et l'écriture (y compris la conversion) des formats suivants

  • jpg
  • png
  • gif
  • bmp

Et ne peut lire que

  • psd

Exemple 

// Include PHP Image Magician library
require_once('php_image_magician.php');

// Open JPG image
$magicianObj = new imageLib('racecar.jpg');

// Resize to best fit then crop
$magicianObj -> resizeImage(100, 200, 'crop');

// Save resized image as a PNG
$magicianObj -> saveImage('racecar_small.png');
12
Jarrod

Vous pouvez essayer ça. Actuellement, cela suppose que l'image sera toujours un JPEG. Cela vous permettra de charger un fichier jpeg, png ou gif. Je n'ai pas testé mais ça devrait marcher.

function resize($newWidth, $targetFile) {
    if (empty($newWidth) || empty($targetFile)) {
        return false;
    }

    $fileHandle = @fopen($this->originalFile, 'r');

    //error loading file
    if(!$fileHandle) {
        return false;
    }

    $src = imagecreatefromstring(stream_get_contents($fileHandle));

    fclose($fileHandle);

    //error with loading file as image resource
    if(!$src) {
        return false;
    }

    //get image size from $src handle
    list($width, $height) = array(imagesx($src), imagesy($src));

    $newHeight = ($height / $width) * $newWidth;

    $tmp = imagecreatetruecolor($newWidth, $newHeight);

    imagecopyresampled($tmp, $src, 0, 0, 0, 0, $newWidth, $newHeight, $width, $height);

    //allow transparency for pngs
    imagealphablending($tmp, false);
    imagesavealpha($tmp, true);

    if (file_exists($targetFile)) {
        unlink($targetFile);
    }

    //handle different image types.
    //imagepng() uses quality 0-9
    switch(strtolower(pathinfo($this->originalFile, PATHINFO_EXTENSION))) {
        case 'jpg':
        case 'jpeg':
            imagejpeg($tmp, $targetFile, 95);
            break;
        case 'png':
            imagepng($tmp, $targetFile, 8.5);
            break;
        case 'gif':
            imagegif($tmp, $targetFile);
            break;
    }

    //destroy image resources
    imagedestroy($tmp);
    imagedestroy($src);
}
7
Austin Brunkhorst

J'ai pris la version de P. Galbraith, corrigé les erreurs et l'ai changé pour redimensionner par zone (largeur x hauteur). Pour ma part, je voulais redimensionner des images trop grandes.

function resizeByArea($originalFile,$targetFile){

    $newArea = 375000; //a little more than 720 x 480

    list($width,$height,$type) = getimagesize($originalFile);
    $area = $width * $height;

if($area > $newArea){

    if($width > $height){ $big = $width; $small = $height; }
    if($width < $height){ $big = $height; $small = $width; }

    $ratio = $big / $small;

    $newSmall = sqrt(($newArea*$small)/$big);
    $newBig = $ratio*$newSmall;

    if($width > $height){ $newWidth = round($newBig, 0); $newHeight = round($newSmall, 0); }
    if($width < $height){ $newWidth = round($newSmall, 0); $newHeight = round($newBig, 0); }

    }

switch ($type) {
    case '2':
            $image_create_func = 'imagecreatefromjpeg';
            $image_save_func = 'imagejpeg';
            $new_image_ext = '.jpg';
            break;

    case '3':
            $image_create_func = 'imagecreatefrompng';
         // $image_save_func = 'imagepng';
         // The quality is too high with "imagepng"
         // but you need it if you want to allow transparency
            $image_save_func = 'imagejpeg';
            $new_image_ext = '.png';
            break;

    case '1':
            $image_create_func = 'imagecreatefromgif';
            $image_save_func = 'imagegif';
            $new_image_ext = '.gif';
            break;

    default: 
            throw Exception('Unknown image type.');
}

    $img = $image_create_func($originalFile);
    $tmp = imagecreatetruecolor($newWidth,$newHeight);
    imagecopyresampled( $tmp, $img, 0, 0, 0, 0,$newWidth,$newHeight, $width, $height );

    ob_start();
    $image_save_func($tmp);
    $i = ob_get_clean();

    // if file exists, create a new one with "1" at the end
    if (file_exists($targetFile.$new_image_ext)){
      $targetFile = $targetFile."1".$new_image_ext;
    }
    else{
      $targetFile = $targetFile.$new_image_ext;
    }

    $fp = fopen ($targetFile,'w');
    fwrite ($fp, $i);
    fclose ($fp);

    unlink($originalFile);
}

Si vous souhaitez autoriser la transparence, vérifiez ceci: http://www.akemapa.com/2008/07/10/php-Gd-resize-transparent-image-png-gif/

J'ai testé la fonction, ça marche bien!

1
pmrotule

Essayez celui-ci et en utilisant cela, vous pouvez également enregistrer votre image dans un chemin spécifique.

function resize($file, $imgpath, $width, $height){
    /* Get original image x y*/
    list($w, $h) = getimagesize($file['tmp_name']);
    /* calculate new image size with ratio */
    $ratio = max($width/$w, $height/$h);
    $h = ceil($height / $ratio);
    $x = ($w - $width / $ratio) / 2;
    $w = ceil($width / $ratio);

    /* new file name */
    $path = $imgpath;
    /* read binary data from image file */
    $imgString = file_get_contents($file['tmp_name']);
    /* create image from string */
    $image = imagecreatefromstring($imgString);
    $tmp = imagecreatetruecolor($width, $height);
    imagecopyresampled($tmp, $image, 0, 0, $x, 0, $width, $height, $w, $h);
    /* Save image */
    switch ($file['type']) {
       case 'image/jpeg':
          imagejpeg($tmp, $path, 100);
          break;
       case 'image/png':
          imagepng($tmp, $path, 0);
          break;
       case 'image/gif':
          imagegif($tmp, $path);
          break;
          default:
          //exit;
          break;
        }
     return $path;

     /* cleanup memory */
     imagedestroy($image);
     imagedestroy($tmp);
}

Maintenant, vous devez appeler cette fonction tout en enregistrant l'image comme ...

<?php

    //$imgpath = "Where you want to save your image";
    resize($_FILES["image"], $imgpath, 340, 340);

?>
1
Hardik

la réponse acceptée a beaucoup d'erreurs ici est-elle fixée

<?php 




function resize($newWidth, $targetFile, $originalFile) {

    $info = getimagesize($originalFile);
    $mime = $info['mime'];

    switch ($mime) {
            case 'image/jpeg':
                    $image_create_func = 'imagecreatefromjpeg';
                    $image_save_func = 'imagejpeg';
                    $new_image_ext = 'jpg';
                    break;

            case 'image/png':
                    $image_create_func = 'imagecreatefrompng';
                    $image_save_func = 'imagepng';
                    $new_image_ext = 'png';
                    break;

            case 'image/gif':
                    $image_create_func = 'imagecreatefromgif';
                    $image_save_func = 'imagegif';
                    $new_image_ext = 'gif';
                    break;

            default: 
                    throw Exception('Unknown image type.');
    }

    $img = $image_create_func($originalFile);
    list($width, $height) = getimagesize($originalFile);
    $newHeight = ($height / $width) * $newWidth;
    $tmp = imagecreatetruecolor($newWidth, $newHeight);
    imagecopyresampled($tmp, $img, 0, 0, 0, 0, $newWidth, $newHeight, $width, $height);

    if (file_exists($targetFile)) {
            unlink($targetFile);
    }
    $image_save_func($tmp, "$targetFile.$new_image_ext");
}



$img=$_REQUEST['img'];
$id=$_REQUEST['id'];

  //  echo $img
resize(120, $_SERVER['DOCUMENT_ROOT'] ."/images/$id",$_SERVER['DOCUMENT_ROOT'] ."/images/$img") ;


?>
0
bdaz