Resizing picture with PHP?

Question

I need to resize a picture to a fixed size. But it doesn't work and have error, what do i do?

ONLINE DEMO: http://codepad.org/3OrIHfoy

ERROR:

Fatal error: Call to undefined function imagecreatefromjpeg() on line 58

PHP:

<?php
function thumbnail_box($img, $box_w, $box_h) {
    //create the image, of the required size
    $new = imagecreatetruecolor($box_w, $box_h);
    if($new === false) {
        //creation failed -- probably not enough memory
        return null;
    }


    //Fill the image with a light grey color
    //(this will be visible in the padding around the image,
    //if the aspect ratios of the image and the thumbnail do not match)
    //Replace this with any color you want, or comment it out for black.
    //I used grey for testing =)
    $fill = imagecolorallocate($new, 200, 200, 205);
    imagefill($new, 0, 0, $fill);

    //compute resize ratio
    $hratio = $box_h / imagesy($img);
    $wratio = $box_w / imagesx($img);
    $ratio = min($hratio, $wratio);

    //if the source is smaller than the thumbnail size, 
    //don't resize -- add a margin instead
    //(that is, dont magnify images)
    if($ratio > 1.0)
        $ratio = 1.0;

    //compute sizes
    $sy = floor(imagesy($img) * $ratio);
    $sx = floor(imagesx($img) * $ratio);

    //compute margins
    //Using these margins centers the image in the thumbnail.
    //If you always want the image to the top left, 
    //set both of these to 0
    $m_y = floor(($box_h - $sy) / 2);
    $m_x = floor(($box_w - $sx) / 2);

    //Copy the image data, and resample
    //
    //If you want a fast and ugly thumbnail,
    //replace imagecopyresampled with imagecopyresized
    if(!imagecopyresampled($new, $img,
        $m_x, $m_y, //dest x, y (margins)
        0, 0, //src x, y (0,0 means top left)
        $sx, $sy,//dest w, h (resample to this size (computed above)
        imagesx($img), imagesy($img)) //src w, h (the full size of the original)
    ) {
        //copy failed
        imagedestroy($new);
        return null;
    }
    //copy successful
    return $new;
}
$i = imagecreatefromjpeg("http://techstroke.com/wp-content/uploads/2008/12/image2.png");
$thumb = thumbnail_box($i, 210, 150);
imagedestroy($i);

if(is_null($thumb)) {
    /* image creation or copying failed */
    header('HTTP/1.1 500 Internal Server Error');
    exit();
}
header('Content-Type: image/jpeg');
imagejpeg($thumb);

I like that you're trying to use imagecreatefrom**jpeg** to load a PNG. Good times. Either way it looks like you don't have the php5-gd package installed for your distribution. — Sean Bright, Feb 11 '14 at 22:46

score 0 · Accepted Answer · answered Feb 11 '14 at 23:03

that error...

Fatal error: Call to undefined function imagecreatefromjpeg() on line 58

imagecreatefromjpeg() is not callable because it does not exist. This means that the GD library has yet to be installed on your system.

here are the installation notes. you'll need them to get everything going. since you snagged that php function off the internet, it should work okay once you get the GD library installed.

Resizing picture with PHP?

1 Answers1