Laravel 5 imagepng not working - php

Question

I'm trying to create a script that takes a certain part of an image but when i use imagepng, it returns me this:
Here's my code
$name = $path;
header("Content-type: image/png");
if (strpos($name, '..') !== false) {
exit(); // name in path with '..' in it would allow for directory
traversal.
}
$size = $face_size > 0 ? $face_size : 100;
//Grab the skin
$src = imagecreatefrompng("./skins/" . $name . ".png");
//If no path was given or no image can be found, then create from default
if (!$src) {
$src = imagecreatefrompng("./skins/default.png");
}
//Start creating the image
list($w, $h) = getimagesize("./skins/" . $name . ".png");
$w = $w / 8;
$dest = imagecreatetruecolor($w, $w);
imagecopy($dest, $src, 0, 0, $w, $w, $w, $w); // copy the face
// Check to see if the helm is not all same color
$bg_color = imagecolorat($src, 0, 0);
$no_helm = true;
// Check if there's any helm
for ($i = 1; $i <= $w; $i++) {
for ($j = 1; $j <= 4; $j++) {
// scanning helm area
if (imagecolorat($src, 40 + $i, 7 + $j) != $bg_color) {
$no_helm = false;
}
}
if (!$no_helm)
break;
}
// copy the helm
if (!$no_helm) {
imagecopy($dest, $src, 0, -1, 40, 7, $w, 4);
}
//prepare to finish the image
$final = imagecreatetruecolor($size, $size);
imagecopyresized($final, $dest, 0, 0, 0, 0, $size, $size, $w, $w);
//if its not, just show image on screen
imagepng($final);
//Finally some cleanup
imagedestroy($dest);
imagedestroy($final);
I used this code previously without any framework and it worked just fine, I don't know where it comes from.

Answer 1

Laravel and other frameworks use Middlewares, so when your controller method is done the application isn't ready to send the response yet. You can solve the problem by storing the output of the imagepng function in an internal buffer and send it properly(I think there isn't another solution if you want to use GD), also you have to use Laravel's function to set the HTTP headers instead of the header function.
Here is a simple example:
namespace App\Http\Controllers;
use Illuminate\Http\Request;
class AppController extends Controller
{
//Generates an image with GD and sends it to the client.
public function image(){
$im = imagecreatetruecolor(800, 420);
$orange = imagecolorallocate($im, 220, 210, 60);
imagestring($im, 3, 10, 9, 'Example image', $orange);
//Turn on output buffering
ob_start();
imagepng($im);
//Store the contents of the output buffer
$buffer = ob_get_contents();
// Clean the output buffer and turn off output buffering
ob_end_clean();
imagedestroy($im);
return response($buffer, 200)->header('Content-type', 'image/png');
}
}
You can look at this, I hope it will help you.
Although it works, it isn't the best method, I recommend you to use Imagick(if you can) instead of GD.