PHP 5.2 — Как изменить размер изображения с помощью PHP, как удалить ошибку 500 Internal Server Error 817ms

$.ajax({
formData.append('file', $('input[type=file]')[0].files[0]);
url: 'file_check.php',
type: 'POST',
data: formData,
async: false,
cache: false,
contentType: false,
processData: false,
success: function (data) {
var res=jQuery.parseJSON(data);// convert the json
console.log(res);

},
});

file_check.php<?php
/*$extension = pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION);
$path = $_FILES['file']['tmp_name'];
$filename = file_get_contents($path);*/
/*
$imgdata = base64_encode($im); // here we got base64 encode value

$idproof = array("encode" => $imgdata,
"path" =>$path,
"extension" =>$extension,
);
echo json_encode($idproof);*/$image;
$image_type;

//-----------------------------------------------
//   Load Image file
//-----------------------------------------------
function load($filename)
{
global $image;
global $image_type;

$image_info = getimagesize($filename);
$image_type = $image_info[2];
if($image_type == IMAGETYPE_JPEG)
{
$image = imagecreatefromjpeg($filename);
}
elseif($image_type == IMAGETYPE_GIF)
{
$image = imagecreatefromgif($filename);
}
elseif($image_type == IMAGETYPE_PNG)
{
$image = imagecreatefrompng($filename);
}
}

//-----------------------------------------------
//   Save Image file
//-----------------------------------------------
function save($filename, $image_type=IMAGETYPE_JPEG, $compression=75, $permissions=null)
{
global $image;
global $image_type;

if( $image_type == IMAGETYPE_JPEG )
{
imagejpeg($image,$filename,$compression);
}
elseif( $image_type == IMAGETYPE_GIF )
{
imagegif($image,$filename);
}
elseif( $image_type == IMAGETYPE_PNG )
{
imagepng($image,$filename);
}
if( $permissions != null )
{
chmod($filename,$permissions);
}
}

//-----------------------------------------------
//   View Image file
//-----------------------------------------------
function output($image_type=IMAGETYPE_JPEG)
{
global $image;
global $image_type;

if( $image_type == IMAGETYPE_JPEG )
{
imagejpeg($image);
}
elseif( $image_type == IMAGETYPE_GIF )
{
imagegif($image);
} elseif( $image_type == IMAGETYPE_PNG )
{
imagepng($image);
}
}

function getWidth()
{
global $image;
return imagesx($image);
}
function getHeight()
{
global $image;
return imagesy($image);
}

//=============================================================================
//   Resize Images
//=============================================================================

//-----------------------------------------------
//   Resize Images 01 - Resize to Height
//-----------------------------------------------
function resizeToHeight($height)
{
$ratio = $height / getHeight();
$width = getWidth() * $ratio;
resize($width,$height);
}

//-----------------------------------------------
//   Resize Images 02 - Resize to Width
//-----------------------------------------------
function resizeToWidth($width)
{
$ratio = $width / getWidth();
$height = getheight() * $ratio;
resize($width,$height);
}

//-----------------------------------------------
//   Resize Images 03 - Scale in %
//-----------------------------------------------
function scale($scale)
{
$width = getWidth() * $scale/100;
$height = getheight() * $scale/100;
resize($width,$height);
}

//-----------------------------------------------
//   Resize Images 04 - Scale in %
//-----------------------------------------------
function resize($width,$height)
{
global $image;

$new_image = imagecreatetruecolor($width, $height);
imagecopyresampled($new_image, $image, 0, 0, 0, 0, $width, $height, getWidth(), getHeight());
$image = $new_image;
}echo load($_FILES['IMAGE_FILE']['tmp_name']);

// To resize based on image width
echo resizeToWidth($width);

// To resize based on image height
echo resizeToHeight($height);

// To resize to specific size
echo resize($width, $height)

echo output();

$filename = base64_encode(output());

$idproof = array("encode" => $filename,
);
echo json_encode($idproof);?>

<form method="post" enctype="multipart/form-data" class="form-horizontal" id="idproof" name="myForm">
<div class="input-group heading1">
<span class="input-group-btn">
<span class="btn btn-primary btn-file">
Browse&hellip; <input type="file" id="myFile" name="file" >
</span>
</span>
<input type="text" class="form-control" readonly="">
</div>
</div>
</div>
<div class="row">
<div class="col-md-5 col-md-offset-2">
<div class="input-group heading1">
<span class="input-group-btn">
<button type="submit" class="btn btn-primary btn-md horoscope">Upload ID Proof</button>
</div>
</div>
</div>
</form