Create a thumbnail from uploaded pdf - php

Question

I am trying to make a preview from pdf that users must to upload. I am using 1and1 hosting server, so I don´t have total control about what to install, and I don´t know how to install ImageMagick. I followed these steps and I was using this code (that is working in a different project using a VPS):
private function preViewPDF($filename)
{
$img_path = './assets/uploads/previews';
$file_name = explode(".", $filename)[0].".jpg";
$dir = './assets/upload/files/';
$img = new Imagick($dir."/".$filename.'[0]');
$img->setImageFormat('jpg');
$img->writeImage($img_path."/".$file_name);
return "previews/".$id.$type."/".$file_name;
}
After try that and get Imagick Class not Found Exception, I am trying to convert using exec command:
Actual code
private function preViewPDF($filename)
{
$file_name = explode(".", $filename)[0].".jpg";
$dir = getcwd().'/assets/uploads/files/';
if(file_exists($dir."/".$filename))
{
exec("convert ".$dir."/".$filename.'[0]'." ".$dir."/".$file_name, $output, $return_var);
var_dump($output);
echo "<br>";
var_dump($return_var);
}
else echo "no file";
echo "<br>".$dir."/".$filename.'[0]'."<br>";
echo "<br>".$file_name."<br>";
}
The var_dump($output); throws an empty array. And the $return_var is 1... general error :(
If I change the value between [] (the number of the page I want to convert) $output throws:
array(3) {
[0]=> string(0) ""
[1]=> string(70) "Requested FirstPage is greater than the number of pages in the file: 1"
[2]=> string(53) " No pages will be processed (FirstPage > LastPage)."
}
So... any ideas what am I doing wrong?? Thank you.
Extra Data
Only two little things more (maybe obvious). The first, if I emulate the order on a SSL connection it works (I get a image from a pdf). And second, permissions are not the reason (I tried to create and write a file -with fopen and fwrite- and it works).
EDIT
First, an explanation about my actual code:
$file_name = explode(".", $filename)[0].".jpg";
This line is because the extension of $filename is .pdf, so I need remove this part and concatenate the right extension .jpg (from hello.pdf I get hello.jpg).
$dir = getcwd().'/assets/uploads/files/';
This is the folder where the pdf is uploaded and the jpg preview must be saved.
if(file_exists($dir."/".$filename))
I put this line, simply because I though that the uploading of the pdf wasn´t finished and this was the reason that doesn´t work.
exec("convert ".$dir."/".$filename.'[0]'." ".$dir."/".$file_name, $output, $return_var);
This is the line where the command convert is executed... but doesn´t work.
Second thing is a new simple code I just tried:
if(file_exists("./DpRPJTmfSArPRuGZrOddLendfbhgHTrydwukMRvOMuSzVMDuBb.pdf"))
{
exec("convert ./DpRPJTmfSArPRuGZrOddLendfbhgHTrydwukMRvOMuSzVMDuBb.pdf[0] ./DpRPJTmfSArPRuGZrOddLendfbhgHTrydwukMRvOMuSzVMDuBb.jpg", $output, $return_var);
var_dump($output);
echo "<br>";
var_dump($return_var);
}
else echo "no hay fichero";
The $output is empty, and the $return_var is 1.

Answer 1

Forget all the dross and start simple with the file in the same folder as the code to see if Imagemagick is working.
convert input.pdf output.jpg
Also you have so many variables etc. in the Imagemagick code it is hard to read it.
I am also confused by your code and I would create the filename and path outside the convert code and you can echo it to ensure it contains what you expect.
This looks wrong:
$filename.'[0]'
I would try:
$filename[0]
I assume your pdf has more than one page?
Edit
Try this code - it has a different way of displaying any errors and allows you to view the contents of your command if you have lots of variables etc.
$error=array();
echo "<pre>";
$cmd = "./DpRPJTmfSArPRuGZrOddLendfbhgHTrydwukMRvOMuSzVMDuBb.pdf[0] ./DpRPJTmfSArPRuGZrOddLendfbhgHTrydwukMRvOMuSzVMDuBb.jpg";
// You can use this line to see what the $cmd ontains when using a lot of variables
echo $cmd;
exec("$cmd 2>&1", $error);
echo "<br>".print_r($error)."<br>";
echo "</pre>";

Answer 2

I make preview with this:
exec('convert -density 300 -trim "'.$file.'" -resize 600 -quality 85 -colorspace RGB -background white "'.$destination.'" &', $output, $return_var);
Where $file is tue original and $destination is the name of image.
With the & at the end, each image will be named image-0.jpg, image-1.jpg..
$return_var == 0 when all is OK