I am running Drupal 7.56

I have been using Views extensively for some months now. I want now to create custom pdf pages from some Views.

I have installed jQuery_update, then Views PDF Display Module, then copied fpdi and tcpdf libraries into the Libraries folder (via FTP).

I can now add a PDF Page to a View, but when I click it, I get the following error message :
Fatal error: Class 'setasign\Fpdi\FpdfTpl' not found in /home/my_hostname/www/www/sites/all/libraries/fpdi/fpdi.php on line 25

I suspect that this is due to a bad installation, but find no clear and up-to-date installation tutorial.

I must say that I am not a programmer.
Any help is welcome