<?php// require composer autoloadrequire__DIR__.'/vendor/autoload.php';$mpdf=new\Mpdf\Mpdf(['format'=>'A4-L','margin_left'=>0,'margin_right'=>0,'margin_top'=>0,'margin_bottom'=>0,'margin_header'=>0,'margin_footer'=>0,]);$mpdf->SetImportUse();// only with mPDF <8.0$ow=$mpdf->h;$oh=$mpdf->w;$pw=$mpdf->w/2;$ph=$mpdf->h;$mpdf->SetDisplayMode('fullpage');$pagecount=$mpdf->SetSourceFile('A4sourcefile.pdf');$pp=GetBookletPages($pagecount);foreach($ppas$v){$mpdf->AddPage();if($v[0]>0&&$v[0]<=$pagecount){$tplIdx=$mpdf->ImportPage($v[0],0,0,$ow,$oh);$mpdf->UseTemplate($tplIdx,0,0,$pw,$ph);}if($v[1]>0&&$v[1]<=$pagecount){$tplIdx=$mpdf->ImportPage($v[1],0,0,$ow,$oh);$mpdf->UseTemplate($tplIdx,$pw,0,$pw,$ph);}}$mpdf->Output();exit;functionGetBookletPages($np,$backcover=true){$lastpage=$np;$np=4*ceil($np/4);$pp=[];for($i=1;$i<=$np/2;$i++){$p1=$np-$i+1;if($backcover){if($i==1){$p1=$lastpage;}elseif($p1>=$lastpage){$p1=0;}}$pp[]=($i%2==1)?[$p1,$i]:[$i,$p1];}return$pp;}