php generate thumbnail image_php generate thumbnail image code_PHP tutorial

php generate thumbnail image_php generate thumbnail image code This is a classic and practical PHP code for generating thumbnails. In professional terms, it is PHP code for generating thumbnails.

php tutorial to generate thumbnails_php generate thumbnail code
This is a classic and practical PHP code for generating thumbnails. In professional terms, it is PHP code for generating thumbnails.
*/

# Display graphics and connections

function showdir ($adirectory, $i)

{
global $browsedir;

$start = $i;

# Change $maxcols and $maximages to change the number of rows and columns of small images displayed on each page.

$maxcols = 2;
$maximages = 6;
$maximages = $i + ($maximages - 3);

# Change $imagemaxwidth and $imagemaxheight to change the width and height of the displayed thumbnail.

$imagemaxwidth = 100;
$imagemaxheight = 100;
 
# Calculate the ratio of height to width.

$imagemaxratio = $imagemaxwidth / $imagemaxheight;
 
$ndirectory = sizeof ($adirectory);
echo (table_start);
for ($i; $i<=$maximages;)
{
echo (row_start);
for ($icols=1; $icols<=$maxcols; $icols++)
{
echo (col_start);
$imagefilename = $adirectory[++$i];
If (strlen($imagefilename)>0)
           {
$imagepath = $browsedir."/".$imagefilename;
$imagesize = getimagesize ($imagepath);
            if ($imagesize)
                                                                          $imagewidth = $imagesize[0];
$imageheight = $imagesize[1];
$imageratio = $imagewidth / $imageheight;
If ($imageratio > $imagemaxratio)
                                                                               $imageoutputwidth = $imagemaxwidth;
$imageoutputheight = ceil ($imagemaxwidth/$imagewidth*$imageheight);
              }
              else if ($imageratio < $imagemaxratio)
                                                                               $imageoutputheight = $imagemaxheight;
$imageoutputwidth = ceil ($imagemaxheight/$imageheight*$imagewidth);
              } else
                                                                               $imageoutputwidth = $imagemaxwidth;
$imageoutputheight = $imagemaxheight;
           }

# Display graphics

echo (a_start.$imagepath.a_close);

echo (img_start.$imagepath.img_width.$imageoutputwidth.img_height.$imageoutputheight.img_end);

echo (line_break.$adirectory[$i]);

echo (a_end);

           }
echo (col_end);
         }
}  
echo (row_end);
}
echo (table_end);
pagemenu ($browsedir, $ndirectory, $start);

}

function pagemenu ($browsedir, $ndirectory, $pg) {

echo "

page:";

$pg_num = 1;

for ($img_num = 0; $img_num <= $ndirectory;) {

if ($pg == $img_num) {
echo " *$pg_num ";
} else {
echo " $pg_num ";
}

# Establish links to other pages, each page displays four pictures, so every time the page number $pg_num increases by 1, $img_num increases by 4.

$pg_num = $pg_num + 1;
$img_num = $img_num + 4;

}

echo "n";

}

function dirtoarray ($browsedir, $extensions)
{

$nextensions = sizeof ($extensions);
$idirectory = 0;
$directory = dir($browsedir);
 
while ($entry = $directory->read())
{
for ($i=1; $i<=$nextensions; $i++)
          {
             $compare = stristr ($entry, $extensions[$i]);
If (strlen($compare) == strlen($extensions[$i]))
                                                                                         $adirectory[++$idirectory] = $entry;
             break;
           }
        }
}
$directory->close();
return $adirectory;
}

#Main program

#Variable $browsedir is the location where the graphics file is placed.

$browsedir="./images";

# The extensions of graphics files that are allowed to be browsed are placed in the array and can be added by yourself.

$extensions[1] = "jpeg";

$extensions[2] = "jpg";
$extensions[3] = "gif";
$extensions[4] = "png";
showdir (dirtoarray ($browsedir, $extensions), $start);

define ("line_break", "
");

define ("table_start", "

n");
define ("table_end", "n");
define ("row_start", " n");
define ("row_end", " n");
define ("col_start", " n ");
define ("col_end", "n n");
define ("img_start", "");
define ("img_width", " width=");
define ("img_height", " height=");
define ("a_start", '');
define ("a_end", "");
?>