resizing images

[gerkintrigg]

Hi everyone!
I'd like to find out how to change the current script I'm using. It resizes images fine, but rather than setting them to absolute figures, I'd like to work out a way whereby I can set maximum figures.

So for example, rather than saying "it MUST be 400 pixels wide by 20 Px high" I'd like to say: "it can be a maximum of 400 px wide by 20 px high, but the proportions must stay the same.

This is the script I have so far:

[code]function makeimage($filename,$newfilename,$path,$newwidth,$newheight) {

//SEARCHES IMAGE NAME STRING TO SELECT EXTENSION (EVERYTHING AFTER . )
$image_type = strstr($filename, '.');

//SWITCHES THE IMAGE CREATE FUNCTION BASED ON FILE EXTENSION
switch($image_type) {
case '.jpg':
$source = imagecreatefromjpeg($filename);
break;
case '.png':
$source = imagecreatefrompng($filename);
break;
case '.gif':
$source = imagecreatefromgif($filename);
break;
default:
echo("Error Invalid Image Type");
die;
break;
}

//CREATES THE NAME OF THE SAVED FILE
$file = $newfilename . $filename;

//CREATES THE PATH TO THE SAVED FILE
$fullpath = $path . $file;

//FINDS SIZE OF THE OLD FILE
list($width, $height) = getimagesize($filename);

//CREATES IMAGE WITH NEW SIZES
$thumb = imagecreatetruecolor($newwidth, $newheight);

//RESIZES OLD IMAGE TO NEW SIZES
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

//SAVES IMAGE AND SETS QUALITY || NUMERICAL VALUE = QUALITY ON SCALE OF 1-100
imagejpeg($thumb, $fullpath, 60);

//CREATING FILENAME TO WRITE TO DATABSE
$filepath = $fullpath;

//RETURNS FULL FILEPATH OF IMAGE ENDS FUNCTION
return $filepath;

}[/code]Thanks in advance for any help you might be able to give.

[shocker-z]

if (($height > 20) or ($width > 400)) {
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
}


Would that not do the job??

Regards
Liam

[gerkintrigg]

er... no. I tried it, but no cigar.

[HeyRay2]

Add this code:

[code=php:0]
// Set the maximum width and height
$max_width = 400;
$max_height = 20;

// Check if either dimension is over the maximum
if (($height > $max_height) || ($width > $max_width))
  {
  // Set a size factor variable, depending on which
  // dimension is greater
if ($height > $width)
    {
      $sizefactor = (double) ($max_height / $height);
    }
    else
    {
      $sizefactor = (double) ($max_width / $width) ;
    }

    $newwidth = (int) ($image_width * $sizefactor);
  $newheight = (int) ($image_height * $sizefactor);
  }
[/code]

After this line:

[code=php:0]
//FINDS SIZE OF THE OLD FILE
list($width, $height) = getimagesize($filename);
[/code]

Let us know if that works... ;)

[litebearer]

Might be of some use...

http://www.nstoia.com/toh/technical/imageresize/index.php

Lite...