Php resize width fix | 易学教程

问题

I have this function in PHP.

<?php
function zmensi_obrazok($max_dimension, $image_max_width, $image_max_height, $dir, $obrazok, $obrazok_tmp, $obrazok_size, $filename){


$postvars          = array(
"image"            => $obrazok,
"image_tmp"        => $obrazok_tmp,
"image_size"       => $obrazok_size,
"image_max_width"  => $image_max_width,
"image_max_height" => $image_max_height
);
// Array of valid extensions.
$valid_exts = array("jpg","jpeg","gif","png");
// Select the extension from the file.
$ext = end(explode(".",strtolower($obrazok)));
// Check not larger than 175kb.
if($postvars["image_size"] <= 256000){
// Check is valid extension.
if(in_array($ext,$valid_exts)){
if($ext == "jpg" || $ext == "jpeg"){
$image = imagecreatefromjpeg($postvars["image_tmp"]);
}
else if($ext == "gif"){
$image = imagecreatefromgif($postvars["image_tmp"]);
}
else if($ext == "png"){
$image = imagecreatefrompng($postvars["image_tmp"]);
}
list($width,$height) = getimagesize($postvars["image_tmp"]);

if($postvars["image_max_width"] > $postvars["image_max_height"]){
    if($postvars["image_max_width"] > $max_dimension){
            $newwidth = $max_dimension;
        } 
        else 
        {
            $newwidth = $postvars["image_max_width"];
        }

}

else
{
    if($postvars["image_max_height"] > $max_dimension)
    {
        $newheight = $max_dimension;
    }
        else
        {
            $newheight = $postvars["image_max_height"];
        }


}

$tmp = imagecreatetruecolor($newwidth,$newheight);
imagecopyresampled($tmp,$image,0,0,0,0,$newwidth,$newheight,$width,$height);

imagejpeg($tmp,$filename,100);
return "fix";
imagedestroy($image);
imagedestroy($tmp);
}

}

}

?>

Now if I want to use it, and I upload image for example 500x300px and I have set max size to 205x205px it don't want to make resized picture proportion. It make something like 375x205 (height is still OK). Can somebody help how to fix it?

回答1:

Just scale your image twice, once to match the width, once to match the height. To save on processing, get your scaling first, then do the resizing:

$max_w = 205;
$max_h = 205;

$img_w = ...;
$img_h = ...;

if ($img_w > $max_w) {
    $img_h = $img_h * $max_w / $img_w;
    $img_w = $max_w;
}

if ($img_h > $max_h) {
    $img_w = $img_w * $max_h / $img_h;
    $img_h = $max_h;
}

// $img_w and $img_h should now have your scaled down image complying with both restrictions.

来源：https://stackoverflow.com/questions/11273051/php-resize-width-fix

标签

php

image

function

resize