Resize Landscape/Portrait Image

[coxdabd]

Hi all, I've tried looking around the web for a solution but have so far failed. I want to enable a user to upload an image (which I have done) but if it's a landscape image then I want to resize the horizontal and automatically recalculate the height and if it's a portrait image then for it to resize the height and recalculate the width. Any ideas as to how this can be done?

[Rubble]

Loads of posts in this section of the forum - try searching for resize, thumbnail etc.

[oddz]

The simplest way to achieve this is to use CSS – background-size: contain. However, it is not supported by all browsers, so you will need to determine whether it is a viable solution for your circumstances. The other sacrifice that is necessary is using a div or span with a background image rather than an image tag. Though, it is really a small sacrifice to make considering the many advantages of using a background image – resizing and centering easily.

[coxdabd]

Hi there, I was hoping to do this while the user uploads their photo rather than taking the CSS route. I've also taken a look through the forums and haven't found anything of substance as yet.

[Rubble]

There is one on this very page that does what you want started on 1 Nov: http://www.sitepoint.com/forums/show...s-the-best-way

[webdev1958]

This is a script I wrote some time ago to resize images.

Feel free to use it as is or tweak it to suit your needs.

<?php
    /*************************************************************************
    This script resizes an image so that it fits within a user specified
    max_width and max_height.
 
    The script automatically detects jpg, png and gif image format files.
 
    Input Parameters:
    -----------------    
    pic         = path to image to be resized.
    maxWidth     = maximum width.
    maxHeight     = maximum height.
    *************************************************************************/
 
    //get the passed data, validate it and assign it to variables
 
    $image = $_GET['pic'];
 
    if(!isset($_GET['maxWidth'])        || !isset($_GET['maxHeight']) ||
       !is_numeric($_GET['maxWidth'])     || empty($_GET['maxWidth'])   || 
       !is_numeric($_GET['maxHeight']) || empty($_GET['maxHeight'])  || 
       $_GET['maxWidth']  <= 0 || 
       $_GET['maxHeight'] <= 0)
    {
        $max_width = 70;        //default value
        $max_height = 70;        //default value
    }
    else
    {
        $max_width  = $_GET['maxWidth'];
        $max_height = $_GET['maxHeight'];
    }
 
    //get the original image attributes
    $size         = GetImageSize($image);
    $width         = $size[0];
    $height     = $size[1];
    $imageType     = $size[2];
 
    //scaling factors
    $xRatio = $max_width / $width;        
    $yRatio = $max_height / $height;
 
    //calculate the new width and height
    if($width <= $max_width && $height <= $max_height)    //image does not need resizing
    {
        $toWidth     = $width;
        $toHeight     = $height;
    }
    else if($xRatio * $height < $max_height)
    {
        $toHeight = round($xRatio * $height);
        $toWidth  = $max_width;        
    }
    else
    {
        $toWidth = round($yRatio * $width);
        $toHeight  = $max_height;
    }
 
    //create the resized image
    //Type of image  1=GIF  2=JPG 3=PNG 4=SWF 5=PSD 6=BMP 7=TIFF(intel byte order) 8=TIFF(motorola byte order) 9=JPC 10=JP2 11=JPX 12=JB2 13=SWC 14=IFF 15=WBMP 16=XBM
 
    $newImage = ImageCreateTrueColor($toWidth,$toHeight);    //create the new image canvas
 
    switch ($imageType)
    {       
        case 1:        //gif file
            $oldImage = ImageCreateFromGif($image);
            break;
 
        case 3:        //png file
            $oldImage = ImageCreateFromPng($image);
            break; 
 
        default:    //jpg file
            $oldImage = ImageCreateFromJpeg($image);
            break;      
    }
 
    ImageCopyResampled($newImage,$oldImage,0,0,0,0,$toWidth,$toHeight,$width,$height);    //resize the new image
 
    //output the new resized image
 
    switch ($imageType)
    {       
        case 1:        //gif file
            header('Content-type: image/gif');
            ImageGif($newImage);
            break; 
            break;
 
        case 3:        //png file
            header('Content-type: image/png');
            ImagePng($newImage);
            break; 
 
        default:    //jpg file
            header('Content-type: image/jpeg');
            ImageJpeg($newImage);
            //ImageJpeg($newImage,'newImage.jpg', -1);
            break;      
    }
 
     //clean up resources
    ImageDestroy($oldImage);
    ImageDestroy($newImage);
 
?>