Image resize and rename

[stylefrogcreate]

Hi there,

Got a deadline rapidly approaching and still banging my head against the wall - any help would be greatly appreciated!

Basically I'm developing a Flash application which gives the user the option to customise an ecard with a message, company name and company logo. I've got everything working apart from the logo part.

I need them to upload a logo, which is then resized and uniquely renamed, for when I pull it back in Flash.

I need to specify that neither the height or the width is greater than 75 px, and resize if it is - keeping everything in scale.

Here's the code so far:
I generate a unique variable name and use it create a new text file ($session)

$fd = fopen("$session.txt", "w");
fwrite($fd, "name=$name&message=$message&contentLoaded=true");
fclose($fd);

I then write all the text info into this - which all works perfectly.

I need to know how to let the user specify an image to upload, then once submitted I need to resize it so that neither the width nor the height is greater than 75px. We then need to save it as $session.jpg, so it has a unique name.

Please help guys - I'm pulling my hair out here!

Many, many thanks,

Matt

[sneakyimp]

step 1 is to create a form with an input of type 'file'. As far as I know, flash can't do this. some people have managed to integrate this type of form with flash pretty tightly though. you might want to search this forum and you'll find something.

if PHP is ok, create an image upload form:

<form method="post" action="upload_handler.php" enctype="multipart/form-data">
<input type="file" name="logo"><br>
<input type="submit" name="submit" value="Submit">
</form>

NOTE: that enctype part is *critical

Once you have done that, your upload_handler.php page should look into the $FILES array. It's like $POST or $_GET but is only present for forms like the one i just typed up for you. Try this for upload_handler.php

<?
print_r($_FILES);
?>

tmp_name is the name of the temporary file that was uploaded
name is the name taken from your file
type is the mime type (which could be empty depending on the browser)
error could be a number of things depending on what happened
size is - duh! size in bytes.

resizing the image can be kind of involved. try reading this:

http://us2.php.net/manual/en/features.file-upload.php#features.file-upload.post-method

[jcanker]

We have a site that also needs to resize images...we use imagemagik and it's php plugin and just resize it by imagemagik commands. It's a pretty powerful batch image processing program--especially for open source 🙂
http://www.imagemagick.org/script/index.php

[stylefrogcreate]

Right - I've got the following code to handle the resize:

<?php
function thumbnail($image_path,$thumb_path,$image_name) {
$max_width = 75;
$max_height = 75;

$size = getimagesize($image_path.$image_name);
$width = $size[0];
$height = $size[1];

if($width != FALSE && $height != FALSE) {
    $x_ratio = $max_width / $width;
    $y_ratio = $max_height / $height;

    if(($width <= $max_width) && ($height <= $max_height)) {
        $disp_width = $width;
        $disp_height = $height;
    } elseif(($x_ratio * $height) < $max_height) {
        $disp_height = ceil($x_ratio * $height);
        $disp_width = $max_width;
    } else {
        $disp_width = ceil($y_ratio * $width);
        $disp_height = $max_height;
    }
} else {
    return false;
}

$src_img = imagecreatefromjpeg($image_path.$image_name);
$dst_img = imagecreatetruecolor($disp_width,$disp_height);

imagecopyresized($dst_img,$src_img,0,0,0,0,$disp_width,$disp_height,imagesx($src_img),imagesy($src_img));
imagejpeg($dst_img, $thumb_path.$image_name);
return true;

}
?>

With regards to renaming the image file - how would I go about saving it with a unique name? I need to name it with the vaue contained with $session, as thats how I'll call it back into Flash.

Thanks again!

[jcanker]

Some of the more experienced folks around here might have a more sophisticated method, but I'd use fopen (http://us3.php.net/manual/en/function.fopen.php) and fwrite, just using the $SESSION info as the name. As far as guaranteeing that it's unique, you'd really be best to store the names in a db and run a check before writing the file with that name....better yet, run the check before you allow that name to be used as the $SESSION value.

[sneakyimp]

you can use copy() to just copy a file.

imagejpeg() is a good way to write a new resized file.

to create a unique filename, you could try uniqid() or something like this:

$i = 0;
while (file_exists($i . '.jpg')) {
$i++;
}