mysql/php image resize proportionally problem

[willy]

hey guys - i need help with this code... currenty it just takes an
image and resize it to 450 by 337. What i need it to do is to make the
width 450, and just have the height be resized proptionally to widths
new lenght. Thanks!

if(!$bad_file_flag)
{
// filename will just be the current UNIX timestamp...
$fname = time() . $i;

$new_width = 450;
$new_height = 337;
// move_uploaded_file($_FILES[$element_name][tmp_name],
$vehicle_image_dir . "/$fname$file_extension");
// chmod($vehicle_image_dir . "/$fname$file_extension", 0666);
$tmp_image=imagecreatefromjpeg($_FILES[$element_name]['tmp_name']);
$width = imagesx($tmp_image);
$height = imagesy($tmp_image);
$new_image = imagecreatetruecolor($new_width,$new_height);
ImageCopyResized($new_image, $tmp_image,0,0,0,0, $new_width,
$new_height, $width, $height);
ImageJPEG($new_image,$vehicle_image_dir .
"/$fname$file_extension");
ImageDestroy($tmp_image);
ImageDestroy($new_image);

// move_uploaded_file($image_buffer, $vehicle_image_dir .
"/resized$fname$file_extension");
chmod($vehicle_image_dir . "/$fname$file_extension", 0666);

mysql_query("INSERT INTO dah_images (filename, vehicle_id)
VALUES('$fname$file_extension', $insert_id)");
}
else
{
// remove the bad file - we don't know what this is!
@unlink($_FILES[$element_name][tmp_name]);
}

[frizzle]

Get the current height & width of the image you are going to
manipulate.

Imagine it's 750 px wide, and 540 pixels high.

The new picture HAS to be 450 wide. 100% / 750 (original width) * 450
(new width) = 60 %, which means the new image will be 60% smaller.

New height = 540 (old height) / 100 % (gets 1 %) * 60 % (new
percentage) = 324

750 x 540 = 450 x 324.

All just a matter of maths... :D

[wrw[three]]

Yeah i know how to do it mathematically but just have a hard time
making it into code...

[frizzle]

hmm, sorry then, i must be missing something here...

[wrw[three]]

i just don't know how to insert the code that you wrote into the code
that i have.... thanxs

[frizzle]

First get the image size of the original image.
http://php.net/getimagesize.

Transform that with my maths and then replace the following in your
code:

$new_width = 450;
$new_height = 337;

With:

$new_width = 450;
$new_height =
$the_new_height_i_showed_you;

If still not clear, ask! :D
Good luck with it.

[wrw[three]]

so here is my problem

$new_width = 450;
$new_height = How do i transform the math
into code? i don't know the proper way to do it....

thanxs for the help

[frizzle]

I haven't got any time today to help you out, but i'll have a look on
it on monday...

[frizzle]

If i'm not mistaking, the following code should be ready to go:

if(!$bad_file_flag)
{

// define new width, and height will be calculated by itself
$new_width = 450;

// filename will just be the current UNIX timestamp...
$fname = time() . $i;

//
move_uploaded_file($_FILES[$element_name][tmp_name],$vehicle_image_dir
.. "/$fname$file_extension");
// chmod($vehicle_image_dir . "/$fname$file_extension", 0666);
$tmp_image =imagecreatefromjpeg($_FILES[$element_name]['tmp_name']);
$width = imagesx($tmp_image);
$height = imagesy($tmp_image);

$new_height = round(($height / 100) * (100 / $width * $new_width),
0);

$new_image = imagecreatetruecolor($new_width, $new_height);
ImageCopyResized($new_image, $tmp_image,0,0,0,0, $new_width,
$new_height, $width, $height);
ImageJPEG($new_image,$vehicle_image_dir ."/$fname$file_extension");
ImageDestroy($tmp_image);
ImageDestroy($new_image);

// move_uploaded_file($image_buffer, $vehicle_image_dir
.."/resized$fname$file_extension");
chmod($vehicle_image_dir . "/$fname$file_extension", 0666);

mysql_query("INSERT INTO dah_images (filename,
vehicle_id)VALUES('$fname$file_extension', $insert_id)");
}
else
{
// remove the bad file - we don't know what this is!
@unlink($_FILES[$element_name][tmp_name]);
};