[RESOLVED] imagecopymerge - good and bad results?

baffled_in_UK

Hello,

Any ideas why the following code works in isolation (ie, a php file with nothing else in it) but when I drop it into my web page the image is displayed as 1,000's of letters and strange characters:

<?
  header ("Content-type: image/png"); 

  // Define the background image

$background = imagecreatefromjpeg("image1.jpg"); 

  // Define the overlay image

 $insert = imagecreatefrompng("trans.png"); 

  // Select the first pixel of the overlay image (at 0,0) and use
  // it's color to define the transparent color

  imagecolortransparent($insert,imagecolorat($insert,0,0));

  // Get overlay image width and height

  $insert_x = imagesx($insert); 
  $insert_y = imagesy($insert); 


  // Combine the images into a single output image. 

  imagecopymerge($background,$insert,0,50,0,0,$insert_x,$insert_y,25); 


  // Output the results as a png image.

  imagepng($background,"",50);  

?>

In the version that doesn't work I have all the code at the top of my page except the imagepng command, that is in a table at the point on the page I want the image displaying.

I do not have any other graphics on the page (ie. jpg's) and I was led to believe the imagepng could be anywhere in the code.

Thanks for any help.

_theworks

when calling a dynamic image from ur html just do it like

<img src="image.php" alt="my image">

so u need to keep your dynamic image in its own file so the browser thinks its an image..

baffled_in_UK

Thanks for that, it was very helpful.

I still have one small problem though, this script is for watermarking "on the fly" and I cannot seem to pass the "background" image name into the watermark.php from the page that is displaying it.

Using the usual way to pass paramters/values - watermark.php?img=name.jpg doesn't work in the img src tag.

_theworks

Well you can pass values to the image via the GET http in the image tag...

<img src="watermark.php?id=dog&color=red alt="red dog">

just use $GET['id'] or $GET['color'] in your watermark image... but make sure you dont have any blank space above or below you php tags ( <? ?> ) this can cuase your php file to error...

_theworks

Can you please post your water marking code its alot easier to trouble shoot code wen you can see it...

baffled_in_UK

Hi,

I've just tried that but the image doesn't display (at least it tries now though and is not just lots of characters).

I've never used $GET before, I assume the syntax is :

$id= $_GET['id'];

I did post the code in my original message? Here it is again (without the comments) plus the code from the file displaying the image.

<? 
header ("Content-type: image/png"); 
$id= $_GET['id'];
$image = "http://www.mydomain.com/images/$id";
$background = imagecreatefromjpeg($image); 
$insert = imagecreatefrompng("http://www.mydomain.com/images/trans.png"); 
imagecolortransparent($insert,imagecolorat($insert,0,0));
$insert_x = imagesx($insert); 
$insert_y = imagesy($insert); 
imagecopymerge($background,$insert,0,100,95,0,$insert_x,$insert_y,25); 
imagepng($background,"",50);  

?>

<img src="watermark.php?id=$id">

_theworks

try changing...

$image = "http://www.mydomain.com/images/$id";

to...

$image = "http://www.mydomain.com/images/".$id;

I did post the code in my original message? Here it is again (without the comments) plus the code from the file displaying the image

heh sorry (not very observant) :queasy:

baffled_in_UK

Still no joy.

I appreciate your help on this , if you get bored with it just let me know.

_theworks

what error is it displaying?

il try run your code now..

what about this..

u need an image name in there...
like

baffled_in_UK

No error as such, just an blank graphic (the actual size of the graphic I want displaying) with the 'X' in the top left. The one you get when an image cannot be displayed.

baffled_in_UK

Nice one.

I "echo"ed the file value into the watermark.php bit and it works.

Something weird is still happening (sometimes I have to refresh the page to get the image displayed, it displays about half the image and then puts the "image not found graphic" up again), but that is not part of this thread so I'll close this one.

Many thanks for your time and help.

_theworks

this is an example of image.php (you can test here http://theworks.net.nz/random/image.php?id=1.png or id=2.png )

<?
$image_id = $_GET['id'];

$im = imagecreatefrompng($image_id); 
imagepng($im);
?>

the images must be in the same dir as the php script (in this case) as you'll see if you look here: http://theworks.net.nz/random/

use this example to work from if you want...

Weedpacket

Try commenting out the Content-Type: header. Whatever it's trying to display is not a valid PNG file, so let's see what happens if the browser tries to render it as the default text/html.