[SOLVED] Watermarking an image

[gerkintrigg]

Hi everyone. i'm trying to work out how to watermark an image...

I have done it before at build.nextdaygraphics.com but I'm trying to do it for the new design at www.nextdaygraphics.com and it's not working as I'd like...

 

the code I have is:

 

<?php
    ob_start();

    $edgePadding=15;                        // used when placing the watermark near an edge
    $quality=100;                           // used when generating the final image
    $default_watermark='ndg.png';  // the default image to use if no watermark was chosen

$watermark = "ndg.png"; // location of watermark
$original = $img; //location of original
$_POST['watermark']='ndg.png';
$_POST['process']='y';
    
    if(isset($_POST['process'])){
        // an image has been posted, let's get to the nitty-gritty
        if(isset($original)){
        
            // be sure that the other options we need have some kind of value
            if(!isset($_POST['save_as'])) $_POST['save_as']='jpeg';
            if(!isset($_POST['v_position'])) $_POST['v_position']='center';
            if(!isset($_POST['h_position'])) $_POST['h_position']='center';
            if(!isset($_POST['wm_size'])) $_POST['wm_size']='1';
            if(!isset($_POST['watermark'])) $_POST['']=$default_watermark;
		if(!isset($_POST['watermarkee'])) $_POST['']=$original;
        
            // file upload success
            $size=getimagesize($original);
            if($size[2]==2 || $size[2]==3){
                // it was a JPEG or PNG image, so we're OK so far
                
                //$original=$_FILES['watermarkee']['tmp_name'];
                $target_name=date('YmdHis').'_'.
                    // if you change this regex, be sure to change it in generated-images.php:26
                    preg_replace('`[^a-z0-9-_.]`i','',$original);
                $target=dirname(__FILE__).'/results/'.$target_name;
                $watermark=dirname(__FILE__).'/watermarks/'.$_POST['watermark'];
                $wmTarget=$watermark.'.tmp';

                $origInfo = getimagesize($original); 
                $origWidth = $origInfo[0]; 
                $origHeight = $origInfo[1]; 

                $waterMarkInfo = getimagesize($watermark);
                $waterMarkWidth = $waterMarkInfo[0];
                $waterMarkHeight = $waterMarkInfo[1];
        
                // watermark sizing info
                if($_POST['wm_size']=='larger'){
                    $placementX=0;
                    $placementY=0;
                    $_POST['h_position']='center';
                    $_POST['v_position']='center';
                	$waterMarkDestWidth=$waterMarkWidth;
                	$waterMarkDestHeight=$waterMarkHeight;
                    
                    // both of the watermark dimensions need to be 5% more than the original image...
                    // adjust width first.
                    if($waterMarkWidth > $origWidth*1.05 && $waterMarkHeight > $origHeight*1.05){
                    	// both are already larger than the original by at least 5%...
                    	// we need to make the watermark *smaller* for this one.
                    	
                    	// where is the largest difference?
                    	$wdiff=$waterMarkDestWidth - $origWidth;
                    	$hdiff=$waterMarkDestHeight - $origHeight;
                    	if($wdiff > $hdiff){
                    		// the width has the largest difference - get percentage
                    		$sizer=($wdiff/$waterMarkDestWidth)-0.05;
                    	}else{
                    		$sizer=($hdiff/$waterMarkDestHeight)-0.05;
                    	}
                    	$waterMarkDestWidth-=$waterMarkDestWidth * $sizer;
                    	$waterMarkDestHeight-=$waterMarkDestHeight * $sizer;
                    }else{
                    	// the watermark will need to be enlarged for this one
                    	
                    	// where is the largest difference?
                    	$wdiff=$origWidth - $waterMarkDestWidth;
                    	$hdiff=$origHeight - $waterMarkDestHeight;
                    	if($wdiff > $hdiff){
                    		// the width has the largest difference - get percentage
                    		$sizer=($wdiff/$waterMarkDestWidth)+0.05;
                    	}else{
                    		$sizer=($hdiff/$waterMarkDestHeight)+0.05;
                    	}
                    	$waterMarkDestWidth+=$waterMarkDestWidth * $sizer;
                    	$waterMarkDestHeight+=$waterMarkDestHeight * $sizer;
                    }
                }else{
                $waterMarkDestWidth=round($origWidth * floatval($_POST['wm_size']));
                $waterMarkDestHeight=round($origHeight * floatval($_POST['wm_size']));
                if($_POST['wm_size']==1){
                    $waterMarkDestWidth-=2*$edgePadding;
                    $waterMarkDestHeight-=2*$edgePadding;
                }
                }

                // OK, we have what size we want the watermark to be, time to scale the watermark image
                resize_png_image($watermark,$waterMarkDestWidth,$waterMarkDestHeight,$wmTarget);
                
                // get the size info for this watermark.
                $wmInfo=getimagesize($wmTarget);
                $waterMarkDestWidth=$wmInfo[0];
                $waterMarkDestHeight=$wmInfo[1];

                $differenceX = $origWidth - $waterMarkDestWidth;
                $differenceY = $origHeight - $waterMarkDestHeight;

                // where to place the watermark?
                switch($_POST['h_position']){
                    // find the X coord for placement
                    case 'left':
                        $placementX = $edgePadding;
                        break;
                    case 'center':
                        $placementX =  round($differenceX / 2);
                        break;
                    case 'right':
                        $placementX = $origWidth - $waterMarkDestWidth - $edgePadding;
                        break;
                }

                switch($_POST['v_position']){
                    // find the Y coord for placement
                    case 'top':
                        $placementY = $edgePadding;
                        break;
                    case 'center':
                        $placementY =  round($differenceY / 2);
                        break;
                    case 'bottom':
                        $placementY = $origHeight - $waterMarkDestHeight - $edgePadding;
                        break;
                }
       
                if($size[2]==3)
                    $resultImage = imagecreatefrompng($original);
                else
                    $resultImage = imagecreatefromjpeg($original);
                imagealphablending($resultImage, TRUE);
        
                $finalWaterMarkImage = imagecreatefrompng($wmTarget);
                $finalWaterMarkWidth = imagesx($finalWaterMarkImage);
                $finalWaterMarkHeight = imagesy($finalWaterMarkImage);
        
                imagecopy($resultImage,
                          $finalWaterMarkImage,
                          $placementX,
                          $placementY,
                          0,
                          0,
                          $finalWaterMarkWidth,
                          $finalWaterMarkHeight
                );
                
                if($size[2]==3){
                    imagealphablending($resultImage,FALSE);
                    imagesavealpha($resultImage,TRUE);
                    imagepng($resultImage,$target,$quality);
                }else{
                    imagejpeg($resultImage,$target,$quality); 
                }

                imagedestroy($resultImage);
                imagedestroy($finalWaterMarkImage);

                // display resulting image for download
$watermarked='watermark/results/'.$target_name;
                unlink($wmTarget);
            }else{
?>
   <div>
    <span class="Brown_Header_Text">Watermarked Image</span>
    <p class="boldText">The image uploaded was not a JPEG or PNG image.</p>
   </div>
<?php
            }
        }else{
?>
   <div>
    <span class="Brown_Header_Text">Watermarked Image</span>
    <p class="boldText">Unable to upload the image to watermark.</p>
   </div>
<?php
        }
    }
    $page_display=ob_get_clean();



echo $page_display;?>

 

The error I'm getting is the output code:

   <div>
    <span class="Brown_Header_Text">Watermarked Image</span>
    <p class="boldText">Unable to upload the image to watermark.</p>
   </div>

But i have no idea why it's hitting this else statement... (I didn't write this code and am rather at a loss with the GD library)

 

I'm doing it slightly differently to the first site for a number of reasons and think that this code should work... but it's not. any suggestions please?

[MadTechie]

looks like "process" isn't being set in the form...

 

try

print_r($_POST); at the top of the code and post the results here

[gerkintrigg]

Good call it was entirely to do with posted variables and a call to an undefined function. Once i included the function and changed the posted variables, it worked.

 

Thanks a lot!