imagecopymerge

(PHP 4 >= 4.0.1, PHP 5, PHP 7)

imagecopymerge — 拷贝并合并图像的一部分

说明

bool imagecopymerge ( resource $dst_im , resource $src_im , int $dst_x , int $dst_y , int $src_x , int $src_y , int $src_w , int $src_h , int $pct )

将 src_im 图像中坐标从 src_x，src_y 开始，宽度为 src_w，高度为 src_h 的一部分拷贝到 dst_im 图像中坐标为 dst_x 和 dst_y 的位置上。两图像将根据 pct 来决定合并程度，其值范围从 0 到 100。当 pct = 0 时，实际上什么也没做，当为 100 时对于调色板图像本函数和 imagecopy() 完全一样，它对真彩色图像实现了 alpha 透明。

Note:
本函数是 PHP 4.0.6 新加的。

User Contributed Notes

Leo 04-Jan-2012 06:14


The following function creates mask of a true color image for a given color. Beforehand for creating an image mask I used to loop over all image pixels and check their color using imagecolorat and copy if the color matches with imagesetpixel. This was very slow for large images, so the following code improves the process.



<?php



    function getOppositeColor ($color)

    {

        return (

                    ( (255 - ($color >> 16) & 0xFF) << 16 ) +

                    ( (255 - ($color >> 8  ) & 0xFF) << 8  ) +

                    ( (255 - ($color         ) & 0xFF)         )

                );

    }



    function createImageMask (&$image, $color)

    {

        $w = imagesx ($image);

        $h = imagesy ($image);

        

        $tmpImage = imagecreatetruecolor ($w, $h);



        imagecopy ($tmpImage, $image, 0, 0, 0, 0, $w, $h);



        imagefilter ($image, IMG_FILTER_NEGATE);



        imagecolortransparent ($image, getOppositeColor ($color));

        

        imagecopymerge ($tmpImage, $image, 0, 0, 0, 0, $w, $h, 50);



        imagedestroy ($image);

        

        $image = $tmpImage;        

    }



?>



So for example, if we have a photo and we specify color = (255, 0, 0), i.e. red, the result will be image of the same size with red pixels everywhere the original photo was red and grey pixels exerywhere else.

Leo 04-Jan-2012 03:27


imagecopymerge PHP function helped me to create a fast method that replaces one color by another in true color images.



Beforehand for this purpose I had to loop over all the pixels of an image and replace color pixel by pixel using imagecolorat and imagesetpixel; this method is really slow for large images.



So here is the fast one:



<?php



function replaceColorInImage ($image, $old_r, $old_g, $old_b, $new_r, $new_g, $new_b)

{

    imagecolortransparent ($image, imagecolorallocate ($image, $old_r, $old_g, $old_b));

    

    $w = imagesx ($image);

    $h = imagesy ($image);

    

    $resImage = imagecreatetruecolor ($w, $h);

    

    imagefill ($resImage, 0, 0, imagecolorallocate ($resImage, $new_r, $new_g, $new_b));

    

    imagecopymerge ($resImage, $image, 0, 0, 0, 0, $w, $h, 100);

    

    return $resImage;

}



?>

thciobanu 09-Mar-2011 09:56


This is what I use for merging two images while respecting the alpha channel (formulas are taken from the wikipedia article on alpha compositing; they're not too pretty as I didn't really try to make them look so, but instead just work and make sense when checked out months from now), with a quirk - an additional parameter (that defaults to NULL to be ignored) to manually specify a "transparent" color, which won't be copied over from the source to the destination. In comparison to the other implementation here, only one pass over $src_im is done, but more calculations are performed:



<?php

function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct, $trans = NULL)

{

  $dst_w = imagesx($dst_im);

  $dst_h = imagesy($dst_im);



  // bounds checking

  $src_x = max($src_x, 0);

  $src_y = max($src_y, 0);

  $dst_x = max($dst_x, 0);

  $dst_y = max($dst_y, 0);

  if ($dst_x + $src_w > $dst_w)

    $src_w = $dst_w - $dst_x;

  if ($dst_y + $src_h > $dst_h)

    $src_h = $dst_h - $dst_y;



  for($x_offset = 0; $x_offset < $src_w; $x_offset++)

    for($y_offset = 0; $y_offset < $src_h; $y_offset++)

    {

      // get source & dest color

      $srccolor = imagecolorsforindex($src_im, imagecolorat($src_im, $src_x + $x_offset, $src_y + $y_offset));

      $dstcolor = imagecolorsforindex($dst_im, imagecolorat($dst_im, $dst_x + $x_offset, $dst_y + $y_offset));



      // apply transparency

      if (is_null($trans) || ($srccolor !== $trans))

      {

        $src_a = $srccolor['alpha'] * $pct / 100;

        // blend

        $src_a = 127 - $src_a;

        $dst_a = 127 - $dstcolor['alpha'];

        $dst_r = ($srccolor['red'] * $src_a + $dstcolor['red'] * $dst_a * (127 - $src_a) / 127) / 127;

        $dst_g = ($srccolor['green'] * $src_a + $dstcolor['green'] * $dst_a * (127 - $src_a) / 127) / 127;

        $dst_b = ($srccolor['blue'] * $src_a + $dstcolor['blue'] * $dst_a * (127 - $src_a) / 127) / 127;

        $dst_a = 127 - ($src_a + $dst_a * (127 - $src_a) / 127);

        $color = imagecolorallocatealpha($dst_im, $dst_r, $dst_g, $dst_b, $dst_a);

        // paint

        if (!imagesetpixel($dst_im, $dst_x + $x_offset, $dst_y + $y_offset, $color))

          return false;

        imagecolordeallocate($dst_im, $color);

      }

    }

  return true;

}



// use it like this (identical to imagecopymerge)

function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct)

// or this

function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct, array('red' => 1, 'green' => 2, 'blue' => 3, 'alpha' =>4))

?>

killing_wombles0000 at hotmail dot com 17-Feb-2011 06:27


Anyone wanting to create a reflecion of an image. Simple process that copies, line by line, from the bottom of the image, a given number of pixels. Each line gets gradually more transparent. Outputs PNG to screen.



This is pretty hot-coded - all four input variables (input image, reflection height, starting transparency, gap between image and reflection) are set manually here.



<?php

    $in = imagecreatefromjpeg('C:\test.jpg');

    $reflection_strength = 120;        //    starting transparency (0-127, 0 being opaque)

    $reflection_height = 40;        //     height of reflection in pixels

    $gap = 10;                        //    gap between image and reflection

    

    $orig_height = imagesy($in);                                //    store height of original image

    $orig_width = imagesx($in);                                    //    store height of original image

    $output_height = $orig_height + $reflection_height + $gap;    //    calculate height of output image

    

    // create new image to use for output. fill with transparency. ALPHA BLENDING MUST BE FALSE

    $out = imagecreatetruecolor($orig_width, $output_height);

    imagealphablending($out, false);

    $bg = imagecolortransparent($out, imagecolorallocatealpha($out, 255, 255, 255, 127));

    imagefill($out, 0, 0, $bg);

    imagefilledrectangle($out, 0, 0, imagesx($in), imagesy($in), $bg1);

    

    // copy original image onto new one, leaving space underneath for reflection and 'gap'

    imagecopyresampled ( $out , $in , 0, 0, 0, 0, imagesx($in), imagesy($in), imagesx($in), imagesy($in));



     // create new single-line image to act as buffer while applying transparency

    $reflection_section = imagecreatetruecolor(imagesx($in), 1);

    imagealphablending($reflection_section, false);

    $bg1 = imagecolortransparent($reflection_section, imagecolorallocatealpha($reflection_section, 255, 255, 255, 127));

    imagefill($reflection_section, 0, 0, $bg1);



    // 1. copy each line individually, starting at the 'bottom' of the image, working upwards. 

    // 2. set transparency to vary between reflection_strength and 127

    // 3. copy line back to mirrored position in original

    for ($y = 0; $y<$reflection_height;$y++)

    {    

        $t = ((127-$reflection_strength) + ($reflection_strength*($y/$reflection_height)));

        imagecopy($reflection_section, $out, 0, 0, 0, imagesy($in)  - $y, imagesx($in), 1);

        imagefilter($reflection_section, IMG_FILTER_COLORIZE, 0, 0, 0, $t);

        imagecopyresized($out, $reflection_section, $a, imagesy($in) + $y + $gap, 0, 0, imagesx($in) - (2*$a), 1, imagesx($in), 1);

    }

    

    // output image to view

    header('Content-type: image/png');

    imagesavealpha($out,true);

    imagepng($out);

?>

Fred 24-Sep-2010 08:39


TO merge two images with alpha - use a brush to draw a zero length line in the centre of the target image, using the src img as the brush img. The code probably explains it better:





<?php


$src = imagecreatefromstring(file_get_contents("location of src"));


$dest = imagecreatefromstring(file_get_contents("location of dest"));





// Set the brush


imagesetbrush($dest, $src);


// Draw a couple of brushes, each overlaying each


imageline($dest, imagesx($dest) / 2, imagesy($dest) / 2, imagesx($dest) / 2, imagesy($dest) / 2, IMG_COLOR_BRUSHED);





header('Content-Type: image/png');


imagepng($dest);


?>





This is simple and has reasonable performance.

Sina Salek 09-Aug-2009 10:26


I've just checked PHP's issue tracker and a core developer says that this function was never meant to support alpha channel! and they refused to commit the provided patch! so ridicules 


Anyway i tried rodrigo's workaround and it worked quite well, thanks rodrigo for sharing it.


I came up with another idea which is much faster than his solution, (it may need a little bit more memory)





Hope it helps someone.





<?php


/**


 * PNG ALPHA CHANNEL SUPPORT for imagecopymerge();


 * by Sina Salek


 *


 * Bugfix by Ralph Voigt (bug which causes it


 * to work only for $src_x = $src_y = 0. 


 * Also, inverting opacity is not necessary.)


 * 08-JAN-2011


 *


 **/


    function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct){


        // creating a cut resource


        $cut = imagecreatetruecolor($src_w, $src_h);





        // copying relevant section from background to the cut resource


        imagecopy($cut, $dst_im, 0, 0, $dst_x, $dst_y, $src_w, $src_h);


        


        // copying relevant section from watermark to the cut resource


        imagecopy($cut, $src_im, 0, 0, $src_x, $src_y, $src_w, $src_h);


        


        // insert cut resource to destination image


        imagecopymerge($dst_im, $cut, $dst_x, $dst_y, 0, 0, $src_w, $src_h, $pct);


    } 





?>

santin1991[at]gmail[dot]com 24-Apr-2009 01:16


Add logo on image script.


<?php


/**


 * Put logo on low right jpeg image


 * used stefan's script for position


 **/


$logo_file = "logo.png"; 


$image_file = "img.jpg"; 


$targetfile = "img2.jpg";


$photo = imagecreatefromjpeg($image_file);


$fotoW = imagesx($photo);


$fotoH = imagesy($photo);


$logoImage = imagecreatefrompng($logo_file);


$logoW = imagesx($logoImage); 


$logoH = imagesy($logoImage); 


$photoFrame = imagecreatetruecolor($fotoW,$fotoH);


$dest_x = $fotoW - $logoW;


$dest_y = $fotoH - $logoH;


imagecopyresampled($photoFrame, $photo, 0, 0, 0, 0, $fotoW, $fotoH, $fotoW, $fotoH);


imagecopy($photoFrame, $logoImage, $dest_x, $dest_y, 0, 0, $logoW, $logoH);


imagejpeg($photoFrame, $targetfile);  


echo '<img src="'.$targetfile.'" />';


?>

rodrigo dot polo at gmail dot com 25-Jan-2009 11:52


<?php


/**


 * PNG ALPHA CHANNEL SUPPORT for imagecopymerge();


 * This is a function like imagecopymerge but it handle alpha channel well!!!


 **/





// A fix to get a function like imagecopymerge WITH ALPHA SUPPORT


// Main script by aiden dot mail at freemail dot hu 


// Transformed to imagecopymerge_alpha() by rodrigo dot polo at gmail dot com


function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct){


    if(!isset($pct)){ 


        return false; 


    }


    $pct /= 100;


    // Get image width and height


    $w = imagesx( $src_im );


    $h = imagesy( $src_im );


    // Turn alpha blending off


    imagealphablending( $src_im, false );


    // Find the most opaque pixel in the image (the one with the smallest alpha value)


    $minalpha = 127;


    for( $x = 0; $x < $w; $x++ )


    for( $y = 0; $y < $h; $y++ ){


        $alpha = ( imagecolorat( $src_im, $x, $y ) >> 24 ) & 0xFF;


        if( $alpha < $minalpha ){ 


            $minalpha = $alpha; 


        }


    }


    //loop through image pixels and modify alpha for each


    for( $x = 0; $x < $w; $x++ ){


        for( $y = 0; $y < $h; $y++ ){


            //get current alpha value (represents the TANSPARENCY!)


            $colorxy = imagecolorat( $src_im, $x, $y );


            $alpha = ( $colorxy >> 24 ) & 0xFF;


            //calculate new alpha


            if( $minalpha !== 127 ){ 


                $alpha = 127 + 127 * $pct * ( $alpha - 127 ) / ( 127 - $minalpha ); 


            } else { 


                $alpha += 127 * $pct;


            }


            //get the color index with new alpha


            $alphacolorxy = imagecolorallocatealpha( $src_im, ( $colorxy >> 16 ) & 0xFF, ( $colorxy >> 8 ) & 0xFF, $colorxy & 0xFF, $alpha );


            //set pixel with the new color + opacity


            if( !imagesetpixel( $src_im, $x, $y, $alphacolorxy ) ){ 


                return false; 


            }


        }


    }


    // The image copy


    imagecopy($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h);


}





// USAGE EXAMPLE:


$img_a = imagecreatefrompng('image1.png');


$img_b = imagecreatefrompng('wm2.png');





// SAME COMMANDS:


imagecopymerge_alpha($img_a, $img_b, 10, 10, 0, 0, imagesx($img_b), imagesy($img_b),50);





// OUTPUT IMAGE:


header("Content-Type: image/png");


imagesavealpha($img_a, true);


imagepng($img_a, NULL);


?>

gigitrix 03-Sep-2008 03:01


Some highly amusing stuff: This code appears normal and is a way to cut out slices of an image randomly.



<?php

header("Content-Type: image/jpeg");

$width=837;

$height=771;

$origim = imagecreatefromjpeg("theimage.jpeg"); /* Attempt to open */

$imagetodisplay=imagecreate($width, $height);



for($i=0;$i<=100;$i++)

{

$xPos=rand(0,$width-9);

$yPos=rand(0,$height-9);

imagecopy($imagetodisplay, $origim, $xPos, $yPos , $xPos, $yPos , 10  , 10);

}



imagejpeg($imagetodisplay);

imagedestroy($imagetodisplay);

imagedestroy($origim);

?>



Try running this however and an omitted detail adds to the fun. Since the first colour that is defined is taken to be the background colour, we have a random colour selected from $origim as the background colour for $imagetodisplay, but this random colour is weighted according to the background image. It was a surprise (I thought the bg would be black) but I am now keeping it as it looks good.

eric 10-Jul-2007 10:57


you need to stream the image out after processing ...something like



<?php



// All of your existing code



imagepng($image);



?>

Al 09-Jul-2007 04:23


Check your header... He is false... 



<?php

header("Content-Type: image/png");

?>

jay at zylex dot net dot nz 25-Feb-2007 12:45


Hi

i wrote this script to add a watermark image into the bottom right a larger image. Its very basic i know but its all i need for now. It also is an easy function for noobs to grasp. It just takes an two image types as arguments



for example 

$image = imagecreatefromjpeg("FILELOCATION");

$insert = imagecreatefrompng("WATERMARKFILELOCATION");

$image = image_overlap($image, $insert);



function image_overlap($background, $foreground){

   $insertWidth = imagesx($foreground);

   $insertHeight = imagesy($foreground);



   $imageWidth = imagesx($background);

   $imageHeight = imagesy($background);



   $overlapX = $imageWidth-$insertWidth-5;

   $overlapY = $imageHeight-$insertHeight-5;

               imagecolortransparent($foreground,

imagecolorat($foreground,0,0));                imagecopymerge($background,$foreground,

$overlapX,$overlapY,0,0,$insertWidth,$insertHeight,100);   return $background;

    }



It doesnt smooth the edges between the two images but it works easily.

jylyn at hotmail dot com 22-Feb-2006 10:49


A few corrections to the code supplied by nick at prient:



$iTemplate should be $iBackground

$iWorking should be $iSource



After fixing those two I found the script really useful, thanks!

nick at prient dot co dot uk 01-Nov-2005 11:15


Task: Rotate a large image, then reduce it in size and place it on a small background (i.e. as an Inset).



Problem: If you resize the image first, the rotation becomes hugely aliased...  So, it makes sense to rotate it first, then shrink it.

Unfortunately, when you resample the image, you lose the background color (at least, some of it may change), so you can no longer set transparancy as you require.  If instead you resize the image (rather than resample), again, the aliasing looks bad.



Solution:  Resize the background - make it bigger.  Then add the original (large) inset, and resize the whole thing back to normal.



<?php

/* We will shrink the inset to 25% */

$resizePercentage = 0.25;



/* Load a source image and a background */

$iSource = ImageCreateFromJpeg($source_file);

$iBackground = ImageCreateFromJpeg($background_file);



/* Do something here, such a rotate, skew etc */

...

/* Assume $iSource is still the image we want to insert onto the background */



/* Set the background color to be transparent */

$cBackground = ImageColorClosest($iSource, 255, 0, 255);

ImageColorTransparent($iSource, $cBackground);



/* Resize the background - make it huge */

$iBackground = ImageResize($iTemplate, ImageSX($iBackground ) / $resizePercentage, ImageSY($iBackground ) / $resizePercentage);

/* Place the image on the background - all full size, so no aliasing issues */

ImageCopyMerge($iBackground , $iSource, 

    ((ImageSX($iBackground ) - ImageSX($iSource)) / 2), 

    ((ImageSY($iBackground ) - ImageSY($iSource)) / 2) - 25, 0, 0, ImageSX($iWorking), ImageSY($iSource), 100);

/* Shrink the combined image... no issues with transparancy! */

$iBackground = ImageResize($iTemplate, ImageSX($iBackground ) * $resizePercentage, ImageSY($iBackground ) * $resizePercentage);



/* Output the image as a PNG */

header("Content-Type: image/png");

ImagePng($iBackground);

exit();



function ImageResize($pImage, $t_width, $t_height) {

  // Target image

  $iCanvas = @ImageCreateTrueColor($t_width, $t_height);

  // Source dimensions

  $s_width = ImageSX($pImage);

  $s_height = ImageSY($pImage);

  // Copy image

  ImageCopyResampled($iCanvas, $pImage, 0, 0, 0, 0, $t_width, $t_height, $s_width, $s_height);

  // Return image

  return $iCanvas;

}

?>

Ascent [at] WebAQ.com 24-May-2005 11:41


First you need make 0~9 gif format images and background image.



<?php

/*

make random image number check

20050524 by ascent WebAQ.com

*/



$rands = rand(1000,9999);



session_start();

$_SESSION['random_image_number_check'] = $rands;



$bg = './random_image_bg.jpg';

$numimgp = './random_image_number_%d.gif';



$numimg1 = sprintf($numimgp,substr($rands,0,1));

$numimg2 = sprintf($numimgp,substr($rands,1,1));

$numimg3 = sprintf($numimgp,substr($rands,2,1));

$numimg4 = sprintf($numimgp,substr($rands,3,1));

$ys1 = rand(-4,4);

$ys2 = rand(-4,4);

$ys3 = rand(-4,4);

$ys4 = rand(-4,4);



$bgImg = imageCreateFromJPEG($bg);

$nmImg1 = imageCreateFromGIF($numimg1);

$nmImg2 = imageCreateFromGIF($numimg2);

$nmImg3 = imageCreateFromGIF($numimg3);

$nmImg4 = imageCreateFromGIF($numimg4);

imageCopyMerge($bgImg, $nmImg1, 10, $ys1, 0, 0, 20, 30, 50);

imageCopyMerge($bgImg, $nmImg2, 30, $ys2, 0, 0, 20, 30, 50);

imageCopyMerge($bgImg, $nmImg3, 50, $ys3, 0, 0, 20, 30, 50);

imageCopyMerge($bgImg, $nmImg4, 70, $ys4, 0, 0, 20, 30, 50);

header("Content-type: image/jpg");

ImageJPEG($bgImg,"",100);

imagedestroy($bgImg);

imagedestroy($nmImg1);

imagedestroy($nmImg2);

imagedestroy($nmImg3);

imagedestroy($nmImg4);

?>



enjoy!

Steve 23-May-2005 08:03


Building upon backglancer's and stefan's posts below, the following script will lay a 24-bit PNG watermark over any image.



To prepare a 24-bit watermark, I recommend creating a white logo or text over a transparent background in Photoshop.  Save this as a 24-bit PNG via 'Save for the Web...'.  Be sure to set the transparency of the logo layer in Photoshop itself.  30-40% is a good setting.



Once the assets are prepared, throw the full or relative server paths at the watermark function below:



/******************************************************************/



function watermark($sourcefile, $watermarkfile) {

  

    #

    # $sourcefile = Filename of the picture to be watermarked.

    # $watermarkfile = Filename of the 24-bit PNG watermark file.

    #

    

    //Get the resource ids of the pictures

    $watermarkfile_id = imagecreatefrompng($watermarkfile);

    

    imageAlphaBlending($watermarkfile_id, false);

    imageSaveAlpha($watermarkfile_id, true);



    $fileType = strtolower(substr($sourcefile, strlen($sourcefile)-3));



    switch($fileType) {

        case('gif'):

            $sourcefile_id = imagecreatefromgif($sourcefile);

            break;

            

        case('png'):

            $sourcefile_id = imagecreatefrompng($sourcefile);

            break;

            

        default:

            $sourcefile_id = imagecreatefromjpeg($sourcefile);

    }



    //Get the sizes of both pix   

  $sourcefile_width=imageSX($sourcefile_id);

  $sourcefile_height=imageSY($sourcefile_id);

  $watermarkfile_width=imageSX($watermarkfile_id);

  $watermarkfile_height=imageSY($watermarkfile_id);



    $dest_x = ( $sourcefile_width / 2 ) - ( $watermarkfile_width / 2 );

    $dest_y = ( $sourcefile_height / 2 ) - ( $watermarkfile_height / 2 );

    

    // if a gif, we have to upsample it to a truecolor image

    if($fileType == 'gif') {

        // create an empty truecolor container

        $tempimage = imagecreatetruecolor($sourcefile_width,

                                                                            $sourcefile_height);

        

        // copy the 8-bit gif into the truecolor image

        imagecopy($tempimage, $sourcefile_id, 0, 0, 0, 0, 

                            $sourcefile_width, $sourcefile_height);

        

        // copy the source_id int

        $sourcefile_id = $tempimage;

    }



    imagecopy($sourcefile_id, $watermarkfile_id, $dest_x, $dest_y, 0, 0,

                        $watermarkfile_width, $watermarkfile_height);



    //Create a jpeg out of the modified picture

    switch($fileType) {

    

        // remember we don't need gif any more, so we use only png or jpeg.

        // See the upsaple code immediately above to see how we handle gifs

        case('png'):

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

            imagepng ($sourcefile_id);

            break;

            

        default:

            header("Content-type: image/jpg");

            imagejpeg ($sourcefile_id);

    }           

  

    imagedestroy($sourcefile_id);

    imagedestroy($watermarkfile_id);

    

}

backglancer in the hotmail 17-May-2005 11:44


I was about to kill myself....

any one of you trying to merge a SEMI transparent png...

use imagecopy   :)

<?

$flag = imagecreatefrompng('flags/images/flagWhiteFill.png');

$mask = imagecreatefrompng('flags/images/flag_transparent.png');



imagealphablending($flag, 1);

imagealphablending($mask, 1);



imagecopy($flag, $mask, 0,0,0,0,25,43);



Header("Content-type: image/jpeg");

imagepng($flag);

?>



ImageSaveAlpha(resource, bool);   made the transparent color - not transparent... dunno why :)

barbarina_sv at libero dot it 17-May-2005 10:55


I needed to draw a "pointer" image over a map, but had some problems with png image transparency.

So I created a png image with white background (not transparent) and merged it on my map, after defining white color as transparent:



<?php



$src_file = 'source.jpg';

list($src_w, $src_h, $src_t, $src_a) = getimagesize($src_file);



$ptr_file = 'pointer.png'; // must have no transparency, but white background

list($ptr_w, $ptr_h, $ptr_t, $ptr_a) = getimagesize($ptr_file);



// destination image dimensions:

$dst_w = 400;

$dst_h = 200;



// pointer position:

$ptr_x = 195;

$ptr_y = 70;



$srcImage = imageCreateFromJpeg($src_file) or die ('failed imageCreateFromJpg'); 

$dstImage = imageCreateTrueColor($dst_w, $dst_h) or die ('failed imageCreateTrueColor'); 



imageCopyResampled($dstImage, $srcImage, 0, 0, 0, 0, $dst_w, $dst_h, $src_w, $src_h) or die ('failed imageCopyResampled'); 



$ptrImage = imageCreateFromPng($ptr_file) or die ('failed imageCreateFromPng'); 



$ptr_white = imageColorAllocate($ptrImage,255,255,255);

imageColorTransparent($ptrImage,$ptr_white);



imageCopyMerge($dstImage, $ptrImage, $ptr_x, $ptr_y, 0, 0, $ptr_w, $ptr_h, 100) or die ('failed imageCopyMerge');



imageJpeg($dstImage,'',100) or die ('failed imageJpeg');



imageDestroy($srcImage) or die ('failed imageDestroy(1)');

imageDestroy($dstImage) or die ('failed imageDestroy(2)');

imageDestroy($ptrImage) or die ('failed imageDestroy(3)');



?>

ingrid 04-Apr-2005 11:16


I found on the internet about a thousand copies of this "imageCopyMerge" script of Stefan. 



Most of them had a  copyright notice of the copyist added, but none of them had added what a starting user of PHP scripting really needs: The lines to be used in a HTML page, where the result of the script will be visible:



<?php

$sourcefile = "ORIGFILE.jpg";

$insertfile = "watermark.jpg";

$targetfile = "foto.jpg";

$transition = 30;

$pos=7;

require("watermark.php");

mergePix($sourcefile, $insertfile, $targetfile, $pos, $transition);

echo "<img src=\"$targetfile\">";

?> 



I was so lucky to get these lines from someone on the internet, after I posted my question all over the world. 

Most other people that replied, referred to the bookstore. But I had first read halve the (this) PHP manual, and had not found it. 



Just a suggestion, but I know it will help many people getting started with PHP: When you put your scripts here, why not add those few lines needed to incorporate it into a HTML page?

jtacon at php dot net 14-Dec-2004 02:36


This example shows how to use imageCopyMerge to create a water mark function with four random positions (the corners).



<?php

function waterMark($fileInHD, $wmFile, $transparency = 50, $jpegQuality = 90, $margin = 5) {



 $wmImg   = imageCreateFromGIF($wmFile);

 $jpegImg = imageCreateFromJPEG($fileInHD);



 // Water mark random position

 $wmX = (bool)rand(0,1) ? $margin : (imageSX($jpegImg) - imageSX($wmImg)) - $margin;

 $wmY = (bool)rand(0,1) ? $margin : (imageSY($jpegImg) - imageSY($wmImg)) - $margin;



 // Water mark process

 imageCopyMerge($jpegImg, $wmImg, $wmX, $wmY, 0, 0, imageSX($wmImg), imageSY($wmImg), $transparency);



 // Overwriting image

 ImageJPEG($jpegImg, $fileInHD, $jpegQuality);

}



waterMark('myImage.jpg','waterMark.gif');



?>



HTH.



Javier Tac?n.

claudio dot gaetani at gdldesign dot it 09-May-2004 08:04


This function is intended to serve as an example for the "imageCopyMerge"-"ImageCopyResized", "ImageColorTransparent" functions. 

I hope it will help. 

This function pick an image, square cut it resampled at the size requested and finishing merge the result with another one to obtain a circular image result. I have a problem to obtain an thumbnail that respect the colors and at the same time where cutted in a circular form, I hope this solution can gives you a clue to obtain a free form images, I use this one also to create multicutted images.



<?php

$generalsrc="$image"; //the image to resample, resize and iconaize

$final_thumbwidth ="125";

$final_thumbheight ="125";



$abc = imagecreatefromjpeg("$generalsrc"); 

$def = imagecreatetruecolor($final_thumbwidth, $final_thumbheight); 

$src_mx = round((imagesx($abc) / 2)-"0.1"); // middle x point of the image

$src_my = round((imagesy($abc) / 2)-"0.1"); // middle y point of the image

$src_x = ($src_mx * 2);

$src_y = ($src_my * 2);

$src_sq = ($src_x >= $src_y)?$src_y:$src_x; //used to define the best size for a square cut of the image

$pl = ($src_x >= $src_y)?"1":"2"; //define if the image is portait or landscape

$strt_pntx = ($pl=="1")?round(($src_my / 2)-"0. 1"):"0";  //defines the x start point

$strt_pnty = ($pl=="2")?round(($src_mx / 2)-"0. 1"):"0";  //defines the y start point



imagecopyresized($def, $abc, 0, 0, $strt_pntx, $strt_pnty, $final_thumbwidth, $final_thumbheight, $src_sq, $src_sq);



$overlay_img = imagecreatefromPNG("circle_125.png"); //NOTE use png for this

$src_w = "ImageSX($overlay_img)";

$src_h  = "ImageSY($overlay_img)";



$can_img = imagecreatetruecolor($src_w, $src_h);



$black = ImageColorAllocate ($overlay_img, 0, 0, 0);



ImageColorTransparent($overlay_img , $black);



imagecopy($can_img, $def, 0,0,0,0, $src_w, $src_h);

imagecopymerge($can_img, $overlay_img , 0,0,0,0, ImageSX($overlay_img), ImageSY($overlay_img),100); //Imagecopy won't work, you must used imagecopymerge



ImageJPEG($can_img,"merge_$generalsrc",100);



imagedestroy($overlay_img);

imagedestroy($can_img);

ImageDestroy($abc); 

ImageDestroy($def); 



print "<HTML><HEAD><TITLE>test</TITLE></HEAD><BODY>

original:<hr><img src=\"$generalsrc\" width=\"300\"><br><br><br>new:<hr><img src=\"merge_$generalsrc\">

<br>width = $src_x

<br>height = $src_y

<br>mdlw = $src_mx

<br>mdlh = $src_my

<br>sqr = $src_sq

<br>pl = $pl

<br>start point x = $strt_pntx

<br>start point y = $strt_pnty

</BODY></HTML>";

?>

bjorn AT smokingmedia DOT com 26-May-2003 08:10


in addition to stefan's posting:



i found that if you use imagecopymerge with png-24 files with an alpha channel, it doesn't work use imagecopy instead.

it seems that imagecopymerge doesn't respect the alpha channel the way it should (a bug??).



some sample code here to place an image (image.png) on a backgroundcolor or backgroundimage.



<?php



$im = "image.png";

$bg = "ffddee";     // hex representation of the color (i.e. #ffffff for white)

$out = "png";       // or "jpg" for jpg file output

// $backgroundfile = "";  // optional backgroundfile if you don't want to use a color



//

// function to convert hex colorcode to decimal

//



function colordecode($hex){



   $code[r] = hexdec(substr($hex, 0 ,2));

   $code[g] = hexdec(substr($hex, 2 ,2));

   $code[b] = hexdec(substr($hex, 4 ,2));



   return $code;



} // end func colordecode



// create the resource id

$image_id = imageCreateFromPNG($im);



// get image size

$im_X = ImageSX($image_id);

$im_Y = ImageSY($image_id);



// create a truecolor background image of the right size

// or use a background image like this

// $backgroundimage = imageCreateFromPNG($backgroundfile);

$backgroundimage = imagecreatetruecolor($im_X, $im_Y);



// get the desired backgroundcolor:

// don't use this if you want to use a background image

$code = colordecode($bg);

$backgroundcolor = ImageColorAllocate($backgroundimage, $code[r], $code[g], $code[b]);

ImageFilledRectangle($backgroundimage, 0, 0, $im_X, $im_Y, $backgroundcolor);



// merge the two together with alphablending on!

ImageAlphaBlending($backgroundimage, true);

imagecopy($backgroundimage, $image_id, 0, 0, 0, 0, $im_X, $im_Y);



// output the image:

if($output == "jpg"){

   Header( "Content-type: image/jpeg");

   ImageJPEG($backgroundimage);

   }

   else{

       Header( "Content-type: image/png");

       ImagePNG($backgroundimage);

       }



// destroy the memory

ImageDestroy($backgroundimage);

ImageDestroy($image_id);

?>

feisty at feistyenterprises dot com 06-Nov-2002 09:15


Yep, that worked a charm.



Since imageCopyMergeGray() is identical, it works just as well for that.



If you want to convert an image to greyscale, use imageCopyMergeGray() with the same image as source and destination, set the pict to 0, et voila!

jonny at sanriowasteland dot net 29-Sep-2002 02:36


If you need to merge 2 png's (or  presumably 2 gifs) with different color palettes, I have found this is the function to use.  Just set pct to 99, and you are rocking.  With pct set to 100, or imagecopy for that matter, the palette seems to go wonky.  (It probably just uses the palette of the source image. but don't quote me on that).

stefan dot wehowsky at profilschmiede dot de 26-Jul-2001 06:32


This function is intended to serve as an example for the "imageCopyMerge"-function.


I hope it will help some of the less experienced php-coders here.


I wrote it to mark objects of a real estate broker as "sold" by copying the "sold"-picture right into the picture of the house.





<?php





//$sourcefile = Filename of the picture into that $insertfile will be inserted.


//$insertfile = Filename of the picture that is to be inserted into $sourcefile.


//$targetfile = Filename of the modified picture.


//$transition = Intensity of the transition (in percent)


//$pos          = Position where $insertfile will be inserted in $sourcefile


//                0 = middle


//                1 = top left


//                2 = top right


//                3 = bottom right


//                4 = bottom left


//                5 = top middle


//                6 = middle right


//                7 = bottom middle


//                8 = middle left


//


//


function mergePix($sourcefile,$insertfile, $targetfile, $pos=0,$transition=50)


{


    


//Get the resource id?s of the pictures


    $insertfile_id = imageCreateFromJPEG($insertfile);


    $sourcefile_id = imageCreateFromJPEG($sourcefile);





//Get the sizes of both pix    


    $sourcefile_width=imageSX($sourcefile_id);


    $sourcefile_height=imageSY($sourcefile_id);


    $insertfile_width=imageSX($insertfile_id);


    $insertfile_height=imageSY($insertfile_id);





//middle


    if( $pos == 0 )


    {


        $dest_x = ( $sourcefile_width / 2 ) - ( $insertfile_width / 2 );


        $dest_y = ( $sourcefile_height / 2 ) - ( $insertfile_height / 2 );


    }





//top left


    if( $pos == 1 )


    {


        $dest_x = 0;


        $dest_y = 0;


    }





//top right


    if( $pos == 2 )


    {


        $dest_x = $sourcefile_width - $insertfile_width;


        $dest_y = 0;


    }





//bottom right


    if( $pos == 3 )


    {


        $dest_x = $sourcefile_width - $insertfile_width;


        $dest_y = $sourcefile_height - $insertfile_height;


    }





//bottom left    


    if( $pos == 4 )


    {


        $dest_x = 0;


        $dest_y = $sourcefile_height - $insertfile_height;


    }





//top middle


    if( $pos == 5 )


    {


        $dest_x = ( ( $sourcefile_width - $insertfile_width ) / 2 );


        $dest_y = 0;


    }





//middle right


    if( $pos == 6 )


    {


        $dest_x = $sourcefile_width - $insertfile_width;


        $dest_y = ( $sourcefile_height / 2 ) - ( $insertfile_height / 2 );


    }


        


//bottom middle    


    if( $pos == 7 )


    {


        $dest_x = ( ( $sourcefile_width - $insertfile_width ) / 2 );


        $dest_y = $sourcefile_height - $insertfile_height;


    }





//middle left


    if( $pos == 8 )


    {


        $dest_x = 0;


        $dest_y = ( $sourcefile_height / 2 ) - ( $insertfile_height / 2 );


    }


    


//The main thing : merge the two pix    


    imageCopyMerge($sourcefile_id, $insertfile_id,$dest_x,$dest_y,0,0,$insertfile_width,$insertfile_height,$transition);





//Create a jpeg out of the modified picture


    imagejpeg ($sourcefile_id,"$targetfile");


    


}