PHP GD Functions

This function copy a part of $src_image onto $dst_image starting at coordinates indicated by $src_x, $src_y with the width $src_width and height $src_height and will be copied at coordinates designated by $dest_x and $dest_y.

This function is identical to imagecopymerge except that when merging it preserves the hue of the source by converting the destination pixels to gray scale before the copy operation.

0 ≤ $pct ≤ 100.

If $pct = 0 is fully grayscale and $pct = 100 is unchanged.

When $pct = 100 this function behaves identically to imagecopy for pallete images, except for ignoring alpha components, while it implements alpha transparency for true colour images.

This function returns TRUE on success or FALSE on failure.


<?php

bool imagecopymergegray ( GdImage $dst_image,
                                             GdImage $src_image, 
                                                      int $dst_x, int $dst_y, 
                                                      int $src_x, int $src_y, 
                                                      int $src_width , int $src_height , 
                                                      int $pct )

where,

$dst_im = The destination image identifier

$src_im = The source image identifier

$dst_x = The x-coordinate of destination point 

$dst_y = The y-coordinate of destination point 

$src_x = The x-coordinate of source point 

$src_y = The y-coordinate of source point 

$src_width = The source width 

$src_height = The source height

$pct = The percentage of the two merged images

?>

$dst_im

The destination image identifier.

$src_im

The source image identifier.

$dst_x

The x-coordinate of destination point.

$dst_y

The y-coordinate of destination point.

$src_x

The x-coordinate of source point.

$src_y

The y-coordinate of source point.

$src_width

The source width.

$src_height

The source height.

$pct

The percentage of the two merged images.

EXERCISE


<?php

// RUN this code several times

echo 'PHP VERSION: ' . PHP_VERSION . '<br><br>';

// $lang = 'pt';
$lang = 'en';

$pct01 = mt_rand(0, 100);

$pt = "Fundo: $pct01%";
$en = "Background: $pct01%";

$seal_img01 = "png/Copyright-red&white.png";

$base_img01 = "png/PNG 044 01.png"; 

$dest_img = "png/PNG 044 01(copyrighted-gray).png"; 

echo $seal_img01; ?><br><br>
<img src="<?php echo $seal_img01; ?>"
 alt="<?php echo $seal_img01; ?>" 
 title="<?php echo $seal_img01; ?>" width="70"><br><br>

<?php echo $base_img01; ?><br><br>
<img src="<?php echo $base_img01; ?>"
 alt="<?php echo $base_img01; ?>" 
 title="<?php echo $base_img01; ?>" width="400"><br><br><br> 
<?php
$id_base01 = imagecreatefrompng($base_img01);

$id_seal01 = imagecreatefrompng($seal_img01);

$seal_w01 = imagesx($id_seal01);
$seal_h01 = imagesy($id_seal01);

$base_w01 = imagesx($id_base01);
$base_h01 = imagesy($id_base01);

$base_x01 = imagesx($id_base01) - $seal_w01 - 5;
$base_y01 = imagesy($id_base01) - $seal_h01 - 55;

imagecopymergegray($id_base01, $id_seal01, 
                                    $base_x01, $base_y01, 
                                    0, 0, 
                                    $seal_w01, $seal_h01, 
                                    $pct01);

imagepng($id_base01, $dest_img);

echo $dest_img . '<br><br>' .$$lang; ?><br><br>
<img src="<?php echo $dest_img; ?>"
 alt="<?php echo $dest_img; ?>" 
 title="<?php echo $dest_img; ?>" width="400">