像素每像素图像，透明变成黑色

Question

I read a couple of thing about this, but I can't figure how to put it in my code.

Here it is :

function go($image) {
    // Open the image
    $getimage=imagecreatefrompng($image);
  //Get the width/height
   $w = imagesx($getimage);
   $h = imagesy($getimage);
   //init Count variable, when it reach the width, skip a line
   $count = 0;
   // For each line
   for($y=0;$y<$h;$y++) {
       // For each column
      for($x=0;$x<$w;$x++) {
        $rgba     = imagecolorat($getimage, $x, $y);
        $r = ($rgba >> 16) & 0xFF;
        $g = ($rgba >> 8) & 0xFF;
        $b = $rgba & 0xFF;
        $a     = ($rgba & 0x7F000000) >> 24;
        echo '<div class="pix" style="background-color: rgba('.$r.', '.$g.', '.$b.', '.$a.');"></div>';
        $count++;
        if($count==$w) {echo '<br>'; $count = 0; }

      }
   }
   echo $pixel_gen;

}

If oyu want to see what it looks like, clic here: http://narks.xtreemhost.com/

And double-click on any icon, popup will appear. (Note: dbl-clinking on any icon will show the same image (I didnt fixed this yet)

Any idea how i can make the black pixel appear like the real pixel with alpha) ?

Thanks for your help!

EDITED (New code, i put only the first lines since i want to save space)

function go($image) {
    // Open the image
    $getimage=imagecreatefrompng($image);
    imagealphablending($getimage, false);
    imagesavealpha($getimage, true);

  //Get the width/height
   $w = imagesx($getimage);
   $h = imagesy($getimage);
[...]

To see what it looks like now, visit the website above and double-click on an icon.

EDIT 2 I just tried (for a test) with :

$getimage=imagecreatefrompng('iconDB/lib/chat_fav_48.png');
imagealphablending($getimage, false);
imagesavealpha($getimage, true);

header("Content-type: image/png");
imagepng($getimage);
imagedestroy($getimage);

and then with

$getimage=imagecreatefrompng('iconDB/lib/chat_fav_48.png');

header("Content-type: image/png");
imagepng($getimage);
imagedestroy($getimage);

The first is okay and the second make pixels black. So it is when i get each pixel's RGB colors and when I display it. Anyone see a mistake there?

Answer 1

Here is the correct working code, in order to complete this question.

function go($image) {
 // Open the image
 $getimage=imagecreatefrompng($image);
 imagealphablending($getimage, true);
 imagesavealpha($getimage, true);

  //Get the width/height
   $w = imagesx($getimage);
   $h = imagesy($getimage);
   //init Count variable, when it reach the width, skip a line
   $count = 0;
   // For each line
   for($y=0;$y<$h;$y++) {
    // For each column
      for($x=0;$x<$w;$x++) {
    // Get the image color for this pixel
  $rgba     = imagecolorat($getimage, $x, $y);
  $r = ($rgba >> 16) & 0xFF;
  $g = ($rgba >> 8) & 0xFF;
  $b = $rgba & 0xFF;
  $a = ($rgba & 0x7F000000) >> 24;
  //Calculating the correct Alpha value for rgba display in css
  $a = (127-$a)/127;
  echo '<div class="pix" style="background-color: rgba('.$r.', '.$g.', '.$b.', '.$a.');"></div>';
  $count++;
  if($count==$w) {echo '<br>'; $count = 0; }

      }
   }
   echo $pixel_gen;

}

I hope it will be useful for someone