Watermark on animated gif with php

Question

I need a function that adds a watermark to an animated gif. How I can do that with PHP and ImageMagick?

This is my code, but it doesn't work.

function IMagickWatermark($sf, $sfDest, $sfLogo, $sGravity='southeast'){
        //$sCmd = "composite -compose bumpmap -gravity $sGravity $sfLogo \"$sf\" $sfDest";
        $sCmd = "convert \"$sf\" -coalesce -gravity south -draw 'image over 0,0 0,0 \"$sfLogo\"' \"$sfDest\"";
        exec($sCmd);
        return 1;
    }
$sf = $_SERVER['DOCUMENT_ROOT']."/test/source.gif";
$sfDest = $_SERVER['DOCUMENT_ROOT']."/test/dest.gif";
$sfLogo = $_SERVER['DOCUMENT_ROOT']."/test/logowithtext.gif";
IMagickWatermark($sf, $sfDest, $sfLogo, $sGravity='SouthEast');

Answer 1

Try this:

$animation = ani.gif; 

$watermark = logo.png; 

$watermarked_animation = "morph.gif"; 

$cmd = " $animation -coalesce -gravity South ". 
" -geometry +0+0 null: $watermark -layers composite -layers optimize "; 

exec("convert $cmd $watermarked_animation "); 

Answer 2

<?php
shell_exec('for i in sphere*.gif; do convert $i  -font Arial -pointsize 20 \
      -draw "gravity south \
             fill black  text 0,12 \'Copyright\' \
             fill white  text 1,11 \'Copyright\' " \
      wmark_$i; done');

shell_exec("convert   -delay 20   -loop 0   wmark_sphere*.gif   animatespheres.gif");
$f = fopen("animatespheres.gif", 'rb');
fpassthru($f);
fclose($f);
?>

if you need to debug, remove the fopen,fpassthru,fclose lines and add echo's for the shell_execs.