Path animation Turner

<svg width="400" height="400" xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2000/svg">
<defs>
<filter height="200%" width="200%" y="-50%" x="-50%" id="svg_3_blur">
   <feGaussianBlur stdDeviation="4" in="SourceGraphic"/>
</filter>
<mask id="mmask">
   <path filter="url(#svg_3_blur)" id="svg_1" fill="#FFFFFF">
   <animate attributename="d" repeatcount="1" begin="cover.mousedown" dur="24s" values="
m200,200l0,0l0,0l0,0l0,0l0,0l0,0l0,0l0,0z;

m100,100l100,0l100,0l0,100l0,100l-100,0l-100,0l0,-100l0,-100z;

m100,100l100,-100l100,100l100,100l-100,100l-100,100l-100,-100l-100,-100l100,-100z;

m300,300l-100,-300l-100,300l300,-100l-300,-100l100,300l100,-300l-300,100l300,100z;

m100,300l200,-200l-200,0l200,200l0,-200l-200,200l200,0l-200,-200l0,200z;

m100,100l100,0l100,0l0,100l0,100l-100,0l-100,0l0,-100l0,-100z;

m0,400l200,0l200,0l0,-200l0,-200l-200,200l-200,-200l0,200l0,200z;

m200,200l0,0l0,0l0,0l0,0l0,0l0,0l0,0l0,0z;

m100,100l100,0l100,0l0,100l0,100l-100,0l-100,0l0,-100l0,-100z"/>
  </path>
</mask>
</defs>
 <g>
  <title>Turner Tourné</title>
  <image xlink:href="http://ilsetelles.fr/wp-content/uploads/fort-vimieux.jpg" id="svg_4" height="519.1715" width="757.8395" y="-14.76541" x="-297.58645"/>
  <image xlink:href="https://upload.wikimedia.org/wikipedia/commons/0/0d/Joseph_Mallord_William_Turner_-_Fishermen_at_Sea_-_Google_Art_Project.jpg" id="cover" height="408.67151" width="549.92865" style="mask:url(#mmask);" y="-9.5919" x="-9.57338"/>
 </g>
</svg>