LayoutTests/svg/filters/feGaussianBlur-subregion.svg

<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="100" height="100">
  <defs>
    <filter id="Blur" x="-50%" y="-50%" width="200%" height="200%" >
      <feColorMatrix in="SourceGraphic" type="matrix" values="0 1 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 0" result="Transformed"/>
      <feGaussianBlur in="Transformed" x="10" y="10" width="40" height="40" dx="10" dy="10" stdDeviation="10" result="Gaussian"/>
      <feComposite operator="over" in="SourceGraphic" in2="Gaussian" />
    </filter>
  </defs>

  <rect filter="url(#Blur)" x="10" y="10" width="40" height="40" fill="green"/>
</svg>