This SVG example illustrates how to apply a blend filter.

BlendFilter.svg

<svg width="400" height="200" xmlns="http://www.w3.org/2000/svg">
  <filter id="idBlendFilter">
    <feOffset in="SourceAlpha" dx="10" dy="10" result="imgOffset" />
    <feBlend in="SourceGraphic" in2="imgOffset" mode="normal" />
  </filter>
  <!-- Original Version -->
  <circle cx="100" cy="100" r="75" fill="none" stroke="gray" stroke-width="10"></circle>
  <!-- Filtered Version -->
  <g style="filter: url(#idBlendFilter)" transform="translate(200, 0)">
    <circle cx="100" cy="100" r="75" fill="none" stroke="gray" stroke-width="10"></circle>
  </g>
</svg>

Output