eshold">-selective-blur <var>geometry</var></a></td>
    <td>selectively blur pixels within a contrast threshold</td>
  </tr>

  <tr>
    <td><a href="command-line-options.html#separate">-separate</a></td>
    <td>separate an image channel into a grayscale image</td>
  </tr>

  <tr>
    <td><a href="command-line-options.html#sepia-tone">-sepia-tone <var>threshold</var></a></td>
    <td>simulate a sepia-toned photo</td>
  </tr>

  <tr>
    <td><a href="command-line-options.html#set">-set <var>attribute value