feConvolveMatrix filter primitive

parameters:

order: two positives integer for x and y

kernelMatrix: order_x*order_y values to compute pixel

targetX, targetY: positives integer to center effect

preserveAlpha: true false

bias: value to add

divisor: integer, by default sum of terms of kernelMatrix

edgeMode: duplicate wrap none

in: picture to modify

Example of code:

<defs>
   <filter id="MyFilter" filterUnits="userSpaceOnUse" x="0" y="0" width="400" height="400">
      <feImage xlink:href='puzzle.jpg' result='image1'/>
      <feConvolveMatrix in='image1' order="3 3" targetX="0" targetY="0" edgeMode="duplicate" 
           kernelMatrix="1 2 3 2 3 4 3 4 5" preserveAlpha='false'/>
   </filter>
</defs>
<use filter="url(#MyFilter)" x='0' y='0'/>

Tool: you can modify x_order, y_order, kernelMatrix an see effect on picture of your choice.
Example:

FrontPage feColorMatrix feComponentTransfer feSpecularLightning feDiffuseLightning feSpotLight feDistantLight fePointLight feFlood feImage feTurbulence feTile feMerge feBlend feComposite feGaussianBlur feMorphology feConvolveMatrix feDisplacementMap feOffset