feComposite filter

parameters:

operator: arithmetic over in out atop xor
k1 k2 k3 k4 positives values for arithmetic mode
in: first picture
in2: second picture

Tools: change parameters to compose two pictures
         change parameters to compose picture with rectangle colored ( feFlood )
         change parameters to compose picture with feTurbulence filter filled rectangle
Using feGaussianBlur, feOffset, feSpecularLighting and feComposite to create 3D effect lighting

Example of code:

<defs>
<filter id="MyFilter" filterUnits="userSpaceOnUse" x="0" y="0" width="400" height="400">
<feImage xlink:href='#MyImage1' result='pict1'/>
<feImage xlink:href='#MyImage2' result='pict2'/>
<feComposite id='fcp' in='pict1' in2='pict2' operator="arithmetic" k1="0.4" k2="0.4" k3="1" k4="0"/>
</filter>
<image id="MyImage1" width='400' height='400' xlink:href='bateau.jpg'/>
<image id="MyImage2" width='400' height='400' xlink:href='fondu3.jpg'/>
</defs>
<use filter="url(#MyFilter)" x='0' y='0'/>