Различие изображений по пикселям

<?xml version="1.0" encoding="UTF-8" standalone="no"?> <svg xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:svg="http://www.w3.org/2000/svg" xmlns="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" width="512" height="448" viewBox="0 0 512 448" id="svg2" version="1.1" inkscape:version="0.91 r13725" sodipodi:docname="diff-image-pixel.svg"> <title id="title3407">diff-image-pixel</title> <defs id="defs4" /> <sodipodi:namedview id="base" pagecolor="#ffffff" bordercolor="#666666" borderopacity="1.0" inkscape:pageopacity="0.0" inkscape:pageshadow="2" inkscape:zoom="0.98994949" inkscape:cx="453.04944" inkscape:cy="278.57364" inkscape:document-units="px" inkscape:current-layer="layer1" showgrid="true" fit-margin-top="448" fit-margin-right="384" fit-margin-left="0" fit-margin-bottom="0" units="px" inkscape:window-width="1196" inkscape:window-height="852" inkscape:window-x="132" inkscape:window-y="423" inkscape:window-maximized="0" inkscape:snap-bbox="true" inkscape:bbox-nodes="true" inkscape:snap-nodes="true" inkscape:object-nodes="true" showguides="false"> <inkscape:grid type="xygrid" id="grid3347" spacingx="16" spacingy="16" empspacing="2" originx="0" originy="-1.7498462e-005" /> </sodipodi:namedview> <metadata id="metadata7"> <rdf:RDF> <cc:Work rdf:about=""> <dc:format>image/svg+xml</dc:format> <dc:type rdf:resource="http://purl.org/dc/dcmitype/StillImage" /> <dc:title>diff-image-pixel</dc:title> </cc:Work> </rdf:RDF> </metadata> <g inkscape:label="Layer 1" inkscape:groupmode="layer" id="layer1" transform="translate(0,-604.36224)"> <path style="fill-opacity:1;stroke:none" d="M 0 0 L 0 32 L 0 416 L 0 448 L 512 448 L 512 416 L 512 0 L 32 0 L 0 0 z M 32 32 L 480 32 L 480 408 L 400 320 L 354.28516 370.28516 L 208 224 L 32 400 L 32 32 z M 128 320 L 224 320 L 224 416 L 128 416 L 128 320 z " transform="translate(0,604.36224)" id="rect3472" /> <rect y="668.36224" x="288" height="96.000015" width="96" id="rect3488" style="fill-opacity:1;stroke:none" /> </g> </svg>