The in1 read-only property of the SVGFEComponentTransferElement interface reflects the in attribute of the given <feComponentTransfer> element.
An SVGAnimatedString object.
In this example, two <feComponentTransfer> elements are defined in a filter, each with a different in attribute.
<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg">
<filter id="filter1">
<feComponentTransfer in="SourceGraphic">
<feFuncR type="table" tableValues="0 1" />
</feComponentTransfer>
<feComponentTransfer in="BackgroundImage">
<feFuncR type="table" tableValues="0.5 1" />
</feComponentTransfer>
</filter>
<rect
x="20"
y="20"
width="100"
height="100"
fill="red"
filter="url(#filter1)" />
<circle cx="100" cy="100" r="50" fill="blue" filter="url(#filter1)" />
</svg>We can access the in attribute:
const componentTransfers = document.querySelectorAll("feComponentTransfer");
console.log(componentTransfers[0].in1.baseVal); // Output: "SourceGraphic"
console.log(componentTransfers[1].in1.baseVal); // Output: "BackgroundImage"