Is it possible to specify that as SVG image should produce output in CMYK? If so, is it a big task? What if the image has its colours specified in RGB, is it difficult to convert them to CMYK?
SVG supports ICC colors, using ICC color profiles, which would let you do what you need, but it's not yet supported by any browser :(
SVG 2.0 adds support for unmanaged colors allowing you to specify a CMYK color with an sRGB fallback:
<circle fill="#CD853F device-cmyk(0.11, 0.48, 0.83, 0.00)"/>
You can also use icc-named-color() to specify a spot color which would be defined in a linked ICC color profile.
At this time, this is still a working draft spec, but some tools may support it such as Apache Batik's svgcolor12 branch.
来源：https://stackoverflow.com/questions/3405689/svg-image-with-cmyk-colours-is-it-possible