Just watched this video called How to Remove Ink Stains from Carpet. Do not use this video as a guide to remove ink stains in carpet. It might reduce some of the ink in the carpet but it's guaranteed to create a new stain just a few days later. Glass cleaner is a powerful cleaner that relies heavily on surfactants to break the surface tension so spots can be removed from smooth surfaces, like glass. Glass cleaner is easily removed from non porous surfaces, but carpet is extremely porous. The glass cleaner cannot effectively be removed from the carpet and will start to collect more dirt almost immediately. You will have a bigger stain in the carpet from the glass cleaner then you originally had from the ink spot.
As a professional Carpet cleaner in Tampa FL I can tell you that there is a good way to remove ink from carpet and there are many many terrible ways to remove ink from carpet. This video shows one of the really bad ways. Not only is he going to have a stain from the cleaner that he used to remove the ink but he also damaged the carpet fibers by aggressively scrubbing the carpet. You should never scrub your carpet as vigorously as shown in the video. You can see the carpet actually starts to change shape as he scours it with a wash cloth. When spot cleaning carpet you should only blot the spot, don't scrub, just blot the spot to remove the stain. In most cases if you get an ink stain in the carpet your better off calling in a professional carpet cleaner to get rid the unsightly stain.