An apparatus and a method to control manufacturing and feeding of semifinished products in a tyre building process, includes detecting at least one first image representative of a semifinished product; dividing the at least one first image into a plurality of first sub-parts, wherein each one of first sub-parts is composed of a plurality of first portions, each one associated with a respective brightness value; defining a first threshold for the brightness values; making a first comparison between the brightness values of the first portions and the first threshold; as a function of the first comparison, determining for each one of the first sub-parts a first operative parameter representative of a total area occupied in each first sub-part by the first portions associated with a brightness value smaller or greater than the first threshold; making a second comparison between each one of the first operative parameters and a second threshold; and causing the generation of a first notification signal as a function of said second comparison.