A method for realising ceramic slabs or tiles, comprising the following steps: laying a soft layer (SL) of granular or powder ceramic material on a support plane (P); pressing the soft layer (SL) in order to obtain a compacted layer (CL); firing the compacted layer (CL); prior to the pressing, applying an identification mark (M) onto the soft layer (SL), the identification mark (M) having an optical contrast with respect to the soft layer (SL), so as to enable an optical detection of the mark (M); subsequently to the pressing, acquiring an image of the mark (M); processing the image of the mark (M) detected so as to control one or more operating steps preceding and/or subsequent to the pressing of the soft layer (SL); wherein it comprises the following steps: the step of acquiring an image of the mark (M) comprises acquiring an image of a zone containing the mark (M); the step of processing the image of the mark (M) comprises detecting a position of the mark (M) in the image acquired subsequently to the pressing, i.e. a final position of the mark (M); carrying out a comparison between the final position of the mark (M) and an initial position of the mark (M) preceding the pressing; detecting a displacement vector comprising a length and direction datum of a displacement of the mark (M) from the initial position to the final position. laying a soft layer (SL) of granular or powder ceramic material on a support plane (P); pressing the soft layer (SL) in order to obtain a compacted layer (CL); firing the compacted layer (CL); prior to the pressing, applying an identification mark (M) onto the soft layer (SL), the identification mark (M) having an optical contrast with respect to the soft layer (SL), so as to enable an optical detection of the mark (M); subsequently to the pressing, acquiring an image of the mark (M); processing the image of the mark (M) detected so as to control one or more operating steps preceding and/or subsequent to the pressing of the soft layer (SL); wherein it comprises the following steps: the step of acquiring an image of the mark (M) comprises acquiring an image of a zone containing the mark (M); the step of processing the image of the mark (M) comprises detecting a position of the mark (M) in the image acquired subsequently to the pressing, i.e. a final position of the mark (M); carrying out a comparison between the final position of the mark (M) and an initial position of the mark (M) preceding the pressing; detecting a displacement vector comprising a length and direction datum of a displacement of the mark (M) from the initial position to the final position. the step of acquiring an image of the mark (M) comprises acquiring an image of a zone containing the mark (M); the step of processing the image of the mark (M) comprises detecting a position of the mark (M) in the image acquired subsequently to the pressing, i.e. a final position of the mark (M); carrying out a comparison between the final position of the mark (M) and an initial position of the mark (M) preceding the pressing; detecting a displacement vector comprising a length and direction datum of a displacement of the mark (M) from the initial position to the final position. <EOS>