Process for real-time detection of defects in the surface of a pneumatic tyre comprising the steps of: - placing the pneumatic tyre in rotation about the axis thereof at a predetermined speed; - performing a scan of the surface of the pneumatic tyre by means of the acquisition of linear images, in sequence at a predefined frequency, by a linear digital camera, in order to obtain a sequence of overall images of said overall surface; - selecting a reference image from amongst said overall images; - pre-processing each of said overall images, in order to normalize them in size and/or brightness and/or contrast; - storing each overall image obtained, together with corresponding time information that identifies the instant of the generation thereof; - comparing each overall image temporally successive to said reference image with said reference image, in order to detect the formation of a defect; and - reporting the detection of the formation of a defect together with the instant of the generation of the corresponding overall image, wherein said step of comparing each overall image comprises a step of the cropping of said overall image into portions of predefined dimensions and a step of the alignment of said overall image with respect to said reference image, wherein said comparison step comprises, for each of said portions, a step of converting the value of each pixel into a binary value as a function of a comparison with a predefined threshold, said threshold being a function of the mean value of the pixels in the corresponding portion of the reference image, highlighting regions corresponding to potential defects, the process further comprising a validation step in order to discard any false detections, the process being characterized in that said validation step in turn comprises a step of comparing between: - a superficial extension value expressed in pixels 2 of each area identified as a potential defect; and - a predetermined surface threshold value expressed in pixels 2, discarding the areas identified as a potential defect, wherein said superficial extension value is lower than said surface threshold value. - placing the pneumatic tyre in rotation about the axis thereof at a predetermined speed; - performing a scan of the surface of the pneumatic tyre by means of the acquisition of linear images, in sequence at a predefined frequency, by a linear digital camera, in order to obtain a sequence of overall images of said overall surface; - selecting a reference image from amongst said overall images; - pre-processing each of said overall images, in order to normalize them in size and/or brightness and/or contrast; - storing each overall image obtained, together with corresponding time information that identifies the instant of the generation thereof; - comparing each overall image temporally successive to said reference image with said reference image, in order to detect the formation of a defect; and - reporting the detection of the formation of a defect together with the instant of the generation of the corresponding overall image, wherein said step of comparing each overall image comprises a step of the cropping of said overall image into portions of predefined dimensions and a step of the alignment of said overall image with respect to said reference image, wherein said comparison step comprises, for each of said portions, a step of converting the value of each pixel into a binary value as a function of a comparison with a predefined threshold, said threshold being a function of the mean value of the pixels in the corresponding portion of the reference image, highlighting regions corresponding to potential defects, the process further comprising a validation step in order to discard any false detections, the process being characterized in that said validation step in turn comprises a step of comparing between: - a superficial extension value expressed in pixels 2 of each area identified as a potential defect; and - a predetermined surface threshold value expressed in pixels 2,