METHOD AND DEVICE FOR INSPECTING IMAGE

Disclosed is a method and device for inspecting defects of the image on a print in the form of a web which is transported in its longitudinal direction. Data each representative of the density of each picture element of a reference print are stored in a memory in accordance with predetermined addresses. Thereafter, data each representative of the density of each picture element of a sample print are derived and compared in density one picture element by one picture element with the reference data read out from the memory, whereby whether or not the sample print has any defect is determined. In this case, because of a web transport system or because of printing sheet itself, data are deviated with respect to each other so that this deviation must be corrected or compensated for. The present invention provides a method and device for inspecting the printing image while correcting or compensating for the deviation between the two data.