1. A carried item region extraction device comprising: a CPU; and a non-transitory computer readable recording medium storing a program; wherein: the CPU is configured to implement: a string region processing configured to extract a string region including a string of a carried item from image information; and a carried item region processing configured to extract a carried item region including a carried item from said image information on the basis of said string region; said string region processing comprises: an edge component extraction configured to extract an edge component of said image information; a string region line pair component extraction configured to extract an edge line pair component on the basis of said edge component; and a string region extraction configured to extract the string region on the basis of said edge line pair component; and said string region line pair component extraction comprises: an edge line component generation configured to generate an edge line component on the basis of said edge component by using a predetermined width for said edge line component; and an edge line pair component extraction configured to extract an edge line pair component on the basis of said edge line component.