1. A computing platform, comprising: at least one processor; a communication interface communicatively coupled to the at least one processor; and memory storing computer-readable instructions that, when executed by the at least one processor, cause the computing platform to: receive, via the communication interface, and from a computing device, image data of a deposit item captured by the computing device; determine whether a magnetic ink character recognition (MICR) line of the deposit item is readable based on the image data of the deposit item captured by the computing device; based on determining that the MICR line of the deposit item is readable, process the deposit item for deposit based on the MICR line of the deposit item; and based on determining that the MICR line of the deposit item is not readable: perform an image data lift on the image data of the deposit item to extract information from one or more readable fields of the deposit item; identify a payor of the deposit item based on the information extracted from the one or more readable fields of the deposit item; determine, based on the payor of the deposit item, whether the deposit item is an on-us item, wherein the deposit item is determined to be an on-us item if the deposit item is drawn on a financial institution that operates the computing platform; based on determining that the deposit item is not an on-us item, reject the deposit item; and based on determining that the deposit item is an on-us item: rebuild MICR information for the deposit item based on the payor of the deposit item identified based on the information extracted from the one or more readable fields of the deposit item; and process the deposit item for deposit based on the MICR information for the deposit item rebuilt based on the payor of the deposit item identified based on the information extracted from the one or more readable fields of the deposit item.