1. An image processing device comprising: one or more processors; and a memory storing computer readable instructions, wherein the computer readable instructions, when executed by the one or more processors, cause the image processing device to: acquire original image data indicating an original image, the original image including M lines of letter strings (the M being an integer of 1 or more) configured of a plurality of letters; and generate processed image data indicating a processed image by executing image processing on the original image data, the processed image having the plurality of letters expressed in an enlarged manner as compared to the original image, the image processing includes: judging whether to execute a first type of enlarging process or execute a second type of enlarging process based on the M lines of letter strings in the original image; in a case of judging to execute the first type of enlarging process, generating a first type of processed image data indicating a first type of processed image, such that a layout of the plurality of letters in the first type of processed image is equal to a layout of the plurality of letters in the original image, and the first type of processed image includes M lines of enlarged letter strings in which the plurality of letters is expressed in the enlarged manner, by executing the first type of enlarging process on the original image data; and in a case of judging to execute the second type of enlarging process, generating a second type of processed image data indicating a second type of processed image, such that a layout of the plurality of letters in the second type of processed image is different from the layout of the plurality of letters in the original image, and the second type of processed image includes N lines of enlarged letter strings (the N being an integer of 1 or more) in which the plurality of letters is expressed in the enlarged manner, by executing the second type of enlarging process on the original image data.