Image forming system, image forming apparatus, mobile terminal device, and computer-readable non-transitory recording medium

1. An image forming system comprising:

a mobile terminal device; and

an image forming apparatus, wherein

the image forming apparatus includes a display device, (a) generates a preview image corresponding to a target image to be printed, (b) generates an encoded image by encoding the preview image, and (c) displays the encoded image on the display device without displaying the preview image, and the mobile terminal device (a) optically captures the encoded image displayed on the image forming apparatus, (b) acquires the preview image by decoding the captured encoded image, and (c) displays the acquired preview image, and wherein

the image forming apparatus, in accordance with a predetermined conversion rule, (b1) divides the preview image into a plurality of divided images, (b2) generates a plurality of encoded divided images by encoding each of the plurality of divided images, and (b3) generates the encoded image by arranging the plurality of encoded divided images, and the mobile terminal device, in accordance with the conversion rule, (b1) divides the captured encoded image into a plurality of encoded divided images, (b2) generates a plurality of divided images by decoding each of the plurality of encoded divided images obtained from the captured encoded image, and (b3) acquires the preview image by arranging the generated plurality of divided images.

2. The image forming system according to claim 1 , wherein the image forming apparatus notifies the mobile terminal device of the conversion rule.

3. The image forming system according to claim 2 , wherein the image forming apparatus notifies the mobile terminal device of the conversion rule by encrypted communication based on an encryption key unique to the mobile terminal device.

4. The image forming system according to claim 1 , wherein

the image forming apparatus sets a level of brightness or contrast of the display device based on a predetermined set value, and increases the brightness level or contrast of the display device from a first level corresponding to the set value to a predetermined second level higher than the first level when displaying the encoded image.

5. The image forming system according to claim 1 , wherein

the mobile terminal device transmits a request to increase a display size of the encoded image to the image forming apparatus when a size of the captured encoded image is less than a predetermined threshold or when a size of the generated divided image is less than a predetermined threshold, and

the image forming apparatus increases the display size of the encoded image upon receiving the request from the mobile terminal device.

6. The image forming system according to claim 1 , wherein

the image forming apparatus, according to a predetermined conversion rule, (b1) divides the preview image into a plurality of divided images, (b2) generates a plurality of encoded divided images by encoding each of the plurality of divided images, and (b3) sequentially displays a predetermined number of the plurality of encoded divided images on the display device, and

the mobile terminal device (b1) sequentially captures the predetermined number of the encoded divided images in the plurality of encoded divided images, (b2) generates the plurality of divided images by decoding each of the plurality of encoded divided images captured, according to the conversion rule; and (b3) acquires the preview image by arranging the plurality of generated divided images.

7. An image forming apparatus comprising:

a display device; and

a preview processing unit to (a) generate a preview image corresponding to a target image to be printed, (b) generate an encoded image by encoding the preview image, and (c) display the encoded image on the display device without displaying the preview image, wherein

the preview processing unit, in accordance with a predetermined conversion rule, (b1) divides the preview image into a plurality of divided images, (b2) generates a plurality of encoded divided images by encoding each of the plurality of divided images, and (b3) generates the encoded image by arranging the plurality of encoded divided images.

8. A mobile terminal device comprising:

an image capturing device;

a display device; and

a preview support unit that (a) optically captures an encoded image displayed on an image forming apparatus by using the image capturing device, (b) acquires a preview image generated by the image forming apparatus by decoding the captured encoded image, and (c) displays the acquired preview image on the display device, wherein

the encoded image is generated, in accordance with a predetermined conversion rule, (b1) by dividing the preview image into a plurality of divided images, (b2) generating a plurality of encoded divided images by encoding each of the plurality of divided images, and (b3) arranging the plurality of encoded divided images, and the preview support unit, in accordance with the conversion rule, (b1) divides the captured encoded image into a plurality of encoded divided images, (b2) generates a plurality of divided images by decoding each of the plurality of encoded divided images obtained from the captured encoded image, and (b3) acquires the preview image by arranging the generated plurality of divided images.

9. A computer-readable non-transitory recording medium storing a preview support program which causes a computer in a mobile terminal device provided with an image capturing device and a display device to function as a preview support unit that (a) optically captures an encoded image displayed on an image forming apparatus by using the image capturing device, (b) acquires a preview image generated by the image forming apparatus by decoding the captured encoded image, and (c) displays the acquired preview image on the display device, wherein

the encoded image is generated, in accordance with a predetermined conversion rule, (b1) by dividing the preview image into a plurality of divided images, (b2) generating a plurality of encoded divided images by encoding each of the plurality of divided images, and (b3) arranging the plurality of encoded divided images, and the preview support unit, in accordance with the conversion rule, (b1) divides the captured encoded image into a plurality of encoded divided images, (b2) generates a plurality of divided images by decoding each of the plurality of encoded divided images obtained from the captured encoded image, and (b3) acquires the preview image by arranging the generated plurality of divided images.