Information communication method
An information communication method of transmitting a signal is provided that uses a change in luminance. The method includes determining a plurality of patterns of the change in luminance, by modulating a respective plurality of signals to be transmitted, and transmitting, by a light emitter changing in luminance according to a pattern among the determined plurality of patterns of the change in luminance, a signal corresponding to the pattern. The plurality of signals each includes a header and a body. In the determining, a first body, a first header, and a second body are modulated as one set in stated order. In the transmitting, the light emitter changes in luminance according to, in stated order, a first luminance change pattern corresponding to the first body, a second luminance change pattern corresponding to the first header, and a third luminance change pattern corresponding to the second body.
1. An information communication device, comprising:
a wristband configured to be worn on a wrist of a user;
an image sensor (i) configured to be located on a back-of-hand surface side of the wristband, and (ii) configured to capture a subject that is located in a parallel direction to a back-of-hand surface of the user;
a processor; and
a medium having a computer program stored thereon, the computer program causing the processor to execute operations including
setting an exposure time of an image sensor so that, in an image obtained by capturing a subject by the image sensor, a plurality of bright lines corresponding to a plurality of exposure lines included in the image sensor appear according to a change in luminance of the subject;
obtaining a bright line image including the plurality of bright lines, by capturing the subject changing in luminance by the image sensor with the set exposure time; and
obtaining information by demodulating data specified by a pattern of the plurality of bright lines included in the obtained bright line image.
2. The information communication device according to claim 1 ,
wherein the wristband includes a watch, and
the image sensor is located inside of the watch and captures the subject that is located in a parallel direction to a face of the watch.