The smartphone camera detects the light peculiar to the step and sounds a warning.
This app is not all-purpose, please be sure to use other confirmation methods together.
It would be greatly appreciated if we could help a little with the complement of guide dogs and unfamiliar roads.

● Operation
·start
1. Launch the app
2. Start detection: Move the camera forward or up and down.
* Before use, it is necessary to adjust the visible side. (Detection range, walking speed, etc.)

・ End
1. Home button
2. Delete app history

● Operating sound (every 0.5 seconds, it may be slower depending on the smartphone.)
And: There is no light peculiar to the step (vibration: 0.02 seconds)
Po: There is light peculiar to the step in the distance (vibration: 0.02 seconds)
Chord: Light peculiar to the step is nearby (vibration: 0.50 seconds)
Silence: It is stopped or the shooting conditions are not met. (Vibration: None)
* Consider bone electric earphones so that the sound does not leak to the surroundings.

● Detection accuracy (personal feeling): Downward 45 degrees, 10 times Test
Harbor: Sunny
Straight false alarm: 3%
Quay warning: 80%
Light alarm: 15%
Stairs warning: 10%

Abandoned station: Sunny (not tested at regular stations)
Straight false alarm: 10%
Orthogonal to the edge of the home: 36% (11 times)
Diagonal to the edge of the home: 60%

● Battery life:
Used for 1 hour on Nexus 5x. (100% → 40%)
Nexus5x Performance: 1.8 GHz Qualcomm Snapdragon, Battery: 2,700mAh, Use: 1 year
If you use it for a long time, please use a mobile battery together.
* There is no battery level detection function.
It is recommended to delete the application history after use.
(You cannot stop with the home button, and the battery may continue to be consumed.)

● Impact on the surroundings
Since it is detected only by the light entering the camera,
Nothing radiates from smartphones (sound, electromagnetic waves, flash, etc .: excluding operating noise)
* Because you use the camera, please consider the privacy of those around you.

● Adjustment before use (Since the app is about 20MB, please adjust it in a place where Wifi is connected)
* Setting items are in the ":" on the upper right. There are two pairs of UP and DOWN with the same name. The numerical value is the set value.
-Adjust the camera angle and screen angle.
CameraAngle: Press until the image matches the smartphone screen
・ Determine the detection range
AreaAngle: Press until the trapezoid of the thick frame is in front
* Adjust the camera angle according to the height of the person using the app. (I feel that 40 to 60 degrees is good, please change it when there are many false positives and no alarms)
AreaOffset: Change the location of the trapezoid
AreaSize: Change the size of the trapezoid
AreaSlope: Change the angle of the trapezoid
・ Adjusted to work when walking
WalkWait: Adjusted so that the central "+" is between the large and small circles at the walking speed of the user.
AlertAreaCount: Adjust the size of the step to warn
Vibration: Switching between vibration and warning sound
* The set value will be saved, but it cannot be retrieved. Write it down somewhere else.

To return to the default value, delete the data of the application from the setting screen of the smartphone.

● Use of neck holder: Personal feeling
I feel that using a neck holder instead of holding it will double the accuracy. (False detection, no alarm, etc.)
https://www.donya.jp/item/74364.html (used for operation check)
https://www.edelkrone.com/p/503/povie (Operation has not been confirmed)

● False alarms and no alarms currently being confirmed
▲ False alarm in the alarm range (conditions that warn you though there is no step)
・ Moving objects and moving shadows (animals and people are moving within the warning range, they are behind the sun, etc.)
・ There are gloss, fine patterns, and large spots (fallen leaves, etc.) on the ground.
・ I changed the walking direction
・ The ground is dark (evening in the evening, at night, under black clouds)
・ The camera has rotated more than 10 degrees

▲ No alarm (conditions that cannot be detected)
-There is no color difference between the back and front of the step (concrete and new gravel, etc.)
・ I approached the step diagonally
・ The light peculiar to the step is small (the size of my terminal is about 40 cm or less)
・ The step is not within the alarm range when shooting
・ The same color when grayscaled (dark gray, green, purple, etc.)

● Restrictions
Large walls, lakeshores, and overpasses may ring even in the distance, and the warning may stop when approaching.
If the camera shakes, it will malfunction (heel landing shock, etc.)
No alarms and false alarms occur frequently in dark places and under fluorescent lights. (Is it the effect of camera noise or shutter?)
The number of detection points varies depending on the number of compatible pixels of the smartphone. (It is determined by the application's own calculation, not the numerical value in the catalog)
The camera will stop at high temperatures, so be careful not to exceed the temperature under the scorching sun. (Use shade, etc.)
I don't expect to run.

● If there is no sound
-Unmute the system volume setting.
-Unmute the volume setting of the application.
-Delete the application data from the smartphone setting screen.

● Completeness: Personal feeling
60%
・ About the release with low degree of completion
The demand for use on smartphones is unknown,
I heard that devices with alternative technologies will be released soon.
Did this app throw a stone in the development method? I would be happy if

This application does not have a function to save or send images on the smartphone itself.
This application will be open to the public for about 6 months.
Due to the creator's convenience, this application may be suspended from publication in a hurry.
Due to various reasons, there are no plans to make an iOS version.

It is unknown to create a commercial version.