Today image capture did not work again, though it had worked 3 days before. I also found that red indicator light on the front pannel of SENSORAY was not turned on, which had been turned on 3 days before (you can find SENSORAY on the floor near Pianosa). Possible reason that it did not work again was I restarted Pianosa last night. Anyway, it works now. Here I report what I did to make it work.

I ran thes commands in shell, following the instruction of the manual of SENSORAY 2253 (Page 5; link or you can find the manual in /users/sensoray; I put it there). 

> cd /users/sensoray/sdk_2253_1.2.2_linux

> make all

> sudo make install

> modprobe s2253

Then the red light got turned on, and image capture worked.

If you recieve an error like "No such file or directory: /dev/video0" at the beginning of the error message when you run image capture scripts from the medm screen, or if you notice that the red indicator light of SENSORAY is not on, this procedure could help you.