| This article introduced an experiment box for taking pictures of corn grain, including main light source,auxiliary light source, a lifter which could adjust the distance of the object to the camera lens and a stage which held the corn grain. Pictures of corn grain were collected by digital camera. Taking the characteristics of shape and color as the research object, this paper researched how to place the auxiliary light source and how to set the light intensity when the lifter was fixed, and how to set the distance when determining the light source. Experimental results showed that, the light spot which came from camera flash affectted feature extraction, the auxiliary light source should be placed in the form of parallel or vertical, and the distance of object to camera lens within the scope of 26~31 cm was better. |
