Image-based light environment distribution in greenhouse

Light is a key environmental factor for crop growth. However the study on light environment in greenhouse has been a difficulty for the researchers because of effects of complex factors from greenhouse structure, orientation, greenhouse glazing and so on. This paper presented an image-based method to investigate the light distribution in real greenhouse by using the computer vision technology. The method was described in detail which including creating a high dynamic range(HDRI), recovering light information from HDRI image, and getting the radiance map of greenhouse light distribution. This radiance map can reflect the distribution of light intensity at different moment and different orientation for one day as well as under different weather case, which can obtain a better fitting result against natural light environment. This research work will not only provide a novel method to obtain complex light distribution, but also provide a more accurate illumination model for incident radiation of crop canopy.