Analysis of the quality of fused products with corresponding referent original images

摘要

Airborne acquisition of the same part of terrain was done from different heights (500 and 900 meters), by digital matrix camera which collects data about landscape in four wavelengths: three visible channels (V: 0.4-0.5 μm, 0.5-0.6 μm, 0.6-0.7μm) and one near infrared channel (NIR: 0.7-0.9 μm). The set of images of the same terrain which are chosen consists of two RGB images (they are made of: green (G), red (R) and infrared (IR) = color infrared (CIR)) collected from: 500 m (higher space resolution) and 900 m (lower space resolution). With data fusion (used methods are: proncipal components, HIS and method of relative contribution) two products were made: RGB image with higher space resolution inside of the mentioned set of images (higher space resolution (from image collected from 500 m) was implemented in the image collected from 900 m) and RGB image with lower space resolution inside of the set of images (lower space resolution (from image collected from 900 m) was implemented in image collected from 500 m). This action produced two pairs of comparable images: the first one - the product of data fusion with higher spatial resolution and original image with higher spatial resolution (image collected from 500 m); and the second product of data fusion with lower spatial resolution and original image with lower resolution (image collected from 900 m). Namely, the main problem in the analysis of the quality of fused product is how to get reference image. In the majority cases that image needs to be produced, which means that both images are produced (result of fusion and reference image). On the contrary, in this work we provide the analysis of the qualitiy of fused products (on pixel level) on the existing original image basis. Those images are images collected from 500 and 900 m. Changes of images in both directions were monitored, regarding the improving and degradation of spatial resolution. The analysis of qualitiy of fused products was done through statistical parameters (mean, standard deviation, variance, corelation, scatter plot), contrast of images. At the end the existing proposition for protocol for assessment of the quality of fused product basis (Thomas & Wald, 2004) is discussed.