Evaluation of JPEG and JPEG2000 effects on remote sensing image classification for mapping natural areas

This study measures how lossy image compression affects digital classification of natural areas. A mixed classification method comprising satellite images and topoclimatic variables for mapping vegetation land cover was used. The results contribute interesting new data about the influence of compression on the quality of the cartography produced, both from a "by pixel" perspective and also regarding the homogeneity of the polygons obtained. When classifications were carried out only with radiometric variables the area classified increases with CR, although the increase is smaller for JPEG2000 formats, especially in fragmented areas. On the other hand, the area classified decreases in classifications which also take into account topoclimatic variables. Overall image accuracy diminishes at high compression levels, although the point of inflection occurs in different places depending on the compression format (highest accuracy for JPEG and fragmented images occurs at lower compression levels). As a rule, the JPEG2000 format gives better results both quantitatively (accuracy and area classified) and visually (images with less "salt and pepper" effect).