envi image change detection

view -> 2 horizontal view. load images before and after flooding

view -> link view -> link all 

toolbox -> change detection -> image change workflow

select images from different date -> skip registration

image transform -> pca -> select band 3

save file. Differences are highlighted

toolbox -> change detection -> image change workflow

select images at different date -> skip registration

image difference -> difference of input band -> select band 1

changes in band 1 at different date are reflected

find swir band from band manager and quick stats histogram

flood sediment and mud show up well in swir

plot of difference in swir band before and after flooding

decrease threshold to filter out blue region 

apply smoothing and aggregation

export files. in classes check big decrease. right click and rename to flood impact

reference:

https://www.l3harrisgeospatial.com/docs/imagechangetutorial.html

ENVI 打开报错 JSON_PARSE:UnKnown JSON…

ENVI出现 JSON_PARSE:UnKnown JSON, expecting true, false......_小于等于大于的博客-CSDN博客_envi打开出现json