How to enable sparse image in android

[Kishore Poojari]

Hello All , 

    When I build android lollipop 5.0.0.1 , at the end system_sparse.img is not converted to system.img , 

following error is show

if [ true = true ]; then \
        simg2img out/target/product/evk_6sl/system_sparse.img out/target/product/evk_6sl/system.img; \
        fi
/bin/bash: line 1: simg2img: command not found
make: *** [out/target/product/evk_6sl/system_sparse.img] Error 127
make: *** Deleting file `out/target/product/evk_6sl/system_sparse.img'

How to enable sparse image in android....?

Is their any patch to apply...?

Regards,

Kishore P