when I run sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libv4l-dev
it shows error, how can I solve it?
libavcodec-dev : Depends: libavutil-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed
Depends: libswresample-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed
libavformat-dev : Depends: libavformat57 (= 7:3.2.10-1~deb9u1) but 7:3.2.10-1~deb9u1+rpt1 is to be installed
Depends: libavutil-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed
Depends: libswresample-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed
libswscale-dev : Depends: libavutil-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed
Depends: libswscale4 (= 7:3.2.10-1~deb9u1) but 7:3.2.10-1~deb9u1+rpt1 is to be installed
E: Unable to correct problems, you have held broken packages.
when I run sudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libv4l-dev it shows error, how can I solve it? libavcodec-dev : Depends: libavutil-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed Depends: libswresample-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed libavformat-dev : Depends: libavformat57 (= 7:3.2.10-1~deb9u1) but 7:3.2.10-1~deb9u1+rpt1 is to be installed Depends: libavutil-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed Depends: libswresample-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed libswscale-dev : Depends: libavutil-dev (= 7:3.2.10-1~deb9u1) but it is not going to be installed Depends: libswscale4 (= 7:3.2.10-1~deb9u1) but 7:3.2.10-1~deb9u1+rpt1 is to be installed E: Unable to correct problems, you have held broken packages.