I need to set up ffmpeg however get the message under. How can I repair this ?

(base) h@cheemc52:~/opencv/construct$ sudo apt-get set up ffmpeg
Studying package deal lists... Achieved
Constructing dependency tree
Studying state info... Achieved
Some packages couldn't be put in. This may occasionally imply that you've
requested an not possible scenario or in case you are utilizing the unstable
distribution that some required packages haven't but been created
or been moved out of Incoming.
The next info could assist to resolve the scenario:

The next packages have unmet dependencies:
 ffmpeg : Relies upon: libavcodec56 (>= 10:2.6.9) however it's not going to be put in
          Relies upon: libavdevice56 (>= 10:2.6.9) however it's not going to be put in
          Relies upon: libavfilter5 (>= 10:2.6.9) however it's not going to be put in
          Relies upon: libavformat56 (>= 10:2.6.9) however it's not going to be put in
E: Unable to right issues, you've gotten held damaged packages.