These requirements do change quite frequently.

apt-get install perl libwww-perl libxml-perl libxml-simple-perl atomicparsley

Add this to /etc/apt/sources.list (for Jessie only):

deb http://ftp.uk.debian.org/debian jessie-backports main

then

apt-get update
apt-get install ffmpeg

and

crontab -e

min hour day/month month day/week command
15 0 * * * /usr/bin/local/get_iplayer --pvr --quiet -c 'echo "$(date)    <name> <episode>" >> /home/slack/log/iplayer' 2>> /tmp/get_iplayer.log