In Kdenlive more often than not I had found that many render options are grayed out. Particularly the flv formats. It would say "unsupported video codec" when the mouse is hovered over each crossed and grayed out item. This means that these codes are unavailable in the system. Most probably all codecs are correctly installed but some are in the restricted section hence not installed by default. For example, the extra codecs. To install them first we have to turn on the "multiverse" and "Medibuntu" repos. See medibuntu .org to find out how to add that repo. (Medibuntu is not needed for what we are going to install now, but add it anyways as it has lot of good useful codecs). Then we can proceed to install all possible extra codecs needed by Kdenlive. Depending on the system or OS version the following must be installed libavcodec-extra-52 libavdevice-extra-52 libavfilter-extra-0 libavformat-extra-52 libavutil-extra-49 libpostproc-extra-51 libswscale-