winff 1.5.5-6 (riscv64 binary) in ubuntu groovy

 WinFF is a graphical user interface for FFmpeg or avconv. It will convert
 almost any video file that FFmpeg or avconv will convert. WinFF does multiple
 files in multiple formats at one time. You can, for example, convert
 mpeg's, flv's, and mov's into avi's (or DVD/VCD format or MPEG or 3gp
 etc.) all at once.
 .
 WinFF provides a variety of preset conversion settings for
 common formats and devices. These presets are intended to hit the
 "sweet spot" for each individual codec. They have been written with a
 tip of the balance to quality.
 .
 For most presets to work, it is necessary to have the unstripped version
 of the libavcodec package, which can be obtained by installing
 libavcodec-extra as suggested by the WinFF suite. It might be necessary
 to enable additional repositories to find that package.