There are no universally applicable encoding parameters.
The type of movie and its quality are a big variable here. e.g. cel animation, feature movie, lots of grain all play a role here.
The size of your screen and the type of client hardware you use on the largest screen is also of importance.
You want to keep it compatible with the majority of clients, without wasting too much storage space.
In Handbrake, start with the “HQ1080p30 surround” preset.
Then modify it by
- turning off deinterlacing if not necessary (i.e. if the source file is already progressive)
- disabling the denoising filter if the source is clean
- set the encoder preset to “very slow”
- set the Encoder Tune to “Animation” if you have a traditional cel animation movie (NOT for 3D computer graphics animation)
- lower the Constant Quality to 19 or 18, depending on the graininess of the source. (lower number=bigger file size – lots of grain=pick a higher number)
- check the audio tracks and subtitle selections
There are a lot of ways you can vary your process. If you want to go crazy, use Topaz Video AI to denoise and sharpen older movies (requires a hefty computer and lots of testing).
You can also use MKVtoolnixGUI to combine the recoded file with untouched original audio tracks from the source file.
Or employ Subtitle Edit to convert PGS and VOBSUB subtitles into SRT format, which is much more compatible with many client types.
