Seikaisuru Kado (BD 1080p FLAC)

Thanks but smaller version please. It doesn't need FLAC. And maybe 720p?

@Stultus I know fuckall about encoding, so you're not gonna get that from me. Maybe someone else will pick it up, who knows.

@Stultus: Do it like this after download (ffmpeg in linux command line, windows probably the same):

 $ cd Seikaisuru\ Kado
 $ for file in *.mkv; do ffmpeg -i "$file" -map 0 -map_metadata 0 -vf scale=-2:720 -c:v libx265 -crf 24 -preset veryslow -c:a libopus -scodec copy "${file%(*}(BD720p x265 opus).mkv"

for a folder with nice small converted files; all info intact. Delete old files after success (and seeding them).

Opus? HEVC? Please do not use the above command the raws you used are already using a lossy encode, if you encode them again you are just fucking with the quality by not encoding from the BDMVs. Opus doesn't support 44.1khz and is aimed at low bitrates, you want to be using aac, preferably QAAC but even say -c:a aac -b:a 256k will be good enough for most people. The ffmpeg aac encoder has improved a lot recently. Encoding audio from FLAC to a lossy codec such as AAC is perfectly fine.

At the very least though, if the source is using 24-bit FLAC I would re-encodeit down to 16-bit to shave a lot of the filesize off without losing any noticable details to the human ear.
So make a new folder and place all the videos in there and run this to re-encode 24-bit flac into 16 bit. Change "Flac" to "aac" and -sample_fmt s16" to "-b:a 256k" if you want to do a quick and easy aac encode.

FOR %f IN (*.mkv) DO call ffmpeg.exe -i "%f" -map 0 -c:v copy -c:a flac -sample_fmt s16 "../%f"

@MetalicBox: Do you really think that a guy who complains about the 18.7 GB cares fuck all about the quality? I know full well about the quality loss. This is for cranking out a somewhat acceptable version with all meta info intact. Chances are that Stultus uses a hardware player which is able to do HEVC, but not 10-bit H.264.

Your arguments are otherwise correct, and thanks for posting a Windows version.

Please, take Hakuouki Sekka-roku BD too.