DVDFab UHD Ripper, possibly the best 4K Ultra Blu-ray ripper software out there, can convert a 4K Ultra HD movie into MKV/M2TS/MP4 formats, with lossless or 4K HEVC 10-bit or SDR video quality.
The top open-source alternatives to DVDFab UHD Ripper
are HandBrake.
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