Ensure "Hardware Acceleration" is enabled in your player settings. This shifts the workload from your processor to your graphics card.
This means your player lacks the x265/HEVC codec. Update to the latest version of VLC. successions01720p10bitblurayhinengx265e install
This can happen if a 10-bit HDR file is played on a non-HDR monitor without "Tone Mapping." Most modern versions of VLC handle this automatically. Ensure "Hardware Acceleration" is enabled in your player