The core metadata containing frame-by-frame or scene-by-scene dynamic tone-mapping instructions.

If you do not have Dolby tools or original mastering files:

The tool will strip the enhancement layer and inject the RPU (dynamic metadata) into the base layer.

Fixes playback on non-disc players.

Before diving into the steps, it is essential to understand the technical architecture that dictates why this conversion is necessary for home theater enthusiasts.

# Step 2: Extract the RPU metadata from the HEVC stream # dovi_tool reads the stream and pulls out the RPU cmd_rpu = ["dovi_tool", "-m", "2", "extract-rpu", self.temp_hevc, "-o", self.temp_rpu] subprocess.run(cmd_rpu, check=True)

: This type of EL contains only the Reference Picture Unit (RPU)—the dynamic metadata—and no additional picture information. For MEL sources, converting from Profile 7 to Profile 8.1 is a lossless process. You are simply relocating the RPU to be part of a single-layer stream, resulting in a file that is functionally identical in quality to the original. For example, a P7 MEL file converted to P8.1 will have no video data lost; you are simply changing where the metadata is stored in the video stream.

You must split the original Profile 7 MKV file into its raw components. Use FFmpeg or MKVToolNix to extract the video track.

Convert Dolby Vision Profile 7 to Profile 8.1: New & Easiest Methods [2026 Guide]

Note: ffmpeg alone cannot fully convert profiles reliably to a Dolby-compliant Profile 8 in many cases; Dolby tools or licensed third-party solutions are normally required.