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Before converting files, you should analyze them to understand their format and whether conversion is safe. dovi_convert provides two commands for this: -scan for quick analysis and -inspect for deep verification.

Why scan first?

Not every Dolby Vision Profile 7 file should be converted. Some contain Enhancement Layers with brightness expansion data - converting these produces incorrect results (dark picture, flickering). Scanning identifies:
  • Video format - HDR10, HDR10+, Dolby Vision (and which profile)
  • FEL classification - MEL, Simple FEL, or Complex FEL
  • Conversion safety - Whether the file is safe to convert
The -convert and -batch commands automatically scan files before processing and warn you about risky conversions. Running -scan separately gives you an overview without starting any conversion.

The -scan command

Scans files to identify their video format and FEL status.

Basic usage

dovi_convert -scan                   # All MKV files in current directory
dovi_convert -scan "Movie.mkv"       # Specific file

Recursive scanning

Scan subdirectories with the -r flag:
dovi_convert -scan -r                # Recursive (default depth: 5)
dovi_convert -scan -r 2              # Recursive (depth: 2 folders)

Understanding the output

The scan displays color-coded results for each file:
ColorClassificationMeaning
GreenMELNo enhancement data. Safe to convert.
CyanSimple FELNo brightness expansion detected. Usually safe.
RedComplex FELActive brightness expansion. Conversion not recommended.
Non-Profile 7 files (HDR10, SDR, etc.) are also identified but cannot be converted by this tool.

How -scan works

The scan samples 10 timestamps across the file and analyzes the RPU (Reference Processing Unit) metadata at each point. It checks for brightness values that exceed the Base Layer’s capability - an indicator of Complex FEL.
Sampling is fast but not exhaustive. A file might have brightness spikes in sections the scan didn’t sample. For definitive results, use -inspect.

Terminology

MEL (Minimal Enhancement Layer)

The Enhancement Layer exists but contains no useful data. This is the most common type. Converting is completely safe - you lose nothing.

Simple FEL (No brightness expansion)

The Enhancement Layer contains some data (film grain, minor color adjustments), but does not expand brightness. Converting is generally safe - you lose minor enhancements, but the picture remains correct.

Complex FEL (Brightness expansion)

The Enhancement Layer actively elevates brightness beyond the Base Layer. Converting produces incorrect tone mapping. These files are skipped by default. For more details on FEL types and their implications, see Before You Start.

The -inspect command

Performs a full frame-by-frame analysis of the entire file. Use this when you need definitive confirmation.

When to use -inspect

  • Verify a Simple FEL verdict from -scan
  • Get absolute certainty before converting a file
  • Investigate files that -scan couldn’t fully classify

Basic usage

dovi_convert -inspect "Movie.mkv"

How -inspect differs from -scan

Aspect-scan-inspect
SpeedFast (samples 10 points)Slow (reads entire file)
AccuracyHigh (may miss isolated spikes)Definitive
Batch supportYesNo (single file only)
-inspect reads the entire file frame-by-frame. For a typical 50-80 GB movie, this takes several minutes. It’s not suitable for batch operations.

Interpreting results

After analysis, -inspect reports:
  • Whether brightness expansion was detected (the primary concern)
  • The peak brightness values found in the metadata
  • A verdict confirming if the file is safe to convert
If -inspect says the file is safe but -scan said Complex FEL, trust -inspect - it analyzed the entire file rather than sampling.

Automatic scanning in other commands

You don’t always need to run -scan manually. Both -convert and -batch perform the same analysis automatically:
  • Complex FEL files are skipped by default (use -force to override)
  • Simple FEL files trigger a confirmation prompt
This means you can safely run -convert on any file - the tool warns you before doing anything risky.

Next steps