How to optimize recordings with MP4Fix?

The mp4fix optimize command applies the improvements found by check to your ClonerAlliance UHD Halo recordings. It takes about one second per file, regardless of file size.

Command Options

Option

What it does

-r

Include sub-folders

-n

Preview only - show what would change, write nothing

--copy

Write a new file named <name>.optimized.mp4 and leave the original untouched (needs free space for a second copy)

--device-safe

Keep the file fully compatible with playback on the UHD Halo itself. Use this if you plan to copy the optimized file back to the device.

By default the file is optimized in place. This is fast and needs no extra disk space, which matters when working through a full memory card.

Suggested Workflow

  1. See what is in the folder first:

.\mp4fix-windows-x64.exe check -r "D:\Videos"
  1. Preview the changes without writing anything:

.\mp4fix-windows-x64.exe optimize -n -r "D:\Videos"
  1. Produce one optimized copy and confirm it plays the way you expect:

.\mp4fix-windows-x64.exe optimize --copy "D:\Videos\VID_20260728175011.mp4"
  1. Once satisfied, optimize the whole folder in place:

.\mp4fix-windows-x64.exe optimize -r "D:\Videos"

Note

On macOS, use ./mp4fix-macos with the same commands and options.

What the Output Means

VID_20260728175011.mp4
  Applying 1 improvement:
    - Timeline precision - ...
  Verification: passed
  Optimized (video data untouched)

------------------------------------------------------------
Done.  Optimized 1,  already optimal 0
  • Verification: passed - every change is checked against a set of correctness tests before it is written. If any test does not pass, nothing is written and your file is left exactly as it was.

  • Optimized (video data untouched) - the improvements were applied. Your picture and sound are copied through unchanged.

  • The summary line shows how many files were optimized and how many were already optimal.

Keeping Your Originals

Note

In-place optimization cannot be reversed. If you want to keep the original file exactly as recorded, use --copy, which writes a separate optimized file and leaves your original untouched.

Note

It is safe to stop MP4Fix at any time - even by a power loss. Simply run the same command again and it completes the work automatically. Files that are already optimized are detected and skipped, so running it more than once is always safe.