Sunday, December 15, 2013

UPDATED: Converting Magic Lantern MLV files to RAW on OSX

Enjoy this tiger at the 2013 New York Marathon from a video I'm cutting.
UDATE: Check out this solution for directly converting MLV to cDNG or DNG.

I've had some difficulty converting files from the latest Magic Lantern raw video format (MLV) into something that I can post-process (like DNG or cDNG files) on my Mac.

After working on it a month or so ago, I gave up and eventually installed windows via VMWare Fusion so that I could get mlv_dump working. I was successful in windows and was able to mass convert a bunch of footage into RAW files which was compatible with my workflow (currently using RAWMagic on OSX, etc.).

Well, somewhere a few weeks ago I deleted my VMWare Fusion partition and lost the notes I had on the windows box detailing how to do the conversion. I didn't want to go through the trouble of installing windows again so I gave another stab at converting MLV files on OSX… and I got it to work!

So I want to share my findings, both for my future self, as well as anyone else out there using the new format with OSX.

First off, download the pre-compiled binary that user marekk has generously posted on the Magic Lantern forum from his Dropbox:

I copied this file into the same directory as my MLV files and unzipped it.

Open a Terminal window and cd into the folder where you have your MLV files (and now mlv_dump).

Drag the (unzipped) mlv_dump file from Finder into the Terminal window and add the following text:

-o outputfilename.RAW -r mlvfilename.MLV

So now you should have something like the following in your Terminal window:

<path for your MLV files>/mlv_dump -o outputfilename.RAW -r mlvfilename.MLV

Of course, replace outputfilename.RAW with whatever name you want to call the RAW file to be generated. And replace mlvfilename.MLV with the name of the MLV file that your camera produced.

Once you hit Enter, it should start processing and you'll get a RAW file. Voila! Continue your workflow from there.

Hope this helps folks to ease the transition to using MLV.

If someone savvier than me with OSX can think of a method to batch process a bunch of MLV files into RAW, please let me know! Leave a comment below, thanks!


  1. Hello John,

    Thank you for your post, although the whole process seems incredibly difficult compared to RAWMagic, it's the first time I've been able to get any results out of the dreaded mlv_dump!

    My next question would be, how do you get mlv_dump to convert all the .mlv files directly to DNG or CDNG (not even sure if there is a difference between the two)?

    Many thanks for all your've seriously made my day!

  2. Hi Kays, I'm working on it! But for now, I'm really happy that I'm not stuck with a bunch of MLV files that I can't process. Thanks for your note, I'm glad I could help!

  3. i only get the frame file, no dngs's get created, can you tell me what im doing wrong.

    heres my process.
    i put all my MLV files on my desktop in a folder called mlv
    open up terminal. desktop the enter mlv then enter
    3. ./mlv_dump --dng M15-0120.MLV then enter

    Process says its done but only get a frame file

  4. Hi John, thank you for your work :)
    When i write ./mlv_dump --dng M17-1615.MLV
    it says:
    MLV Dumper v1.0

    [i] Mode of operation:
    - Input MLV file: 'M17-1615.MLV'
    - Convert to DNG frames
    - Output into 'M17-1615_frame_'
    [i] File M17-1615.MLV opened
    [i] File M17-1615.IDX opened (XREF)
    [i] XREF table contains 843 entries
    [i] Processing...
    [E] Missing file header
    [i] Processed 0 video frames
    [i] Done

    What means missing file header?
    Thank you

  5. @saltyvisions: very weird, sorry I have no idea. Have you tried converting to RAW also?

    @motteo: I guess the header is damaged somehow. Have you tried converting to RAW instead?

  6. Hi John,
    Really appreciate this post, it's the only one I can find that makes sense to me (I'm not really a so savvy with terminal...
    I too am having exactly the same problem as @Matteo
    DeanAladay$ /Users/DeanAladay/Desktop/mlv/mlv_dump -o outputfilename.RAW -r M26-1643.MLV

    MLV Dumper v1.0

    [i] Mode of operation:
    - Input MLV file: 'M26-1643.MLV'
    - Convert to legacy RAW
    - Output into 'outputfilename.RAW'
    [i] File M26-1643.MLV opened
    [i] File M26-1643.IDX opened (XREF)
    [i] XREF table contains 833 entries
    [i] Processing...
    [E] Missing file header
    [i] Processed 0 video frames

    Please, please help as I'm in desperate need to convert this footage asap! What can I do?

  7. Hey John,

    I actually have a gui based batch converter for OSX over on the ML forums that will process both into RAW and DNG. The thread can be found at:

    I'm still updating it to make it more robust based on the communities comments, so expect it to grow even more in the months to come!