Converting Sony AVCHD .mts to useable format for HitFilm

I recently bought a Sony FDR-AX100 and it records an .mts file.  I've searched this forum and tried a few different conversion programs.  VirtualDub was suggested but when I tried to open the file it wouldn't allow me to select an mts file.  I then tried ClipToolz and converted it to the suggested DNxHD which took the file from 441mb to almost 4gb.  When I import it into HitFilm, nothing appears in the thumbnail or in the trimmer.  

When I first played with HitFilm Express yesterday and used the demo files provided for Portal Combat which were mp4s, they played fine and I could scrub in the trimmer without any issues.  I've converted some of my clips to mp4 and they stutter when I try to scrub through.  I've converted my clips to the Portal Combat mp4 clip that doesn't stutter (using properties) and they supposedly match - both 24 bit color, AVC / H.264 codec.  

Can someone please give me some suggestions on how to convert these mts files to a format that I can scrub through in HitFilm without stuttering and still have good quality?  Thanks!


  • NormanPCN
    NormanPCN Posts: 4,211 Enthusiast

    When you converted to DNxHD, what container did you output to. MOV or MXF. MXF will not work. It has to be MOV and of course you will need Quicktime installed to read those MOV files in Hitfilm.

    The Portal combat example project videos are 720p24 AVC which is easier to edit than 1080 would be. They are also not using CABAC encoding which improves decode performance as well.

    To get regular AVC to edit as best as it can you probably would want to use Baseline profile. This restricts the encode to 1 reference frame, no b-frames and no CABAC. All I-frame (Intra) would be even better if the transcoder you use can generate it. You did not mention what transcoder you used to generate the AVC MP4 files.

  • SteveKarstensen
    SteveKarstensen Posts: 335 Just Starting Out*

    FWIW, I have the best luck using the .m2ts format for my imported files.  I convert everything via Video2Video before using it in Hitfilm.

  • BobDiMarzio
    BobDiMarzio Posts: 630 Just Starting Out

    In Hitfilm 3pro or 4 pro etc, the AVCHD MTS file is directly editable.  In express the Dolby encoding is not supported.     I checked, you can transcode using Handbrake without a measurable increase in file size. 

  • WillBellJr
    WillBellJr Posts: 30 Enthusiast
    edited November 2015

    I've come to swear by TmpgEnc Tools

    Especially their MPEG Smart Renderer and Video Mastering Works 5.

    The smart renderer only has to render the modifications made to my MP4 files (cuts, transitions, titling etc.,) the rest is copied though to the output file untouched.

    Rendering that used to take me hours with other tools now only takes me minutes - great stuff!



  • Thank you everyone.  After going back and playing with it again, I'm not seeing a lot of stuttering between the original mts file and the mp4.  So I'm guessing it's mainly due to the size difference.  I didn't realize the portal combat video was 720p and mine are 1080p.  

    Also, Norman, you said " They are also not using CABAC encoding which improves decode performance as well."  I have no idea what this means but am very interested if this is something I can do to my files to get them to perform better?  Thanks!

  • NormanPCN
    NormanPCN Posts: 4,211 Enthusiast

    CABAC is simply an encoding option available in AVC/H.264. It provides for smaller files but it is slower to decode. I mentioned this since you mentioned you had tried some "mp4" conversions of source source clips. mp4 is not specific, it is just a file format, and I assumed your mp4 files were probably using the AVC video codec.

    Not all AVC encoders give you direct control over the CABAC option, but most will let you select Baseline profile, so I mentioned that in my previous post, as one way to get better decode performance from AVC.

    None of this means anything unless you are converting your source files to a new AVC format. Your AX100 source files are already in AVC format. Just in a slightly more difficult to decode variant (aka slower).