How to edit MTS, M2TS, TS files on Mac os x?
Tutorial: 
This article will intro some wonderful video editor software and help you import MTS camcorder video to these tools on Mac.
iMovie(freeware) is a video editing software application, with it the Mac user can edit the video clips, add titles, add music, apply Effects (basic color correction and video enhancement tools) and transitions such as fade-in, fade-out, and slides etc on Mac.
Final Cut Express/Pro supports edit video like: key frame filter, dynamic RT, which changes real-time settings on-the-fly, motion path keyframing, opacity keyframing, ripple, roll, slip, slide and blade edit, picture-in-picture and split-screen effects etc on Mac.
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Download mts converter for mac trial version
Adobe Premiere Pro supports high resolution video editing at up to 10,240 x 8,192 resolution, at up to 32-bits per channel color, in both RGB and YUV. Audio sample-level editing, VST audio plug-in support, and 5.1 surround sound mixing are available.When used with Cineform's Neo line of plug-ins, it supports 3D editing with the ability to view 3D material using 2D monitors, while making individual left and right eye adjustments.
Tips: MTS video from Canon, Sony, Panasonic, JVC etc camcorder can not be natively accepted by these editor software, we need to convert MTS files to MOV, DV, MP4 etc, then imported converted MTS movie to iMovie, FCE, FCP, Premiere Pro for editing on Mac.
MTS converter for Mac supports convert and import MTS video to iMovie, FCE, FCP, Premiere Pro MOV, DV, MP4 etc on Mac and also supports edit MTS easily.
MTS video editor for Mac supports edit AVCHD, MTS, M2TS, TS, TRP, TP files, like: Clip(set start and end), Crop(set aspect ratio 16:9/4:3), Merge(join several files into one), Apply effect(adjust brightness, contrast, and saturation etc), set output parameter(adjust resolution, Frame Rate, Encoder and Bitrate ), Snapshot, Rotate etc.
Step by step to edit MTS video on Mac
Step 1: Download and install "MTS editor for Mac"
Download the software, install and run a test. Please don't hesitate to contact us if there is any problem during the process. 
Step 2: Load file
Click Add MTS File on the left top of the panel to import MTS file to edit, batch import supports.
Step 3: Crop video
Click "Edit" on the left of the panel, choose "Crop"
Setting aspect ratio:set the output aspect ratio from Zoom drop-down, there are four options: Original, Full Screen, 16:9 and 4:3 at your selection.
Setting the values: You can type the value directly or set the value in Left, Right, Top and Bottom area to set the position of the cropping frame. 
Choose"Effect", you can apply effect for the MTS movie, just try.
Step 4: Clip video
Click "Clip" on the left of the panel to pop up a Clip window, where you can cut the original file to a certain length, this can be realized by dragging the first slider to set the start time and the second slider to set the end time. 
Step 6: Video settings
Click "Settings" on the bottom of the panel to pop up a Settings window where you can tweak Resolution, Encoder, Frame Rate and Bitrate of the original file. 
After all the required settings have been done, click "Convert" to start converting automatically, wait for a while, you will get what you want.
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