M4V

The M4V file format is a video container format developed by Apple and is very similar to the MP4 format. The primary difference is that M4V files may optionally be protected by DRM copy protection. Apple uses M4V to encode video files in its iTunes Store. Unauthorized reproduction of M4V files may be prevented using Apple's FairPlay copy protection. A FairPlay-protected M4V file can only be played on a computer authorized (using iTunes) with the account that was used to purchase the video. [1] In QuickTime, M4V videos using FairPlay DRM are identified as "AVC0 Media".

- - Wikimedia

FLV

A filename extension is an identifier specified as a suffix to the name of a computer file. The extension indicates a characteristic of the file contents or its intended use. A file extension is typically delimited from the filename with a full stop (period), but in some systems it is separated with spaces. Some file systems implement filename extensions as a feature of the file system itself and may limit the length and format of the extension, while others treat filename extensions as part of the filename without special distinction.

- - Wikimedia

Step-By-Step to Convert M4V to FLV for Mac

Interface

Step 1. Download and install the program, then double click it to run it, and then you'll see the main interface of the program.

Load Files

Step 2. Click "Add File(s)" button. Here you can select "Add Video" or "Add Folder" button to add files as you like.

Profile

Step 3. Click the drop-down arrow right beside the "Profile" column and select your desired video format from the drop-down list.

Edit

Step 4. Click "Edit" button to customize the output video like Effect, Trim, Crop, 3D Settings and Watermark.

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