FLV

Flash Video is a container file format used to deliver digital video content (e.g., TV shows, movies, etc.) over the Internet using Adobe Flash Player version 6 and newer. Flash Video content may also be embedded within SWF files. There are two different video file formats known as Flash Video: FLV and F4V. The F4V file format is based on the ISO base media file format and is starting with Flash Player 9 update 3.[1][2] Both formats are supported in Adobe Flash Player and developed by Adobe Systems.

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MKV

Matroska file extensions are .MKV for video .The Matroska Multimedia Container is an open standard, free container format, a file format that can hold an unlimited number of video, audio, picture, or subtitle tracks in one file.[1] It is a universal format for storing common multimedia content, like movies or TV shows.Matroska is similar in concept to other containers like AVI, MP4, or Advanced Systems Format (ASF), but is entirely open in specification, with implementations consisting mostly of open source software.

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Step-By-Step to Convert FLV to MKV

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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