WTV (Windows Recorded TV Show File) is a video format recorded using Windows Media Center (WMC). WMC is a program for recording TV shows and playing multimedia content. WTV uses the MPEG-2 compression standard for videos and Dolby Digital AC-3 or MPEG-1 Layer II for audio. Some WTV files might include metadata as well as DRM protection.
DRD Systems VideoReDo Bigasoft WTV Converter CyberLink PowerDVD 17 Microsoft Windows Media Center
FLV (Flash Video) is a video container format developed by Adobe Systems and comes with a .flv filename format. FLV is primarily used to stream audio, video, and text data such as subtitles. It supports MPEG-4 Part 10 (H.264) video codec and AAC sound.
RealPlayer, Apple QuicTime Player
VLC Media Player