MKV is a common video file defined by Matroska Media, a new multimedia package format. The feature of MKV is that it could hold many types of encoded video, audio and subtitles stream.

To convert avi to mkv file, you may first install the proper avi decoder in your system. The video and audio stream in the avi container can be encoded by any codecs. So you have to try different decoders until you can preview the avi in Windows Media Player or MKV Converter. 

Download MKV Converter which can convert avi to mkv file. Then please install MKV codecs. Select an avi file, set some parameters such as DivX or XviD as the video compressor,  Microsoft ADPCM as the audio compressor, adjust the resolution, frame rate etc if necessary.

HDTV means High Definition Television which provides broader screen and higher definition than VCD or even DVD. HDTV technology having the best audio and video is the highest standard of DTV (Digital Television). The resolution of HDTV could reach as high as 1920 Ž× 1080 while the frame rate could reach to 60 fps. Besides, it adopts digital technology thus signalÃÔ anti-noise ability enhances greatly.

Please install HDX4 HDTV or FFDSHOW or other codecs for HDTV to mkv.

DVB stands for Digital Video Broadcasting. ItÃÔ a series of international recognized open standards for digital TV maintained by DVB Project, an industrial organization formed by over 300 members and launched by Joint Technical Committee formed by European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU). DVB transmission system makes use of all common television broadcasting transmission media including satellite, cable, terrestrial, SMATV, MNDSD, whose DVD Standards are respectively are DVB-S, DVB-C, DVB-T, DVB-SMATV, DVB-MS and DVB-MC.