FAQ - Frequently Asked Questions - Knowledge Base

Technical Terms

DivX is a ground-breaking video codec developed from the new MPEG-4 compression standard. A video codec is basically an add-on to your system that allows you to compress/decompress videos into the specified format. The DivX codec will allow you to play movies using any DivX-enabled player, including Windows Media Player. With the revolutionary compression technology incorporated into DivX, DivX movies not only offer better compression and higher quality videos than regular MPEG movies, they also require less time to encode. DivX codec can compress/encode near DVD-quality movies onto a 700MB CD. Combined with MP3 audio, DivX videos offer both high quality video and sound.

XviD is similar to DivX in that it is also based on the new MPEG-4 compression standard. XviD is a type of new open-source video codec that is currently being developed around the world. Like DivX, installing Xvid codec will allow you to play XviD movies on Windows Media Player or any XviD-enabled player.

MPEG (Motion Picture Experts Group) is the developer of MPEG-1 (VideoCDs), MPEG-2 (DVD and SuperVCDs), and MPEG-4 (ASF, DivX, WMV) video compression standards. The MPEG group is also responsible for the development MP3 and AAC audio compression standards.

VOB stands for Video OBjects, which is the format in which DVD movies are stored. Within each of these VOB files is stored a number of video/audio/subpicture streams. SUBPICTURE: Subpicture streams refer to the subtitles on DVDs and other VOB files. These subtitles are not text files, but rather, video streams that overlay on top of the main picture stream. These subpicture streams can be turned on or off.

AVI (Audio Video Interleave) is a file format that can contain video/audio compressed standards using different combinations of codecs (eg. DivX + WMA or Indeo + PCM). As long as the codec is available for encoding/decoding, AVI can contain the many different combinations of video and audio.

AC3 (Audio Coding 3) is synonymous with Dolby Digital, which is an advanced audio compression technology that allows encoding of six separate channels at the bitrate of 448kbit/s.

DTS digital sound provides the technology for virtually all soundtracks. Though the technology used by DTS differs from those used in Hollywood motion pictures, their outstanding techniques allow users to enjoy sound closely matching the original.

WMA (Windows Media Audio) is a format developed by Microsoft for audio streaming and compression.

Ogg Vorbis
Ogg Vorbis is a new audio compression format similar to other digital audio formats like MP3, VQF, and AAC; however, it is completely free and unpatented.

ID3 Tag
ID3 is the tag embedded in MP3s that tells your MP3 file what song, artists, and album it comes from. These tags can be edited.

480 progressive is a form of standard-definition digital television (SDTV) similar to VGA computer displays, but not considered high-definition television (HDTV). A DVD's resolution is 480p, but this resolution can only be seen if the DVD player outputs a progressive-scan signal, along with that the DTV has progressive-scan or component-video inputs.

480 interlaced is a form of standard-definition digital television (SDTV) that approximates the quality of analog television. Although a DVD's resolution is 480p, it is often viewed at 480i on an NTSC analog television.

720 progressive is one of two used formats designated as high-definition digital television (HDTV) in the ATSC DTV standard. This technology uses progressive scanning and comprises of 720 vertical pixels and 1280 horizontal pixels.

1080 interlaced is one of two used formats designated as high-definition digital television (HDTV) in the ATSC DTV standard. This technology uses interlaced scanning and comprises of 1080 vertical pixels and 1920 horizontal pixels.

NTSC (National Television Standards Committee) is the developer of a set of standard protocols for TV broadcast transmission and reception in the United States. The two other standards are PAL and SECAM, which are used in other parts of the world. An NTSC image has 525 horizontal lines per frame, and these lines are interlaced scanned from left to right and top to bottom. NTSC signals are not directly compatible with computer systems.

PAL (Phase Alternation Line) is the analog TV display standard used mainly in Europe. The PAL image has 625 horizontal lines per a frame, rather than the 525 lines used by NTSC. The color definitions between the standards differ slightly.