Codecs for Videos

  • It is an electronic circuit or software that compresses or decompresses the digital videos.
  • The device that only compresses is typically called an encoder and one that only decompresses is a decoder.
  • The compression is typically lossy.
  • The compressed video lacks some information present in the original video.
  • A consequence of this is that decompressed video has lower quality than the original video, uncompressed video because there is insufficient information.


Commonly used video codecs:


H.264/MPEG-4 AVC:
  • This is the most common codec used in modern camcorders and digital cameras that capture the file based devices like hard drives, memory cards...etc.



MJPEG:
  • It is the most common video format.
  • It contains MPG, MPA, M15, MIV, MP2...etc.
  • It includes MPEG video, MPEG audio and MPEG (video, audio).
  • MPEG-3 is a audio file.
  • Video includes MPEG-1, MPEG-2, MPEG-4.
MPEG-1:
  • It is widely used in the production of VCD and download of some video clip.
  • The file format is generally .mpg and .dat files.


MPEG-2:
  • It is widely used in production of DVD and some of HDTV and high demand video editing.
  • The file format is generally .vob file.
MPEG-4:
  • It is used by many encoding formats, such as ASF, Divx, Xvid, MP4 are using MPEG-4.



Divx:
  • Video encoding technology can be said produced for DVD.
  • Which works with a certain type of MPEG-4 and often used to rip DVDs in pre-HD era.
  • Most of Divx videos use .avi file extension, .Divx and .Div extension.


Xvid:
  • It is an open source version of Divx, popular among movie pirates.
  • Its file extension is .avi.


Google codecs:
  • VP6, VP6-E, VP6-S, VP7, VP8, VP9 which are high definition video compression and codecs developed by On2 technology.
  • Which used platform such as Adobe flash player 8 and above, Adobe flash lite.
  • Supports resolution up to 720p and 1080p.
  • VP9 supports resolution upto 2160p.


Microsoft codecs:
  • WMV (Windows Media Video), it includes WMV7, WMV8, WMV9.


Applications:
  • Video codecs are used in DVD and VCD players and recorders, Video broadcast system, personal computer and variety of othe applications.


Examples:








My notes images: