Digital Video

Digital Video

1. Meaning

   • The video is a technology used to capture, recording, processing, transmitting and reproducing a sequence of images representative of a scene that is in motion. The term, which comes from the Latin "see", is currently associated with different storage formats, whether analog (VHS and Betamax) and digital (MPEG-4, DVD, Quicktime, etc.).

2. Type of video

   • Analog
     • Analog technology records waveforms as they are
   • Digital
     • Samples analog waveforms into a limited set of numbers and records them.

3. Formats

   • AVI (.avi): Most commonly contains M-JPEG,or DivX, but can contain nearly any format
   • Quicktime: Most often used for the locked Apple Sorenson codec, or for Cinepak (free), but can also hold other codecs such as mjpeg, etc.
   • WMV (.wmv): More or less MPEG4; can contain nearly any codec, including several Microsoft spinoffs of MPEG-4
   • ASF ("Advanced Streaming Format", .asf): a subset of wmv, intended primarily for streaming

4. Synthesis

   • Visual multimedia source that combines a sequence of images to form a moving picture. The video transmits a signal to a screen and processes the order in which the screen captures should be shown. Videos usually have audio components that correspond with the pictures being shown on the screen.