Screencast

from Wikipedia, the free encyclopedia

A screencast ( Engl. ) Is a video recording, the processes involved in the use of software on the computer reproduces screen and possibly describe. Often the processes are accompanied by audio comments. Just as a screenshot represents a single image of the screen, the screencast is a sequence of such images.

A distinction is made between screencasts in the narrower sense, i. H. Videos that are available on the Internet over a long period of time and can be accessed as often as required, and those screen recordings that are transmitted in real time - these are more commonly grouped under the term desktop sharing . The technical difference is small.

history

Software for recording screen activity in the form of video has been around since at least 1993. One example is Lotus CamStudio. Well-known manufacturers named (and name) the works created from the respective software very differently, such as screen recording , screen capture or viewlet .

In the course of time, however, the "screen videos" became more and more professional, so it was worthwhile to put them in a separate category. Because with simply gluing together pictures, as you would e.g. B. from GIF animations, screencasts can no longer be compared. Precisely because these are so short, attention is paid to every detail; the viewer's attention is often drawn to the essential image components through spotlighting .

Recently, the terms screen capture or video capture have also been used in another area. Because with increasing hardware performance and improved programs, it is possible to create so-called analog private copies and thus circumvent copyrights. The legal situation is unclear.

Origin of the term

The term screencast was coined by the columnist and computer book author Jon Udell , after he had called on his blog in mid-November 2004 to suggest terms for this form of video. Inspired by the success of the term podcast , which summarized a new multi-step technical process in one catchy word and quickly spread throughout the world, Udell saw the time had come to coined an umbrella term.

The term is linguistically derived from the English components screen (picture or screen) and cast (from broadcasting = radio / broadcasting).

Forms of application

Wikipedia tutorial (no sound)

There is a multitude of content that can be transported via screencasts - but the concept is always the same:

  • teach the use of software
  • Document installation processes
  • represent new features of the software
  • Documentation of bugs to support the developer in troubleshooting
  • Screencasts are used in marketing to present new products.

Screencasts are usually only short videos, rarely longer than 5 to 10 minutes. They show e.g. B. targeted small parts of a product or software and can also be used as an advertising measure.

Technical aspects

In order to record a screencast, a screen camera (or screen camera ) is required . This is mostly software that creates a digital video as a sequence of individual images on a computer screen. A “video camera” therefore has no optical components, as the image information is read directly from the video memory.

In contrast to streaming videos, the user can pause the generated videos at any time or watch them as often as required in order to understand individual content.

generation

The creation of a screen video usually follows the following scheme:

  • First, a portion of the screen or the entire screen is marked as an area to be recorded.
  • The refresh rate , video compression and audio data compression of the screen video should be specified. As a rule, one tries to achieve the smallest possible video with good image quality, especially when publishing the video on the Internet . The audio data stream can be z. As with the MP3 - Codec compress. The video data stream could be z. B. compress with DivX . It is also possible to save as a Flash file.
  • Then the recording is started and a video data stream is created from a sequence of individual images. The individual images are created like a screenshot .
  • A microphone can also be used to record audio commentary on the screen video that explains what is happening on the screen. This may make the screen activity recorded in the video easier for viewers to understand.
  • After the recording is finished, the video can still be edited, e.g. B. by cutting and dubbing the video.
  • For different delivery formats such as CD ( Compact Disc ), DVD or via the Internet , the finished screen video can be compressed even more or converted into another video format .

Software to create

Open source representatives:

Proprietary representatives are:

Hardware to create

Proprietary representatives are:

  • VGA2USB (external hardware solution for USB from Epiphan Systems)

See also

Web links

Wiktionary: Screencast  - explanations of meanings, word origins, synonyms, translations
Commons : Screencast videos  - collection of pictures, videos and audio files

Individual evidence

  1. ↑ Copy DVD analog ( memento of the original from April 12, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. - technical options at www.3sat.de , January 26, 2006 @1@ 2Template: Webachiv / IABot / www.3sat.de
  2. ↑ Analogue copy of copy-protected CDs under the new copyright law: Permitted or not? - Discussion of the analogue private copy on www.internetrecht-rostock.de
  3. ↑ Jon Udell: Jon Udell: Name that genre . InfoWorld. November 15, 2004. Archived from the original on June 16, 2008. Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved June 12, 2008. @1@ 2Template: Webachiv / IABot / weblog.infoworld.com