Constriction of video

Constriction ( Graphics Media)
In computer field, constriction is a method of decreasing resolution of a video. The video quality is decreased to allow non authorized users to see video with less resolution, quality.
Details
Some videos have licenses and an owner of video may not want to all to see the video with same resolution, quality. He may allow non licensed users to see the video with lower quality and may ask to purchase the video to see it with full resolution. To decrease the quality of the video the frame of image to be shown if rendered in memory with smaller resolution. Again that memory is considered as a source frame and tried to render upon big rectangle to be displayed.
Implementation
Constriction can be implemented in the software and can be accelerated using a graphics card. A video may contains multiple streams(multi stream videos which run parallel to each other) which could be combined in a single frame and then shown finally...