Guide to Defining Video Quality Requirements
![Section 1 of 11 of step 3 -- Understand System Tasks and System Functions -- in the bar chart highlighing the 4-step process for definfing video quality requirements.](https://webarchive.library.unt.edu/web/20130215182603im_/http://www.pscr.gov/outreach/vqips/vqips_guide/images/03_sys_tasks.png)
Video System Tasks
Three fundamental tasks provide the foundation for any basic video system. Each task includes functions requiring equipment that has a direct effect on the quality of the video, which means each piece of equipment has the potential to alter the video to a degree that impacts the video’s usability.
![Full video system illustrating three core functions: acquisition, transmission, and display.](https://webarchive.library.unt.edu/web/20130215182603im_/http://www.pscr.gov/outreach/vqips/vqips_guide/images/full_system.png)
The Acquire, Deliver, and View tasks each include functions. Click a task or function in the figure for information.
The figure provides a reference model for core system functions, which support three primary tasks:
Acquire Video — Includes focus and capture functions, and may include a built-in CODEC, which can perform the processing function’s encoding/decoding operations. However, in some video systems, such as those used for surveillance applications, the encode operation might be performed in a separate IT space.
Deliver Video — Includes the processing, storage, and transport functions. Sometimes the acquire and view tasks include the processing function’s encoding/decoding operations.
View Video —Includes the display function and may include a built-in CODEC, which can perform the processing function’s decoding operation. However, in some video systems, such as those used for surveillance applications, the decode operation might be performed in a separate IT space.
The exact demarcation for each of the three tasks can vary from application to application due to integration of various functions within your equipment.