Guide to Defining Video Quality Requirements
Revised May 29, 2012
![Section 2 of 9 of step 2 -- Generalize Use Cases into Use Classes -- in the bar chart highlighing the 4-step process for definfing video quality requirements.](https://webarchive.library.unt.edu/web/20130215140233im_/http://www.pscr.gov/outreach/vqips/vqips_guide/images/02_use_classes.png)
Generalized Use Class Aspects
![Generalized use class aspects.](https://webarchive.library.unt.edu/web/20130215140233im_/http://www.pscr.gov/outreach/vqips/vqips_guide/images/use_class_aspects337x233.png)
For each use case, determine the specific value for each aspect. The combination of common values across use cases will form your generalized use classes.
A use class shares certain important aspects of specific use cases that are common to other use cases, allowing you to make generalizations between them. All use cases have an analyst and a scene under observation. For each of your use cases, apply the Generalized Use Class Questionnaire to derive generalized aspects from the analyst’s intended use of the video (Use Characteristics) and what is in the scene under observation (Scene Content).
Each of the following generalized use class aspects can impact the quality of the video content as seen and used by the analyst. Click any of the following generalized use class aspects or those in the figure for aspect information.
Use Characteristics
Scene Content