Task-Based Video Quality Update

1. Task-Based Video Quality Update Or, what has Carolyn been up to this past year?VQEG, June 2009

2. Last You Heard • Background • Video quality research for task-based video • Initial application: public safety agencies • Measurement: P.912 approved • “Video Quality Assessment Methods for Recognition Tasks” • No scales!!

3. Since Then • Video Quality in Public Safety (VQiPS) Conference convened 2/09. • Outcomes • Working Group under Dpt of Homeland Security • Active projects: • Use cases • Glossary • Standards inventory • Scene pool creation

4. Use Case Project • Old way of thinking: • Every application its own use case • E.g. police in-car cameras, fire, EMS, SWAT • New way: • Each case boils down to “visual intelligibility” of an intended target • Extract common scene parameters that affect the ability to recognize a target • Determine set of discrete values for each parameter • Design use cases based on permutations of parameters

5. Use Case Parameters

6. Parameter Definitions • Use Paradigm • Use Timeframe – is the video used for real-time applications or recorded for later use? • Li – Live, or real-time. • Re – Recorded. • Discrimination Level – what is the end user’s ultimate goal? • EA - General Elements of the Action (e.g. people present, high-level description of actions that took place). • TCl - Target Class Recognition (e.g. car vs. van). • TCh - Target Characteristics (e.g. gender, markings, smaller actions). • ID - Target Positive ID (e.g. face, object, alpha-numeric). • Scene Content • Target Size – how much of the frame does the object or person of interest occupy? • Lg – Large, the target occupies a large percentage of the frame. • Sm – Small, the target occupies a smaller percentage of the frame. • Scene Complexity – how much motion (either target or camera) and how much spatial detail is in the video frame? • Hi – High complexity, there is a lot of motion or edges in the video. • Lo – Low complexity, there is not much motion, or many edges. • Lighting Level – is the lighting generally uniform, or are is there near-black to daylight ranges in the video frame? • CstH – Constant lighting, at a comparatively bright level. • CstL – Constant lighting, at a comparatively dim level. • Var – Variable, the range of light in the scene varies from bright to dim, either within one frame, or over time.

7. Obvious Questions • What is “small” or “large” • What is “complex” • What is a high dynamic range for lighting • Etc

8. Glossary Project • Merge existing documents from • Forensic video community • Security video community • others

9. Standards Inventory Project • Actually a matrix • Type of standard • Specifications (actual numbers) • Algorithms • Test methods (Evaluation) • Operating Procedures • Definitions and Units • Models • Component of video system it applies to

10. Scene • Content 6. Storage 5. Transport 2. Optics 3. Capture 4. Processing 7. Display Figure 1: The Video System Video System Components

11. Standards Inventory

12. Future • Performance Specification recommendations • Subjective testing based on use cases • Models • Bitstream?