# Summary of S4-251880: Work Plan for Beyond 2D Video Phase 2 Study

## Document Overview

This contribution proposes a work plan for the Study Item "Beyond 2D Video Phase 2" (FS_Beyond2D_Ph2), which focuses on dynamic mesh technologies for mobile applications. The document has been revised from an earlier version (S4-260139) with updated timelines and refined objectives.

## Study Item Objectives

The study encompasses five main technical areas:

### 1. Dynamic Mesh Content Generation for Prosumer Use Cases
- Focus on offline production scenarios (e.g., social media services)
- Limited camera setup (less than 5 cameras)
- Offline production and compression workflows

### 2. Dynamic Mesh for Real-Time Services
- Live applications (e.g., concerts, sports training on social media)
- Real-time compression requirements
- **Note:** Avatar-mesh-based real-time communication is explicitly out of scope

### 3. Evaluation of Dynamic Mesh Formats
- Assessment of existing and emerging compression technologies (e.g., MPEG V-DMC with HEVC as underlying 2D codec)
- Objective and subjective testing methodology similar to TR 26.956 approach for V-PCC
- Use V-PCC as baseline for comparison
- Reuse of existing performance results from MPEG or other SDOs where applicable
- Option for independent 3GPP evaluation if suitable results unavailable

### 4. Implementation Aspects Study
- Number of required video decoders
- Pixel rate limitations

### 5. Comparative Analysis and AI Quality Assessment
- Compare dynamic mesh with other formats
- Derive recommendations for format selection under different conditions
- **New:** Develop framework for assessing quality of AI-generated dynamic meshes without requiring reference or original model

## Proposed Timeline

### SA4#134 (November 2025, Dallas)
- **Target:** Agreement/Endorsement of Study Item
- **Completion:** 0%

### SA#110 (December 2025, Baltimore)
- **Target:** Approval of Study Item
- **Completion:** 0%

### SA4#135 (February 2026, India)
- **Activities:** Initiate work on Objectives 1a-c, 2, and 3a-b
- **Priority documents:** Time Plan, TR Skeleton and Scope, Draft Use Cases/Scenarios
- **Target Completion:** 20%

### SA4#135-bis-e (April 2026)
- **Activities:** 
  - Progress work on Objectives 1a-c, 2, 3a-b
  - Initial work on Objective 1d (evaluation) and 3c-d (implementation aspects and comparison)
- **Target Completion:** 45%

### SA4#136 (May 2026, Montreal)
- **Activities:**
  - Progress Objectives 1d and 3c-d
  - Initiate potential normative work and conclusions
  - Communication with other 3GPP WGs and external organizations
  - Identify remaining open issues
  - Agree on TR 26.xxx for SA information
- **Target Completion:** 75%

### SA#112 (June 2026, Singapore)
- **Activities:** Present TR 26.xxx to SA for information
- **Target Completion:** 75%

### SA4#137-e (August 2026, online)
- **Activities:**
  - Complete Objectives 1d and 3c-d
  - Complete identification of potential normative work
  - Complete all remaining open issues
  - Agree on TR 26.xxx for SA approval
  - Present TR 26.xxx to SA for information
- **Target Completion:** 100%

### SA4#138 (November 2026, Calgary)
- **Activities:**
  - Complete evaluation work
  - Complete implementation aspects study
  - Complete comparative analysis
  - Finalize conclusions and normative work identification
  - Agree on TR 26.xxx for SA approval

### SA#114 (December 2026, Boston)
- **Activities:** Send TR 26.xxx to SA for Approval

## Key Changes from Previous Version

- Timeline extended and adjusted (meetings shifted from 2025-2026 to 2025-2026 with different completion targets)
- Refined objective descriptions with clearer sub-categorization (Objectives 1a-d, 2, 3a-d)
- Added explicit framework development for AI-generated dynamic mesh quality assessment
- Clarified priority document types for initial meetings
- Updated meeting locations and dates