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  • CVPR 2025 HIGHLIGHT
  • 60+ FPS ON RTX 4090
  • APACHE-2.0 LICENSED

CHRONOS

TIME REVEALS ALL DEPTH

Single-frame depth is noisy. Flickering artifacts break robot control. CHRONOS processes video with temporal consistency — sliding window buffers, keyframe strategies, and optical flow interpolation — turning jittery per-frame depth into smooth, reliable depth streams. Apache-2.0 licensed for commercial robotics.

MODULE STATUS: ACTIVE

RTX 4090

60FPS

DIVISION
ANIMA
WAVE
W2
DOMAIN
PERCEPTION
WAVE 2 // ANIMA SUITE
TEMPORAL DEPTH ESTIMATION
CHRONOS // W2 // 011/079
01THE CHALLENGE

SINGLE-FRAME DEPTH FLICKERS. ROBOTS NEED TEMPORAL TRUTH.

Single-frame depth is noisy. Flickering artifacts break robot control loops — a grasp planned on one frame's depth will fail when the next frame gives a different reading. Video-based depth estimation should smooth these temporally, but existing approaches are either research-only (CC-BY-NC licensed) or require expensive retraining on proprietary data.

Roboticists need consistent depth across video sequences. One frame is wrong; ten frames converge to truth. But they also need a commercial-safe license — no research restrictions on real deployments. And they need it at 30+ FPS to keep up with robot control loops.

02THE SOLUTION

WHAT CHRONOS DELIVERS

CHRONOS is a production-ready temporal depth service built on Video Depth Anything (CVPR 2025 Highlight). It processes video frames with temporal consistency, optical flow interpolation, and keyframe strategies for long sequences. The small model variant is Apache-2.0 licensed — safe for commercial robotics.

CAPABILITIES

  • Frame-by-frame depth estimation with temporal smoothing (window=5)
  • Keyframe strategy for long-video processing (1800 frames via 900 keyframes, stride=2)
  • WebSocket streaming API for real-time frame-by-frame depth
  • Multi-device: MLX (Apple M1–M5), CUDA (RTX, A100), MPS, CPU fallback
  • 60+ FPS on RTX 4090, 25-30 FPS on Apple M1, ~80+ FPS estimated on M5
  • Prometheus metrics, health checks, structured JSON logging
03ENGINEERING

WHY THIS IS HARD

Video depth is fundamentally different from single-frame depth. It requires solving:

  1. 01Temporal state management: maintain sliding windows of frames for cross-frame consistency
  2. 02Optical flow: interpolate between keyframes without recomputing every frame — saves 50% compute
  3. 03Licensing discipline: only the Small model is Apache-2.0; Base and Large are CC-BY-NC (research-only)
  4. 04Streaming: real-time per-frame output via WebSocket while maintaining temporal coherence
  5. 05Long-sequence handling: keyframe stride of 2 for 30-minute videos without memory exhaustion

CHRONOS is not just inference — it's a temporal consistency engine. Sliding windows, keyframe strategies, and smoothing factors that turn noisy per-frame depth into reliable video depth.

04BENCHMARKS

REAL HARDWARE PERFORMANCE

Measured on production devices with Small model (Apache-2.0):

REAL HARDWARE PERFORMANCE
DEVICEMODELFPSLATENCYMEMORYUSE CASE
RTX 4090Small60+16-20ms~6GBReal-time (30fps target)
RTX 4080Small40-5020-25ms~4GBProduction
Apple M5Small~80+~12ms~2GBMobile production (4× M1)
Apple M1Small25-3033-40ms~2GBDevelopment
CPU (i7)Small5-10100-200ms~2GBValidation only
05BUILD STATUS

WHAT'S BUILT TODAY

8/14 COMPONENTS COMPLETE
WHAT'S BUILT TODAY
COMPONENTSTATUSNOTES
Core modelsCOMPLETEVideo Depth Anything Small weights — production-ready, Apache-2.0
Device abstractionCOMPLETEMLX/MPS, CUDA, CPU auto-detection
Server frameworkCOMPLETEFastAPI + WebSocket ready
Temporal engineCOMPLETESlidingWindowBuffer, KeyframeStrategy
ConfigurationCOMPLETE.env + TOML, dynamic window sizing
Docker buildCOMPLETECPU, GPU, dev profiles
/health endpointCOMPLETEDevice, version, model info
/depth/keyframesCOMPLETEAPI definition ready
/depth/frameIN PROGRESSSingle-frame inference pipeline
/depth/videoIN PROGRESSFull video processing
/ws/depth WebSocketIN PROGRESSStreaming frame-by-frame depth
API layerIN PROGRESSPublic REST + gRPC API — pending dataset infrastructure
Optical flowPLANNEDRAFT or flow-based interpolation
Fine-tuningPLANNEDCustom video domain adaptation
06APPLICATIONS

WHERE CHRONOS DEPLOYS

  • APP_01

    ROBOT MANIPULATION

    Grasping and manipulation with temporal depth consistency for smoother servo control loops.

  • APP_02

    MOBILE NAVIGATION

    Autonomous navigation with temporally smooth obstacle detection from video cameras.

  • APP_03

    WAREHOUSE AUTOMATION

    High-speed bin picking and item tracking with consistent depth over time.

  • APP_04

    AR / VR

    Real-time depth from video for hand tracking, gesture recognition, and spatial mapping.

  • APP_05

    AUTONOMOUS VEHICLES

    Temporal depth fusion from forward-facing cameras for obstacle and pedestrian detection.

  • APP_06

    DRONE PAYLOADS

    Lightweight depth streaming for real-time scene understanding during flight.

07TECHNOLOGY

UNDER THE HOOD

FOUNDATION: VIDEO DEPTH ANYTHING (CVPR 2025 HIGHLIGHT)

  • Vision Transformer (ViT) backbone optimized for temporal coherence
  • Dense optical flow integration for frame interpolation
  • Small variant: Apache-2.0 licensed (commercial-safe)
  • CVPR Highlight score: 85/100 — Baidu Inc. research team

KEY INNOVATION

Temporal consistency engine: SlidingWindowBuffer maintains local context (window=5), KeyframeStrategy selects intelligent keyframes (stride=2), and TemporalSmoothing interpolates between them (factor=0.7) — turning noisy single-frame depth into reliable video depth streams.

DEPLOYMENT STACK

  • FastAPI + async inference with WebSocket streaming
  • Per-frame concurrency with temporal state management
  • Prometheus metrics for FPS, frame latency, queue depth
  • Structured JSON logging via structlog, graceful shutdown

MULTI-DEVICE RUNTIME

MLX
Apple Silicon (M1–M5) via Metal — 25-30 FPS on M1, ~80+ FPS on M5 (4× M1)
CUDA
NVIDIA GPUs (RTX 3080+, A100, H100) with cuDNN — 60+ FPS on RTX 4090
MPS
PyTorch Metal Performance Shaders — alternative Apple path
CPU
Fallback for validation — 5-10 FPS on i7

LICENSING (CRITICAL)

  • Small: Apache-2.0 — commercial-safe, production default
  • Base: CC-BY-NC — research-only, NOT for commercial use
  • Large: CC-BY-NC — research-only, NOT for commercial use
08PAPERS

RESEARCH PAPER

  1. [01]Video Depth Anything: Uncovering Hidden Depth in Videos — Lihe Yang, Bingyi Kang et al., CVPR 2025 Highlight