Ultralytics YOLO

🌟 Summary (single-line synopsis) v8.3.251 improves training/integration reliability by initializing Trainer callbacks earlier (so Ultralytics HUB/Platform sees the original data input like ul://...) while also polishing profiling accuracy, tuning stability, and device/dataset/docs support 🧩🚀 📊 Key Changes Earlier Trainer callback initialization (PR #23155, @glenn-jocher) 🧠 on_pretrain_routine_start now runs before dataset resolution (get_dataset()), keeping the original args.data intact (e.g., ul:// URIs). DDP/world-size detection is computed earlier to ensure integrations start at the right time. Platform/Ultralytics HUB training logging made safer for concurrent runs 🧵 Platform callback state moved from global variables to per-trainer fields, reducing cross-talk when multiple trainings run in the same process. Training events now capture cleaner "trainArgs" and can attach a returned modelId for better event correlation. Better support for ul:// weights loading 🛰️ YOLO(...)._load() now recognizes ul:// as a valid remote source prefix (alongside http(s)://, rtsp://, etc.). More accurate FLOPs/profiling and benchmark reporting 📏 model.info() now accepts an imgsz argument, and benchmarks use it so FLOPs reflect the actual input size (not always 640). Tuner stability improvements 🎛️ Tuner now passes save_dir into subprocess runs to ensure consistent output paths. Plotting warns and safely exits if there are no valid fitness values (instead of failing). Removed unreachable code in Ray Tune helper (run_ray_tune) 🧹 Edge-hardware compatibility tweak: improved Rockchip detection 📟 is_rockchip() now handles SoC strings with suffixes like rk3588-..., improving detection on more boards. Docs and dataset quality updates 📚 New NVIDIA DGX Spark guide for running YOLO11 (including TensorRT tips + benchmarks) 🖥️⚡ VOC docs add an embedded training video 🎥 Kaggle docs fix code-block formatting and clarity TT100K dataset YAML and conversion script improved (better structure, metadata, and more stable class mapping) 🎯 Purpose & Impact More reliable Ultralytics HUB/Platform tracking & reproducibility 🛰️ Integrations can now record the true dataset reference (like ul://user/datasets/name) before it's resolved/rewritten—improving traceability and "training_started" metadata accuracy. Fewer issues when running multiple trainings in one environment 🧵 Per-trainer logging state reduces interference between runs (important for notebooks, orchestration systems, or multi-experiment workflows). More trustworthy model profiling numbers 📊 FLOPs and benchmark tables better match real-world settings when you profile with non-default imgsz. Smoother tuning workflows 🔁 More consistent output directories across subprocess tuning + fewer plotting failures when trials don't produce valid results. Better out-of-the-box experience on specific platforms 🧩 Improved Rockchip detection and new DGX Spark guidance help users deploy YOLO11 more confidently on edge devices and compact workstations. What's Changed SimpleNameSpace task arg fix by @glenn-jocher in https://github.com/ultralytics/ultralytics/pull/23148 Fix code blocks by @glenn-jocher in https://github.com/ultralytics/ultralytics/pull/23149 Remove dead code in run_ray_tune by @raimbekovm in https://github.com/ultralytics/ultralytics/pull/23147 Improve is_rockchip function to handle more device variants by @lakshanthad in https://github.com/ultralytics/ultralytics/pull/23153 Respect imgsz in ProfileModels FLOPs calculation by @artest08 in https://github.com/ultralytics/ultralytics/pull/23151 Add https://youtu.be/yrHzL8RyY6g to docs by @RizwanMunawar in https://github.com/ultralytics/ultralytics/pull/23154 docs: 📝 Add NVIDIA DGX Spark guide to documentation by @onuralpszr in https://github.com/ultralytics/ultralytics/pull/23144 ultralytics 8.3.251 Earlier trainer callback init by @glenn-jocher in https://github.com/ultralytics/ultralytics/pull/23155 New Contributors @artest08 made their first contribution in https://github.com/ultralytics/ultralytics/pull/23151 Full Changelog: https://github.com/ultralytics/ultralytics/compare/v8.3.250...v8.3.251