Release Notes — Version 26.06#

July 2026#

Core Improvements

  • Harmonizer gRPC Naming: gRPC server flags are renamed from --enable-difix / --difix-* to --enable-harmonizer / --harmonizer-*. Legacy difix flags still work and redirect to their Harmonizer equivalents but emit deprecation warnings. See :doc:Use Harmonizer for Post-Processing <../nurec/harmonizer> and :doc:Use the NuRec gRPC API Server <../api/grpc_api_guide>.

  • Harmonizer Checkpoint Downloads: Harmonizer checkpoints can be fetched from the Hugging Face model registry at runtime (default: nvidia/Harmonizer).

  • GSplat as Default Renderer: GSplat is now the default renderer for NRE inference and NRM training. The gRPC --renderer flag still supports default, gsplat, and nrend backends. See :doc:Use the NuRec gRPC API Server <../api/grpc_api_guide>.

  • Semantic Render Outputs: The render CLI adds --output-type, --colorization-max-distance, and --semantics-legend. Camera renders can include semantic_image output, and artifacts export semantic class names and colors metadata for downstream visualization.

  • PPISP Library Update: Adopts the latest PPISP library with improved controller distillation, checkpointing, and HDR responsivity scaling. PPISP USD export adds SPG-runtime and SH-optimized integration modes. The PPISP controller is disabled by default in new configs.

  • Ground-Mesh Road Initialization: Improved camera ground-mesh road initialization for lidarfree training, with reduced multi-GPU initialization stalls and deduplicated ground-mesh work during training.

  • Hyperion 8.1 Eight-Camera Config: New car2sim_8cam production config for Hyperion 8.1 (no cross cameras). See :doc:Configuration <../nurec/configs>.

  • Joint Camera and LiDAR Training: New default config for joint camera and lidar training workflows.

  • Multi-Camera SFM Initialization: Structure-from-motion initialization now supports multi-camera rigs.

  • Dynamic Car Masks: Supports dynamic car masks for arbitrary camera setups during auxiliary data generation and training prep.

  • Render During Training: New Lightning callback renders validation frames during training without a separate post-training step.

  • Asset Harvester Hugging Face Integration: Asset Harvester fetches models from Hugging Face Hub and ships as the GA asset-harvester wheel (v1.0.1). See :doc:Use NuRec with Asset Harvester Output <../nurec/use-ah-assets>.

  • Novel Rig Camera Export: USD and trajectory export supports cameras defined in rig.json that are not present in the reference artifact.

Bug Fixes

  • Harmonizer Multi-GPU Device Placement: Fixed Harmonizer (formerly Difix) model device placement so multi-GPU gRPC rendering places the post-processing model on the correct GPU.

  • Pinhole FOV Clamp: Clamps pinhole field-of-view to the camera’s max_angle to avoid invalid negative focal lengths during NRM rendering.

  • Cubemap Envmap TV Regularization: Fixed total-variation regularization for cubemap environment maps.

  • Ground Mesh Initialization: Fixed ground-mesh initialization edge cases in lidarfree road-layer setup.

  • Config Upgrade Robustness: Config upgrades tolerate null model.post_processing values without failing.

  • Asset Insertion Scale: Preserves asset scale when inserting harvested assets via gRPC or the render pipeline.

  • Asset Extra-Signal Buffers: Expands empty extra_signal buffers on asset insertion to prevent shape mismatches.

  • LiDAR Novel-Pose Zero Rays: Fixed a zero-ray bug when rendering lidar from novel poses.

  • NRend Fisheye Tiling: Fixed tiled-splat artifacts in NRend fisheye camera rendering.

  • LiDAR Validation: Fixed a lidar validation metric routing bug.

  • Instant NuRec PLY Viewer: Fixed ply_viewer crashes when opening Instant NuRec (and other) PLY files.

Known Issues

  • Harmonizer training on multi-GPU nodes: Training with Harmonizer enabled (configs that run Harmonizer distillation or inference during train/val) on multi-GPU systems—especially 8-GPU nodes such as H20—can fail during validation with a CUDA device-mismatch error in the Harmonizer model probe (tensors split across cuda:0 and cuda:N). This is a regression from 26.04. Workaround: run Harmonizer training on a single GPU, or disable training-time Harmonizer and apply Harmonizer at inference via the gRPC server (--enable-harmonizer). See :doc:Use Harmonizer for Post-Processing <../nurec/harmonizer>.

  • gRPC asset replacement rendering: In some gRPC asset-edit scenarios, an inserted asset may not visually replace the target scene vehicle in rendered output (for example, a grey van edit on Hyperion 8.1 scenes). Reported on RTX PRO 6000. A fix is underway for an upcoming release.

On this page