Tao train sparse4d
Sparse4D for multi-camera temporal 3D object detection and tracking. Uses sparse queries with deformable attention across camera views and time for end-to-end 3D perception, with an instance bank for temporal tracking. Use when training, evaluating, exporting, quantizing, or running inference for a TAO Sparse4D model. Trigger phrases include "train Sparse4D", "multi-camera 3D detection", "temporal 3D tracker", "sparse query 3D perception".From its SKILL.md
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SKILL.md
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Sparse4D
Sparse4D for multi-camera temporal 3D object detection and tracking. Uses sparse queries with deformable attention across camera views and time for end-to-end 3D perception. Includes instance bank for temporal tracking.
Use a pretrained ResNet-101 backbone when one is available by setting
train.pretrained_model_path. For local smoke validation, Sparse4D training
can run with an empty train.pretrained_model_path, but production runs should
still use a compatible PTM.
Dataclass Schemas
Generated TAO Core schemas are packaged in schemas/<action>.schema.json, with schemas/manifest.json listing available actions. Each generated schema also emits references/spec_template_<action>.yaml from the schema top-level default field. AutoML enablement is declared at the model layer in references/skill_info.yaml via automl_enabled. Runnable AutoML still requires schemas/train.schema.json and references/spec_template_train.yaml to exist and parse. Use the packaged train schema for automl_default_parameters, automl_disabled_parameters, defaults, min/max bounds, enums, option weights, math conditions, dependencies, and popular parameters. Do not expect ~/tao-core at runtime; maintainers regenerate schemas/templates before packaging the skill bank.
Train Action Policy
This model is AutoML-enabled at the model layer. Before handling any train-stage request, read references/skill_info.yaml and resolve the run override from either an explicit automl_policy value or the user's workflow request. Use automl_policy: on by default and only expose on / off in new launch prompts. Treat phrases like "turn off AutoML", "disable AutoML", "no HPO", or "plain training" as automl_policy: off for this run only. When automl_policy: on, automl_enabled: true, and both schemas/train.schema.json and references/spec_template_train.yaml are packaged, route the train action through tao-skill-bank:tao-run-automl by default with this model's skill_dir. Preserve workflow/application overrides for datasets, specs, output directories, GPU/platform settings, parent checkpoints, and automl_policy. Use direct model training only when automl_policy: off or the packaged train schema/template is missing; in the missing-schema case, report that AutoML is enabled but not runnable for this model until schemas are generated.
Non-train actions such as evaluate, inference, export, and deploy flows stay in this model skill. The per-run automl_policy override does not change model metadata.
Training Requirements
- Dataset type: sparse4d
- Formats: ovpkl
- Monitoring metric: val_mAP
- Current TAO Sparse4D training emits this value in status/logs as
img_bbox_NuScenes/mAPandmAP; AutoML metric extractors should treat those emitted keys as aliases forval_mAP. Multi-fidelity AutoML algorithms such as Hyperband, ASHA, and BOHB may promote a checkpoint to a resume job that completes without emitting a freshval_mAPalias. In that case, compare AutoML's carried metric to the source rung job that emittedimg_bbox_NuScenes/mAPormAP, while still verifying that the promoted job resumed from the explicit epoch/step checkpoint, produced a real checkpoint, and is usable for evaluate/inference.
Per-Action Dataset Requirements
| Action | Spec Key | Source | Files | List? |
|---|---|---|---|---|
| dataset_convert | aicity.root | id | No | |
| evaluate | dataset.data_root | eval_dataset | (from convert job, spec: aicity.split) | No |
| evaluate | model.head.instance_bank.anchor | train_datasets | /results/{dataset_convert_job_id}/anchor_init.npy | No |
| evaluate | dataset.train_dataset.ann_file | train_datasets | (from convert job, spec: aicity.split) | No |
| evaluate | dataset.val_dataset.ann_file | eval_dataset | (from convert job, spec: aicity.split) | No |
| evaluate | dataset.test_dataset.ann_file | inference_dataset | (from convert job, spec: aicity.split) | No |
| export | model.head.instance_bank.anchor | train_datasets | /results/{dataset_convert_job_id}/anchor_init.npy | No |
| inference | dataset.data_root | inference_dataset | (from convert job, spec: aicity.split) | No |
| inference | model.head.instance_bank.anchor | train_datasets | /results/{dataset_convert_job_id}/anchor_init.npy | No |
| inference | dataset.train_dataset.ann_file | train_datasets | (from convert job, spec: aicity.split) | No |
| inference | dataset.val_dataset.ann_file | eval_dataset | (from convert job, spec: aicity.split) | No |
| inference | dataset.test_dataset.ann_file | inference_dataset | (from convert job, spec: aicity.split) | No |
| quantize | dataset.data_root | train_datasets | (from convert job, spec: aicity.split) | No |
| quantize | model.head.instance_bank.anchor | train_datasets | /results/{dataset_convert_job_id}/anchor_init.npy | No |
| quantize | dataset.train_dataset.ann_file | train_datasets | (from convert job, spec: aicity.split) | No |
| quantize | dataset.val_dataset.ann_file | eval_dataset | (from convert job, spec: aicity.split) | No |
| quantize | dataset.test_dataset.ann_file | inference_dataset | (from convert job, spec: aicity.split) | No |
| quantize | dataset.quant_calibration_dataset.images_dir | train_datasets | No | |
| train | dataset.data_root | train_datasets | (from convert job, spec: aicity.split) | No |
| train | model.head.instance_bank.anchor | train_datasets | /results/{dataset_convert_job_id}/anchor_init.npy | No |
| train | dataset.train_dataset.ann_file | train_datasets | (from convert job, spec: aicity.split) | No |
| train | dataset.val_dataset.ann_file | eval_dataset | (from convert job, spec: aicity.split) | No |
| train | dataset.test_dataset.ann_file | inference_dataset | (from convert job, spec: aicity.split) | No |
Typical Spec Overrides
Data source overrides are mandatory for every action — the agent MUST construct data source paths from the Per-Action Dataset Requirements table above and include them in spec_overrides.
S3_TRAIN = "s3://bucket/data/train"
S3_EVAL = "s3://bucket/data/eval"
CONVERTED_SCENE = "<scene-from-converter>" # e.g. "subsetscene+bev-sensor-random-0"
train (mandatory data sources):
CONVERTED = "s3://bucket/results/<dataset_convert_job_id>"
{
"train.num_epochs": 30,
"train.checkpoint_interval": 10,
"train.validation_interval": 10,
"train.num_gpus": 1,
"dataset.sequences.split_num": 90,
"dataset.train_dataset.sequences_split_num": 90,
"dataset.data_root": f"{S3_TRAIN}/train",
"model.head.instance_bank.anchor": f"{CONVERTED}/anchor_init.npy",
"dataset.train_dataset.ann_file": f"{CONVERTED}/train/{CONVERTED_SCENE}_infos_train.pkl",
"dataset.val_dataset.ann_file": f"{CONVERTED}/val/{CONVERTED_SCENE}_infos_val.pkl",
"dataset.test_dataset.ann_file": f"{CONVERTED}/test/{CONVERTED_SCENE}_infos_test.pkl",
}
evaluate (mandatory data sources):
CONVERTED = "s3://bucket/results/<dataset_convert_job_id>"
{
"dataset.data_root": f"{S3_EVAL}/val",
"model.head.instance_bank.anchor": f"{CONVERTED}/anchor_init.npy",
"dataset.train_dataset.ann_file": f"{CONVERTED}/train/{CONVERTED_SCENE}_infos_train.pkl",
"dataset.val_dataset.ann_file": f"{CONVERTED}/val/{CONVERTED_SCENE}_infos_val.pkl",
"dataset.test_dataset.ann_file": f"{CONVERTED}/test/{CONVERTED_SCENE}_infos_test.pkl",
}
export (mandatory data sources):
CONVERTED = "s3://bucket/results/<dataset_convert_job_id>"
{
"model.head.instance_bank.anchor": f"{CONVERTED}/anchor_init.npy",
}
inference (mandatory data sources):
CONVERTED = "s3://bucket/results/<dataset_convert_job_id>"
{
"dataset.data_root": f"{S3_EVAL}/test",
"model.head.instance_bank.anchor": f"{CONVERTED}/anchor_init.npy",
"dataset.train_dataset.ann_file": f"{CONVERTED}/train/{CONVERTED_SCENE}_infos_train.pkl",
"dataset.val_dataset.ann_file": f"{CONVERTED}/val/{CONVERTED_SCENE}_infos_val.pkl",
"dataset.test_dataset.ann_file": f"{CONVERTED}/test/{CONVERTED_SCENE}_infos_test.pkl",
}
quantize (mandatory data sources):
CONVERTED = "s3://bucket/results/<dataset_convert_job_id>"
{
"dataset.data_root": f"{S3_TRAIN}/train",
"model.head.instance_bank.anchor": f"{CONVERTED}/anchor_init.npy",
"dataset.train_dataset.ann_file": f"{CONVERTED}/train/{CONVERTED_SCENE}_infos_train.pkl",
"dataset.val_dataset.ann_file": f"{CONVERTED}/val/{CONVERTED_SCENE}_infos_val.pkl",
"dataset.test_dataset.ann_file": f"{CONVERTED}/test/{CONVERTED_SCENE}_infos_test.pkl",
"dataset.quant_calibration_dataset.images_dir": f"{S3_TRAIN}",
}
See references/local_docker_conversion.md for local-docker conversion roots and mounts, H5 depth-path normalization, converted annotation filenames, smoke-run max_num_cams/anchor contracts for export compatibility, and converted-artifact verification before train/evaluate/inference.
Eval Dataset
Optional. Val/test splits configured via dataset ann_file paths.
Important Parameters
- model.backbone: Backbone. Default resnet_101.
- model.neck.out_channels: FPN output channels. Default 256. num_outs=4.
- model.input_shape: Input image shape [W, H]. Default [1408, 512].
- model.head.num_output: Number of detection output queries. Default 300.
- model.head.num_decoder: Number of decoder layers. Default 6.
- model.head.temporal: Enable temporal reasoning. Default True.
- model.head.instance_bank.num_anchor: Instance bank anchors. Default 900.
- model.head.instance_bank.num_temp_instances: Temporal instance count. Default 600.
- model.depth_branch.loss_weight: Depth supervision loss weight. Default 0.2.
- dataset.batch_size: Per-GPU batch size. Default 2.
- dataset.num_frames: Sequence length. Default 200.
- dataset.classes: Detection classes. Default [person, gr1_t2, agility_digit, nova_carter]. num_ids=70 for tracking.
- train.optim.lr: Learning rate. Default 5e-5. img_backbone lr_mult=0.2.
- train.lr_scheduler: Cosine scheduler with linear warmup (500 iters, ratio 0.333).
- train.grad_clip.max_norm: Gradient clipping. Default 25.
- train.precision: Options: bf16, fp16, fp32. Default bf16.
- evaluate.metrics: Eval metrics. Default ["detection"]. Optional tracking evaluation.
- evaluate.tracking.enabled: Enable tracking evaluation. tracking_threshold=0.2.
Multi-GPU / Multi-Node
Launch method: Lightning-managed (single python process, Lightning spawns workers).
| Spec Key | Description | Default |
|---|---|---|
train.num_gpus | Number of GPUs | 1 |
train.gpu_ids | GPU device indices | [0] |
train.num_nodes | Number of nodes | 1 |
- Multi-GPU strategy:
ddp_find_unused_parameters_true(no fsdp support) sync_batchnormis always enabled (True)- Iterations per epoch computed as:
num_frames * num_bev_groups / (num_nodes * num_gpus * batch_size) - Scaling: When increasing GPUs, effective batch size grows and iterations-per-epoch shrinks proportionally
Multi-node env vars (set by orchestrator): WORLD_SIZE, NODE_RANK, MASTER_ADDR, MASTER_PORT, NUM_GPU_PER_NODE.
Hardware
Minimum 2 GPU(s), recommended 8 GPU(s). 40GB+ (A100 recommended) VRAM per GPU. Multi-camera temporal model is memory intensive. bf16 required for practical training. Multi-GPU strongly recommended. Instance bank requires substantial memory for temporal reasoning.
Error Patterns
dataset_convert required: Must run dataset_convert first to produce annotation pickles and anchor_init.npy.
dataset_convert container/command: Sparse4D conversion is an AICity to
OVPKL annotations conversion. Launch dataset_convert with the action-level
tao_toolkit.data_services image and annotations convert -e {config_path};
do not use the PyTorch sparse4d CLI for conversion. Train/evaluate/export/
inference still use the model-level PyTorch image.
Stable raw-data path: The AICity to OVPKL converter writes image paths into
the generated pickle files. Keep aicity.root at /data/aicity_root during
conversion, then point dataset.data_root at the split folder, for example
/data/aicity_root/train for training or /data/aicity_root/val for
evaluation. This preserves the converter's absolute RGB paths and relative
depth paths.
H5 depth tuple mismatch: If training fails with an H5 path error where the
trainer tries to open a camera directory such as
/data/aicity_root/train/<scene>/Camera, run
models/sparse4d/scripts/normalize_depth_paths.py --data-root <host-aicity-root>/train <converted-ann-dir>
after dataset_convert and before train/evaluate/inference. The helper rewrites
converted depth_map_path tuples to point at
<scene>/depth_maps/<camera>.h5 with the H5 dataset key basename.
Missing anchor file: Set model.head.instance_bank.anchor to the anchor_init.npy path from dataset_convert results.
Temporal OOM: Reduce dataset.num_frames or dataset.batch_size if running out of memory during temporal training.
Quantize image compatibility: The model-skill wiring should pass
quantize.model_path through the parent-model resolver, and checkpoint handoff
should select the exact epoch/step checkpoint just like evaluate, inference,
export, and resume. TorchAO checkpoint quantization passes in the
validation-fixes-20260525 PyT image and writes
quantized_model_torchao.pth. Older 7.0.0-rc PyT images may fail inside the
Sparse4D quantize entrypoint or lack ONNX quantization dependencies; do not
remove or skip the advertised quantize action if that occurs. Report the
container/image failure and keep the exact checkpoint path visible.
Spec Param / Parent Model Inference
See references/spec_param_inference.md for the model-specific inference mappings from TAO Core sparse4d.config.json (the per-action spec-field to inference-function table) and the parent_model/parent_job_id checkpoint-resolution rules that generated runners apply with SDK helpers before create_job().
What ships with it: 20 files
640.6 KB alongside SKILL.md
evals/
- evals.json804 B
references/
schemas/
- dataset_convert.schema.json10.9 KB
- evaluate.schema.json111.2 KB
- export.schema.json110.8 KB
- inference.schema.json111.3 KB
- manifest.json15.9 KB
- quantize.schema.json107.3 KB
- train.schema.json107.3 KB
- BENCHMARK.md4.0 KB
- skill-card.md3.8 KB
- skill.oms.sig8.3 KB