New to Claude Skills? Learn how to install them →

nvidia on GitHub

VSS Generate Video Calibration

OfficialFree

Automate video calibration with AutoMagicCalib.

by nvidia2.8k stars on nvidia/skills
Updated Aug 7, 2026
Get this skill

Free · Opens the source repo

What VSS Generate Video Calibration does

The VSS Generate Video Calibration skill allows users to run AutoMagicCalib on various input sources, including local MP4 files, RTSP streams, or a bundled sample dataset. This skill is particularly useful for developers and engineers working with video calibration who need to automate the calibration process efficiently. By leveraging the skill, users can deploy the AMC microservice and manage the calibration workflow seamlessly through a REST API.

To get started, users must follow specific routing tables and workflows that guide them through the calibration process. Each input mode has its own reference documentation, ensuring that users can quickly find the necessary steps for their specific use case. For instance, users can choose to calibrate from local video files, live RTSP streams, or test the bundled sample dataset, making it versatile for different scenarios.

The skill also includes troubleshooting guidance for common issues that may arise during the calibration process, such as connection errors or insufficient GPU memory. This support helps users resolve problems quickly and maintain an efficient workflow. Additionally, the skill provides examples and evaluations that demonstrate its capabilities, allowing users to validate their setup before proceeding with actual calibration tasks.

Overall, this skill is designed for users who require a robust solution for video calibration, providing a streamlined process from deployment to execution. Its focus on automation and integration with existing workflows makes it a valuable tool for anyone working in video processing or machine learning applications.

When to use it

Use this skill when you need to calibrate videos or RTSP streams using AutoMagicCalib and require the deployment of the AMC microservice.

When not to use it

This skill is not suitable for non-AutoMagicCalib calibration tasks or runtime analytics.

What you can build with it

Calibrating Local Video Files

Use this skill to automate the calibration of local MP4 video files, streamlining your workflow.

Deploying AMC Microservice

Quickly deploy the AMC microservice to support your video calibration tasks with just a few commands.

Testing with Sample Dataset

Verify your AMC installation by running calibration on the provided sample dataset, ensuring everything is set up correctly.

How to install VSS Generate Video Calibration

View source

1. Install with the skills CLI

npx skills add nvidia/skills/vss-generate-video-calibration --agent claude-code

2. Or install it manually

Download the skill folder and drop it into ~/.claude/skills/ for all projects, or .claude/skills/ to scope it to one repo. Restart Claude Code so it picks up the new skill.

Anthropic's agentic coding CLI, and the reference implementation of Agent Skills. Drop a skill folder into ~/.claude/skills and Claude Code loads it automatically whenever a task matches the skill's description. Claude Code docs

Inside SKILL.md

Written by nvidia

Purpose

Run AutoMagicCalib end-to-end on local files, RTSP streams, or the bundled sample dataset and (when needed) deploy the AMC microservice.

Instructions

Follow the routing tables and step-by-step workflows below. Each section that ends in workflow, quick start, or flow is intended to be executed top-to-bottom. Detailed reference material lives in references/; load only the reference needed for the selected input mode.

Examples

Worked end-to-end examples are kept under evals/ (each *.json manifest contains a runnable scenario) and inline in the per-workflow curl blocks below. Run a Tier-3 evaluation with nv-base validate <this-skill-dir> --agent-eval to replay them.

Limitations

  • Requires the matching VSS profile / microservice to be deployed and reachable from the caller.
  • NGC-hosted models and NIMs may be subject to rate-limits, GPU memory requirements, and license restrictions.
  • Concurrency, GPU memory, and storage limits depend on the host hardware and the profile's compose file.

Troubleshooting

  • Error: REST call returns connection refused. Cause: target microservice not running. Solution: probe /docs or /health; redeploy via vss-deploy-profile or the matching vss-deploy-* skill.
  • Error: HTTP 401/403 from NGC pulls. Cause: missing/expired NGC_CLI_API_KEY. Solution: docker login nvcr.io and re-export the key before retrying.
  • Error: container OOM or model fails to load. Cause: insufficient GPU memory for the selected profile. Solution: switch to a smaller variant or free GPUs via docker compose down.

VSS Generate Video Calibration

Run AutoMagicCalib over one of three input sources and drive the calibration through the microservice REST API. The input-resolution work differs per source; everything from verify_project onward is identical and lives in this file. Pick the right input-mode reference and pair it with the Shared Calibration Tail below.

Shared helper references are loaded only when needed:

Input Routing

Match the user's request to a mode, then load that mode's reference for input collection, mode-specific API calls, and the full Python script.

User says / hasModeReference
"launch AMC" / "deploy auto-calibration" / "set up auto-magic-calib" / "start AMC microservice"deployreferences/deploy-auto-calibration-service.md
"calibrate my videos" / "calibrate from video files" / local cam_*.mp4 filesvideosreferences/videos.md
"calibrate RTSP streams" / "calibrate from live cameras" / live RTSP URLsrtspreferences/rtsp.md
"test sample dataset" / "verify AMC install" / "launch and test"sample-datasetreferences/sample-dataset.md

Disambiguation rule: if the user is asking to launch / deploy / set up AMC (no calibration verb) → deploy. If they provide RTSP URLs → rtsp. If they mention local files / a videos directory → videos. If they ask to verify install or test the bundled sample → sample-dataset. Combined intents (e.g. "launch AMC and calibrate my videos") → walk deploy first, then the calibration mode. When ambiguous, ask via AskUserQuestion.

Prerequisites (shared across calibration modes)

  • AMC microservice + UI running. If not, walk references/deploy-auto-calibration-service.md first.
  • Microservice reachable at http://<HOST_IP>:${VSS_AUTO_CALIBRATION_PORT:-8010}/v1/ready{"code":0,...}.
  • Projects directory writable by the container user. If you didn't just deploy (so Step 5 of the deploy reference hasn't run), confirm the write test in references/deploy-auto-calibration-service.md § Step 5 — otherwise the first create_project returns [Errno 13] Permission denied.
  • Python 3 with requests installed (each input-mode reference includes a self-healing venv fallback for direct runs).

Mode-specific prerequisites (VIOS for rtsp, sample zip for sample-dataset) live in the respective references.

Shared Calibration Tail

The verify → calibrate → poll → results sequence is identical regardless of input mode. After the mode-specific reference has uploaded videos / ingested RTSP clips / uploaded the bundled sample, run this tail. Use references/calibration-tail.md for the shared Python snippet.

Step A — Verify Project

POST /v1/verify_project/<project_id>

Response: {"project_state": "READY"} — must be READY before calibrating. If not READY, re-check that videos + alignment + layout are present (either via API or via UI manual alignment).

Step B — Start Calibration

Confirm the plan before calibrating. Whether the settings file and detector were auto-detected or asked, present a short summary and confirm via AskUserQuestion before the POST /calibrate. The resolved values are the defaults, so confirming is one click — but the user can switch the detector or skip an auto-detected settings file. Summarize:

  • Detectorresnet or transformer (the value to be sent).
  • Calibration settings — the file being applied (path), or default parameters (with the option to tune them in the UI first — see below).
  • Optional overrides — ground-truth zip and focal lengths, if any.

The sample-dataset install-check run uses a fixed resnet and can proceed without this confirmation.

POST /v1/calibrate/<project_id>
Content-Type: application/json

{"detector_type": "resnet"}   # or "transformer"

detector_type is a separate /calibrate parameter — not consumed by /v1/config/<id>. If the user provided a calibration settings file, parse it for "detector" / "detector_type" and use that value. If the file doesn't specify one, the default (resnet) is the value shown in the confirmation above — the user can switch it there before calibrating. If there's no settings file at all, ask the user via AskUserQuestion:

  • resnet — default, fast.
  • transformer — slower, better under heavy occlusion.

UI Step 3 (Parameters) does NOT cover detector choice; never assume the user picked one in the UI.

Also when there's no settings file, ask whether to tune the calibration parameters first (AskUserQuestion):

  • Proceed with the default parameters — well-suited to typical warehouse scenes; recommended unless the user has specific tuning in mind.
  • Adjust parameters in the UI first — open the project, go to Step 3: Parameters, change values, and click Save; then continue.

Wait for the user's choice — and, if they choose to tune, for them to confirm they've Saved — before calling /calibrate.

Step C — Poll for Completion

GET /v1/get_project_info/<project_id>

Poll every 10 s. project_info.project_state:

StateMeaning
RUNNINGCalibration in progress
COMPLETEDFinished
ERRORFailed — pull log via GET /v1/amc/calibrate/<id>/log

When calibration starts, surface the project ID, the UI URL (http://<HOST_IP>:${VSS_AUTO_CALIBRATION_UI_PORT:-5000}), and the log endpoint so the user can watch progress while the run proceeds. During RUNNING, emit a progress line at least once a minute with elapsed time so a long run doesn't look stalled. On ERROR, fetch and show the last lines of GET /v1/amc/calibrate/<id>/log before stopping. Live logs can also be streamed via GET /v1/calibrate/<project_id>/log/<type>/stream.

Typical time: 10–60 min (your-own videos), 10–30 min (bundled sample).

Step D — Results

GET /v1/get_project_info/<project_id>                    # project state
GET /v1/result/<project_id>/evaluation_statistics        # only if GT uploaded
GET /v1/result/<project_id>/overlay_image                # visual overlay (PNG)
GET /v1/amc/calibrate/<project_id>/log                   # calibration log

Evaluation response includes Average L2 distance(m) and Average reprojection error 0(px). Evaluation metrics are produced only when a ground-truth GT.zip was uploaded — a missing evaluation_statistics result is normal otherwise and is not the end of result reporting.

After COMPLETED, always give the user a way to review the result for that exact project, regardless of whether metrics exist:

  • UIhttp://<HOST_IP>:${VSS_AUTO_CALIBRATION_UI_PORT:-5000}; open the project, then the Results page to view the overlay.
  • Overlay image on disk${VSS_APPS_DIR}/services/auto-calibration/projects/project_<id>/output/multi_view_results/BA_output/results_ba_scaled_world/overlay_img_*.png (single-camera projects use output/single_view_results/cam_00/verification_map_overlay.png).
  • Project files${VSS_APPS_DIR}/services/auto-calibration/projects/project_<id>/.

Step E — VGGT Refinement

After the AMC run completes, always check vggt_state in project info. VGGT model staging is optional during setup and must not block the AMC result, but post-AMC handling follows the state:

  • If vggt_state == "READY" and the user explicitly requested VGGT refinement or staged VGGT during this setup flow, run VGGT refinement without asking again.
  • If vggt_state == "READY" but VGGT was already staged before this request and the user has not asked for VGGT-refined output, ask via AskUserQuestion whether to run refinement before starting it.
  • If VGGT is not ready, skip refinement and mention that VGGT refinement is available after staging the model (see references/deploy-auto-calibration-service.md Step 2).
POST /v1/vggt/calibrate/<project_id>
GET  /v1/get_project_info/<project_id>                    # poll vggt_state
GET  /v1/vggt_results/<project_id>/evaluation_statistics  # VGGT metrics

Settings File + Detector Pattern

Optional across all three modes. When the user provides a JSON settings file (typically exported from UI Step 3 Download), POST it verbatim:

POST /v1/config/<project_id>
Content-Type: application/json

<file contents, posted as-is>

The file replaces what the user would otherwise tune in UI Step 3 (rectification, bundle-adjustment, evaluation knobs, detector, …). After a successful POST, also parse the file for "detector" / "detector_type" — if it's "resnet" or "transformer", use that value for the /calibrate call in Step B (detector is a separate API parameter, not consumed by /config).

Non-2xx is surfaced — do not silently fall back. Skip this call entirely if the user chose the UI-fallback path.

UI Fallback Pattern

When alignment / layout files aren't on disk, direct the user to the appropriate AMC UI step:

  • Settings missing → "Open UI project <project_id>, go to Step 3: Parameters, tune via the settings dialog (or accept defaults), click Save." Also: before the /calibrate call, ask the user via AskUserQuestion whether to use the resnet or transformer detector — Step 3 doesn't cover detector choice.
  • Layout missing → "Open UI project <project_id>, go to Step 2: Video Configuration, upload layout.png only (do NOT re-upload videos — they're already attached via API/RTSP), click Save."
  • Alignment missing → "Open UI project <project_id>, go to Step 4: Alignment, either upload alignment_data.json or mark correspondence points on the layout, click Save."

Wait for user confirmation. For alignment/layout, verify on disk before continuing:

# Project state lives under $VSS_APPS_DIR/services/auto-calibration/projects
# (the path bind-mounted into the MS container in
#  deploy/docker/services/auto-calibration/ms/compose.yml).
HOST_PROJECTS="${VSS_APPS_DIR}/services/auto-calibration/projects"

ls "$HOST_PROJECTS/project_<project_id>/manual_adjustment/"
# Expected: alignment_data.json, layout.png

Success Criteria

  • project_state == "COMPLETED" after polling.
  • If manual alignment was used: ${VSS_APPS_DIR}/services/auto-calibration/projects/project_<id>/manual_adjustment/ contains alignment_data.json + layout.png.
  • If GT was uploaded: evaluation returns typical thresholds (Average L2 distance(m) < 1.5, Average reprojection error 0(px) < 5 for your data; < 10 for the bundled sample).
  • No ERROR state.

Key Output Files

Under ${VSS_APPS_DIR}/services/auto-calibration/projects/project_<project_id>/:

project_<project_id>/
├── manual_adjustment/
│   ├── alignment_data.json
│   └── layout.png
├── output/
│   ├── single_view_results/cam_XX/
│   │   ├── camInfo_hyper_XX.yaml
│   │   └── trajDump_Stream_0_3d.txt
│   ├── multi_view_results/BA_output/results_ba/
│   │   ├── initial/camInfo_XX.yaml
│   │   └── refined/camInfo_XX.yaml          # ← final calibration
│   └── multi_view_results/BA_output/results_ba_scaled_world/
│       └── overlay_img_XX.png               # ← visual overlay for review
└── calibration.log

Cross-cutting Troubleshooting

Mode-specific issues live in each reference's own troubleshooting table.

IssueFix
verify_project state not READYConfirm videos uploaded/ingested and alignment + layout are present (either via API or via UI manual alignment). Mode-specific upload steps in the reference.
Manual alignment files missing after UI stepUser didn't click Save; also verify ${VSS_APPS_DIR}/services/auto-calibration/projects/project_<id>/manual_adjustment/ exists.
Calibration stuck RUNNING > 90 minGET /v1/amc/calibrate/<id>/log — usually insufficient tracklets (scene too static). See "Custom Dataset" guidelines in root README.md.
Immediate ERROR stateCheck video naming: must be cam_00.mp4, cam_01.mp4, … contiguous (videos mode) / camera_name labels (RTSP mode).
Low L2 but high reprojectionProvide explicit focal_length override during input upload (see videos / rtsp references).
VGGT INIT, never READYVGGT model not loaded — see references/deploy-auto-calibration-service.md Step 2.
Upload timeoutLarge videos — bump timeout=300 to e.g. 600 in the per-mode Python script.
Port scan finds no backendBackend not running — walk references/deploy-auto-calibration-service.md first.

For Downstream Skills — MV3DT Export

Downstream consumers (e.g. a Multi-View 3D Tracking skill owned by another team) fetch the MV3DT-format calibration output directly from the microservice. This skill returns the project_id; the downstream skill calls:

GET /v1/result/{project_id}/mv3dt_result?result_type=amc
# Response: application/zip — mv3dt_output.zip containing transforms.yml

For VGGT-refined output (only available if VGGT ran to COMPLETED, see Step E):

GET /v1/result/{project_id}/mv3dt_result?result_type=vggt
# Response: application/zip — vggt_mv3dt_output.zip

Downstream skill flow:

  1. Call this skill with the user's inputs; capture the printed project_id.
  2. Wait for the skill to return (it polls until COMPLETED internally).
  3. GET /v1/result/{project_id}/mv3dt_result?result_type=amc — save the ZIP locally.
  4. If VGGT also ran, optionally fetch ?result_type=vggt for the refined MV3DT.

Related Skills

Root README.md "Custom Dataset" and "Calibration Workflow (UI)" sections document input-video guidelines and the UI-driven alternative to this API flow.

bump:1

Frequently asked questions about VSS Generate Video Calibration

Similar skills