example: add mini camera sample rendering script

python-sdk/nuscenes/scripts/render_mini_camera_samples.py

@@ -0,0 +1,131 @@
+"""
+Render camera samples from the nuScenes v1.0-mini dataset.
+
+This script provides a small, beginner-friendly example for loading the
+nuScenes mini split, selecting a sample, and rendering all available camera
+views for that sample.
+
+Example usage:
+
+    python python-sdk/nuscenes/scripts/render_mini_camera_samples.py \
+        --dataroot /data/sets/nuscenes \
+        --version v1.0-mini \
+        --output-dir /tmp/nuscenes-mini-cameras
+
+The output directory will contain one rendered image per camera channel.
+"""
+
+import argparse
+import os
+from pathlib import Path
+from typing import List
+
+import matplotlib.pyplot as plt
+
+from nuscenes.nuscenes import NuScenes
+
+
+CAMERA_CHANNELS: List[str] = [
+    "CAM_FRONT",
+    "CAM_FRONT_RIGHT",
+    "CAM_BACK_RIGHT",
+    "CAM_BACK",
+    "CAM_BACK_LEFT",
+    "CAM_FRONT_LEFT",
+]
+
+
+def render_camera_samples(
+    dataroot: str,
+    version: str,
+    output_dir: str,
+    sample_index: int,
+) -> None:
+    """
+    Render all available camera channels for a selected nuScenes sample.
+
+    :param dataroot: Path to the nuScenes dataset root.
+    :param version: Dataset version, for example 'v1.0-mini'.
+    :param output_dir: Directory where rendered images will be saved.
+    :param sample_index: Index of the sample to render.
+    """
+    nusc = NuScenes(version=version, dataroot=dataroot, verbose=True)
+
+    if sample_index < 0 or sample_index >= len(nusc.sample):
+        raise ValueError(
+            f"sample_index must be between 0 and {len(nusc.sample) - 1}, "
+            f"but got {sample_index}."
+        )
+
+    output_path = Path(output_dir)
+    output_path.mkdir(parents=True, exist_ok=True)
+
+    sample = nusc.sample[sample_index]
+    print(f"Rendering sample index: {sample_index}")
+    print(f"Sample token: {sample['token']}")
+    print(f"Scene token: {sample['scene_token']}")
+    print(f"Timestamp: {sample['timestamp']}")
+
+    for channel in CAMERA_CHANNELS:
+        if channel not in sample["data"]:
+            print(f"Skipping missing camera channel: {channel}")
+            continue
+
+        sample_data_token = sample["data"][channel]
+        sample_data = nusc.get("sample_data", sample_data_token)
+
+        out_file = output_path / f"{sample_index:04d}_{channel}.png"
+
+        print(f"Rendering {channel}")
+        print(f"  sample_data token: {sample_data_token}")
+        print(f"  source file: {os.path.join(dataroot, sample_data['filename'])}")
+        print(f"  output file: {out_file}")
+
+        nusc.render_sample_data(sample_data_token, out_path=str(out_file))
+        plt.close("all")
+
+    print(f"Done. Rendered camera images are saved in: {output_path}")
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(
+        description="Render camera samples from the nuScenes mini dataset."
+    )
+
+    parser.add_argument(
+        "--dataroot",
+        default="/data/sets/nuscenes",
+        help="Path to the nuScenes dataset root.",
+    )
+
+    parser.add_argument(
+        "--version",
+        default="v1.0-mini",
+        help="nuScenes dataset version to load.",
+    )
+
+    parser.add_argument(
+        "--output-dir",
+        default="/tmp/nuscenes-mini-cameras",
+        help="Directory where rendered camera images will be saved.",
+    )
+
+    parser.add_argument(
+        "--sample-index",
+        type=int,
+        default=0,
+        help="Index of the sample to render.",
+    )
+
+    return parser.parse_args()
+
+
+if __name__ == "__main__":
+    args = parse_args()
+
+    render_camera_samples(
+        dataroot=args.dataroot,
+        version=args.version,
+        output_dir=args.output_dir,
+        sample_index=args.sample_index,
+    )