🛰️ Rasteret

Made to beat cold starts.
Index-first access to cloud-native GeoTIFF collections for ML and analysis.

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Every cold start re-parses satellite image metadata over HTTP - per scene, per band. Sentinel-2, Landsat, NAIP, every time. Your colleague did it last Tuesday, CI did it overnight, PyTorch respawns DataLoader workers every epoch. A single project repeats millions of redundant requests before a pixel moves.

Rasteret parses those headers once, caches them in Parquet, and its own reader fetches pixels concurrently with no GDAL in the path. Up to 20x faster on cold starts.

• Easy - three lines from STAC search or Parquet file to a TorchGeo-compatible dataset
• Zero downloads - work with terabytes of imagery while storing only megabytes of metadata
• No STAC at training time - query once at setup; zero API calls during training
• Reproducible - same Parquet index = same records = same results
• Native dtypes - uint16 stays uint16 in tensors; xarray promotes only when NaN fill requires it
• Shareable cache - a 5 MB index captures scene selection, band metadata, and split assignments

Rasteret is an opt-in accelerator that integrates with TorchGeo by returning a standard GeoDataset. Your samplers, DataLoader, xarray workflows, and analysis tools stay the same - Rasteret handles the async tile I/O underneath.

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Installation

uv pip install rasteret

Extras

uv pip install "rasteret[xarray]"       # + xarray output
uv pip install "rasteret[torchgeo]"     # + TorchGeo for ML pipelines
uv pip install "rasteret[aws]"          # + requester-pays buckets (Landsat, NAIP)
uv pip install "rasteret[azure]"        # + Planetary Computer signed URLs

Combine as needed: uv pip install "rasteret[xarray,aws]".

Available extras: xarray, torchgeo, aws, azure, earthdata. See Getting Started for details.

[!NOTE] Requester-pays data (Landsat, etc.): Install the aws extra and configure AWS credentials (aws configure or environment variables). Free public collections like Sentinel-2 on Element84 work without credentials.

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Built-in datasets

Rasteret ships with a growing catalog of datasets, no STAC URLs to memorize:

$ rasteret datasets list
ID                          Name                                       Coverage       License        Auth
earthsearch/sentinel-2-l2a  Sentinel-2 Level-2A                        global         proprietary    none
earthsearch/landsat-c2-l2   Landsat Collection 2 Level-2               global         proprietary    required
earthsearch/naip            NAIP                                       north-america  proprietary    required
earthsearch/cop-dem-glo-30  Copernicus DEM 30m                         global         proprietary    none
earthsearch/cop-dem-glo-90  Copernicus DEM 90m                         global         proprietary    none
pc/sentinel-2-l2a           Sentinel-2 Level-2A (Planetary Computer)   global         proprietary    required
pc/io-lulc-annual-v02       ESRI 10m Land Use/Land Cover               global         CC-BY-4.0      required
pc/alos-dem                 ALOS World 3D 30m DEM                      global         proprietary    required
pc/nasadem                  NASADEM                                    global         proprietary    required
pc/esa-worldcover           ESA WorldCover                             global         CC-BY-4.0      required
pc/usda-cdl                 USDA Cropland Data Layer                   conus          proprietary    required
aef/v1-annual               AlphaEarth Foundation Embeddings (Annual)  global         CC-BY-4.0      none

Each entry includes license metadata sourced from the authoritative STAC API, and a commercial_use flag for quick filtering.

The catalog is open and community-driven. Each dataset entry is ~20 lines of Python: One PR adds a dataset; every user gets access on the next release.

Pick any ID and pass it to build(). Don't see your dataset? Use build_from_stac() for any STAC API, build_from_table() for existing Parquet, or add it to the catalog so everyone benefits.

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Quick start

Build a Collection

import rasteret

collection = rasteret.build(
    "earthsearch/sentinel-2-l2a",
    name="s2_training",
    bbox=(77.5, 12.9, 77.7, 13.1),
    date_range=("2024-01-01", "2024-06-30"),
)

build() picks the dataset from the catalog, queries the STAC API, parses COG headers, and caches everything as Parquet. The next run loads in milliseconds.

Inspect and filter

collection        # Collection('s2_training', source='sentinel-2-l2a', bands=13, records=47, crs=32643)
collection.bands  # ['B01', 'B02', ..., 'B12', 'SCL']
len(collection)   # 47


# Filter in memory — no network calls
filtered = collection.subset(cloud_cover_lt=15, date_range=("2024-03-01", "2024-06-01"))

subset() accepts cloud_cover_lt, date_range, bbox, geometries, and split. For raw Arrow expressions, use collection.where(expr).

ML training (TorchGeo)

from torch.utils.data import DataLoader
from torchgeo.samplers import RandomGeoSampler
from torchgeo.datasets.utils import stack_samples

dataset = collection.to_torchgeo_dataset(
    bands=["B04", "B03", "B02", "B08"],
    chip_size=256,
)

sampler = RandomGeoSampler(dataset, size=256, length=100)
loader = DataLoader(dataset, sampler=sampler, batch_size=4, collate_fn=stack_samples)

Analysis (xarray)

ds = collection.get_xarray(
    geometries=(77.55, 13.01, 77.58, 13.08),  # bbox, Arrow array, Shapely, or WKB
    bands=["B04", "B08"],
)
ndvi = (ds.B08 - ds.B04) / (ds.B08 + ds.B04)

Going further

What	Where
Datasets not in the catalog	build_from_stac()
Parquet with COG URLs (Source Cooperative, STAC GeoParquet, custom)	build_from_table(path, name=...)
Multi-band COGs (AEF embeddings, etc.)	AEF Embeddings guide
Authenticated sources (PC, requester-pays, Earthdata, etc.)	Custom Cloud Provider
Share a Collection	collection.export("path/") then rasteret.load("path/")
Filter by cloud cover, date, bbox	collection.subset()

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Benchmarks

Single request performance

Processing pipeline: Filter 450,000 scenes -> 22 matches -> Read 44 COG files

Cold-start comparison with TorchGeo

Same AOIs, same scenes, same sampler, same DataLoader. Both paths output identical [batch, T, C, H, W] tensors. TorchGeo runs with its recommended GDAL settings for best-case remote COG performance.

Scenario	rasterio/GDAL path	Rasteret path	Ratio
Single AOI, 15 scenes	9.08 s	1.14 s	8x
Multi-AOI, 30 scenes	42.05 s	2.25 s	19x
Cross-CRS boundary, 12 scenes	12.47 s	0.59 s	21x

The difference comes from how headers are accessed: the rasterio/GDAL path re-parses IFDs over HTTP on each cold start, while Rasteret reads them from a local Parquet cache. See Benchmarks for full methodology.

Notebook: 05_torchgeo_comparison.ipynb

Note

Measured on 12-30 Sentinel-2 scenes on an EC2 instance in the same region as the data (us-west-2). Results vary with network conditions. If you run Rasteret on your own workloads, share your numbers on GitHub Discussions or Discord.

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Scope and stability

Area	Status
STAC + COG scene workflows	Stable
Parquet-first workflows (build_from_table())	Stable
Multi-band / planar-separate COGs (band_index)	Stable
Multi-cloud (S3, Azure Blob, GCS)	Stable
Dataset catalog	Stable
TorchGeo adapter	Stable

Rasteret is optimized for remote, tiled GeoTIFFs (COGs). It also works with local tiled GeoTIFFs for indexing, filtering, and sharing collections. Non-tiled TIFFs and non-TIFF formats are best handled by TorchGeo or rasterio.

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Documentation

Full docs at terrafloww.github.io/rasteret:

Getting Started	Installation and first steps
Tutorials	Six hands-on notebooks
How-To Guides	Task-oriented recipes
API Reference	Auto-generated from source
Architecture	Design decisions
Ecosystem Comparison	Rasteret vs TACO, async-geotiff, virtual-tiff

Contributing

The catalog grows with community help:

• Add a dataset: write a ~20 line descriptor in catalog.py, open a PR. See prerequisites and guide
• Improve docs: fix a typo, add an example, clarify a section
• Build something new: ingest drivers, cloud backends, readers. See Architecture

All contributions are welcome. See Contributing for dev setup and we are happy to discuss all aspects of library. Ideas welcome on GitHub Discussions or join our Discord to just chat.

Technical notes

GeoParquet and Parquet Raster

Rasteret Collections are written as GeoParquet 1.1 (WKB footprint geometry

• geo metadata; coordinates in CRS84). Parquet is adding native GEOMETRY/GEOGRAPHY logical types and GeoParquet 2.0 is evolving alongside that; Rasteret tracks this and plans to adopt when ecosystem support stabilizes.

GeoParquet also has an alpha "Parquet Raster" draft for storing raster payloads in Parquet. Rasteret does not write Parquet Raster files: pixels stay in GeoTIFF/COGs, and Parquet stays the index.

TorchGeo interop

RasteretGeoDataset is a standard TorchGeo GeoDataset subclass. It honors the full GeoDataset contract:

• __getitem__(GeoSlice) returns {"image": Tensor, "bounds": Tensor, "transform": Tensor}
• index is a GeoPandas GeoDataFrame with an IntervalIndex named "datetime"
• crs and res are set correctly for sampler compatibility
• Works with RandomGeoSampler, GridGeoSampler, and any custom sampler
• Works with IntersectionDataset and UnionDataset for dataset composition

Rasteret replaces the I/O backend (async obstore instead of rasterio/GDAL) but speaks the same interface. Your samplers, DataLoader, transforms, and training loop do not change.

Rasteret can also add extra keys to the sample dict (e.g. label from a metadata column) without breaking interop - TorchGeo ignores unknown keys.

TorchGeo's rasterio/GDAL-backed RasterDataset remains the right choice for non-tiled TIFFs and non-TIFF formats.

License

Code: Apache-2.0