GitHub - terrafloww/rasteret: Index-first, fast GeoTIFF access layer for ML and analysis. Parse headers once, cache in Parquet, read pixels 20x faster.

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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.

Rasteret separates the workflow into two parts:

  • Control plane: Parquet metadata, cached COG headers, and user columns like labels or splits
  • Data plane: on-demand byte-range reads from the original GeoTIFF/COG objects

Key Features -

  • Easy - three lines from STAC search or Parquet file to a TorchGeo-compatible dataset
  • 20x faster, saves cloud LISTs and GETs - Our custom I/O reads tiles fast with zero STAC/header overhead once a Collection is built
  • Zero data 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 with Collection you can extend.
  • Reproducible - same Parquet index = same records = same results
  • Native dtypes - integer imagery stays integer; missing/edge coverage is represented via fill values (nodata or 0) instead of NaNs
  • Shareable cache - enrich our Collection with your ML splits, patch geometries, custom data points for ML, and share it, don't write folders of image chips!

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.


Installation

Requires Python 3.12+.

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.


Built-in datasets

Rasteret ships with a growing catalog of datasets. Each entry includes license metadata and a commercial_use flag for quick filtering.

Pick an ID, pass it to build() and go:

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

Use your own datasets

  • Use build_from_stac() for any STAC API
  • Use build_from_table() for Parquet files that already contain GeoTIFF/COG URLs

You can also build collections using CLI rasteret collections build read more details here

Here's a guide to add a dataset to rasteret's catalog so everyone benefits. The catalog is open to edit by anyone and will be community-driven.

Each new dataset entry is around ~20 lines of Python pointing to a STAC source or a Parquet source. One PR adds a dataset, every rasteret user sees it in rasteret datasets list on the next release of rasteret.


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, 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=42, crs=32643)
collection.bands  # ['B01', 'B02', ..., 'B12', 'SCL']
len(collection)   # 42


# 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, split, and split_column (when your split field uses a custom name). Use collection.where(expr) when you need an Arrow predicate on custom metadata columns.

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)

Fast arrays (NumPy)

arr = collection.get_numpy(
    geometries=(77.55, 13.01, 77.58, 13.08),
    bands=["B04", "B08"],
)
# shape: [N, C, H, W] for multi-band, [N, H, W] for single-band
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()

Benchmarks

Single request performance (time series query)

Single request performance

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

Single request performance

Single Farm NDVI Time Series (1 Year, Landsat 9)

Run on AWS t3.xlarge (4 CPU) —

Library First Run Subsequent Runs
Rasterio (Multiprocessing) 32 s 24 s
Rasteret 3 s 3 s
Google Earth Engine 10–30 s 3–5 s

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.

Processing time comparison Speedup breakdown

HuggingFace Major-TOMCore 'images-in-parquet' vs Rasteret

Baseline method: datasets.load_dataset(..., streaming=True, filters=...) with local GeoTIFF decode, compared against Rasteret prebuilt index reads. Reproduce with examples/major_tom_benchmark/03_hf_vs_rasteret_benchmark.py.

Patches HF datasets (streaming) Rasteret index+COG Speedup
120 46.83 s 12.09 s 3.88x
1000 771.59 s 118.69 s 6.50x

HF vs Rasteret processing time HF vs Rasteret speedup

For exploration workflows, Major TOM notebooks often use HF streaming generators; Rasteret is optimized for reading the same patches directly from source COGs using an index-first cache.

Notebook: 05_torchgeo_comparison.ipynb

Note

Measured on an EC2 instance in the same region as the data (us-west-2). TorchGeo timings above use 12-30 scenes; HF timings above use 120/1000 patches. Results vary with network conditions. If you run Rasteret on your own workloads, share your numbers on GitHub Discussions or Discord.


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.


Documentation

Full docs at terrafloww.github.io/rasteret:

Getting Started Installation and first steps
Tutorials 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 (custom IO 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