Pixxel Imagery 101

  • Atmospheric Correction - piSOFIT model

    piSOFIT is Pixxel’s customized implementation of NASA JPL’s open-source ISOFIT (Imaging Spectrometer Optimal Fitting) model, optimized for Firefly and Honeybee hyperspectral data.

     

    Methodology

    • Radiative Transfer Modeling: piSOFIT uses a neural-network-based MODTRAN emulator derived from 6S to model the interaction of solar radiation with the atmosphere and Earth’s surface.

    • Optimal Estimation Inversion: The workflow iteratively adjusts atmospheric parameters (e.g., water vapor, aerosols) and surface reflectance to minimize residuals between observed at-sensor radiance and modeled radiance using a Levenberg-Marquardt optimization approach.

    • Bayesian Priors & Uncertainty Quantification: Prior information about atmospheric and surface conditions is incorporated into the inversion, providing improved retrieval stability and per-pixel uncertainty estimates.

    • Superpixel Segmentation & Empirical Refinement: piSOFIT segments images into spectrally similar superpixels, solves atmospheric parameters at the superpixel level, and applies an empirical line adjustment to refine surface reflectance for each pixel.

    For more technical details, visit the Isofit documentation.

    See more
  • Requesting a Custom Bandset

    If your project requires a unique combination of spectral bands that isn't covered by our Default Firefly bandsets, you can request a custom bandset tailored to your needs.

    How to Request

    To get started, simply reach out to your Customer Success Manager (CSM) or contact us at support@pixxel.space with the following information:

    • A brief description of your use case

    • Any specific bands or wavelengths you’re looking to include (if known)

    • Why the standard bandsets don’t meet your needs

    Our team will review your request and guide you through the next steps.

    Note

    Custom bandset availability may be subject to technical constraints. We’ll work with you to find the best solution for your goals.

    See more
  • File naming convention for Pixxel Imagery

    All files in the delivery follow a consistent naming pattern:

    XXnn_imageID_YYYYMMDD_LnX_YYYYMMDD_aaabbccc.<filetype>

     

    Where:

    • XXnn: Satellite identifier (e.g., FF01 for Firefly 1)
    • imageID: Unique six-digit image identifier.
    • YYYYMMDD: Acquisition date (first instance) and product creation date (second instance).
    • LnX: Processing level (e.g. L1C, L2A)
    • aaa: Average spatial resolution
    • bb: Product version
    • ccc: Number of spectral bands in the delivered image.
    • filetype: File (e.g., .tif, .mask.tif, .geojson, .jpeg, .hdr, .xml).
    See more
  • Pixxel Imagery Overview

    Product Bundles:

    1. L2A : Bottom of Atmosphere (BOA) reflectance (default option unless otherwise specified)
    2. L1C : Top of Atmosphere (TOA) reflectance (available on request)
    3. L1B : Top of Atmosphere (TOA) radiance (available on request)

    Product Processing:

    Name DescriptionProduct Level
    Bottom of Atmosphere (BOA) reflectance

    This is radiometric, geometric, and atmospheric (aerosol and watervapor) corrected BOA reflectance data. The image is orthorectified and projected to WGS84 projection. The data is available in a geoTIFF file format (accompanied by additional metadata).

    The pixel reflectance values are linearly scaled between 0 - 50000.Thus to convert the image to 0-1 reflectance range, all the pixel values must be divided by 50000

    		L2A
    Top of Atmosphere (TOA) reflectance

    This is radiometric, and geometric corrected TOA reflectance data.The image is orthorectified and projected to WGS84 projection. The data is available in a geoTIFF file format (accompanied by additional metadata).

    The pixel reflectance values are linearly scaled between 0 - 50000. Thus to convert the image to 0-1 reflectance range, all the pixel values must be divided by 50000.

    		L1C (available on request)
    Top of Atmosphere (TOA) radiance

    This is radiometric, and geometrically corrected TOA radiance (also. termed at-sensor radiance) data. The image is orthorectified using a customer-requested projection. The data is available in a geoTIFF file format (accompanied by additional metadata). This level may be available on request.

    The pixel values are not scaled and the values have radiance units -W⋅m-2⋅sr-1⋅μm-1

    		L1B (available on request)

     

    Image Delivery Package:

    Pixxel imagery products are delivered as a structured set of files. Each product delivery includes:

    • Primary Image Files: GeoTIFF containing the capture area at the specified processing level.

    • Quality Mask File: GeoTIFF mask identifying cloud, cloud shadow, water, and other quality flags at

      bit-encoded layers.

    • Footprint Polygon: GeoJSON file representing the exact acquisition footprint.

    • Bounding Box Polygon: GeoJSON file providing the rectangular bounding extent of the acquisition.

    • ENVI Header File: .hdr file providing band, wavelength, and projection information for direct hyperspectral processing.

    • Thumbnail Preview: RGB JPEG quicklook for rapid scene visualization.

    • ReadMe File: A text document describing package contents, filename conventions, quality mask bit

      definitions, and processing notes

    See more