BigTIFF

BigTIFF is a variant of the TIFF (Tagged Image File Format) designed to store very large raster images and datasets. It addresses the 4-gigabyte size limit of classic TIFF by extending the addressing scheme to 64-bit offsets for image data and for the Image File Directories (IFDs). In BigTIFF, IFDs, their entries, and the blocks they reference can use 64-bit values, enabling file sizes that can reach into the terabytes on capable systems.

The format preserves the overall TIFF data model, including tag-based metadata and common compression schemes, while updating the header and IFD entries to accommodate 64-bit counts and offsets. This compatibility-within-TIFF approach allows many existing TIFF tools to read or adapt to BigTIFF, provided they implement the extended offsets and IFD structures.

Usage and adoption: BigTIFF is widely supported by major image processing and geospatial libraries, such as libtiff, GDAL, and ImageMagick, and is commonly employed in domains that generate very large raster datasets, including satellite imagery, aerial photography, geographic information systems, remote sensing, microscopy, and some medical imaging workflows. In geospatial contexts, GeoTIFF files can be stored as BigTIFF to handle high-resolution, expansive datasets.

Limitations and considerations: not all software that can read classic TIFF automatically handles BigTIFF reads; some pipelines require explicit support or conversion. Because BigTIFF introduces larger IFD entries and 64-bit offsets, there can be modest increases in file complexity and parsing requirements, though the core TIFF semantics remain intact.