HighDeF is a native document-based HDF5 viewer for Apple devices. The focus is on preview of large timeseries datasets. Limited image display capability exists.
HDF5 is vendored as a git submodule at Vendor/hdf5 and pinned to the 2.1.0 release tag. Build it into an XCFramework before building the app using Scripts/build-hdf5-xcframework.sh; this produces Vendor/Build/HDF5.xcframework. Then you can build the app with xcode or the build script.
- Opening a document calls
H5Fopenand keeps only the file handle plus lightweight metadata in memory. - Expanding a group calls
H5Literate2for that group only; the tree is not recursively loaded. - Selecting an object loads its attributes with an 8 KB value preview limit.
- Dataset previews use an HDF5 hyperslab at the origin, capped by row and column limits. Large datasets are not loaded wholesale.
- The dataset table requests bounded row windows as rows become visible instead of reading the full dataset.
- Numeric plots are rendered from a bounded preview sample: one-dimensional and two-column samples become line plots, wider numeric slices become heatmaps.
- Soft and external links are represented as links instead of being traversed automatically.
The macOS app keeps the HDF5 file open through an NSDocument; the iOS app opens documents through a UIDocumentBrowserViewController. Both ports share a SwiftUI sidebar-adaptable document viewer, the same HDF5 access layer, lazy hierarchy rendering, bounded dataset previews, and sampled numeric plots.