Delphi implementation
The Delphi implementation is the reference implementation of the Open
Streaming Format: a complete read and write path for OSF4 and OSF5, a set of
demos, and the osftool command line. It also produces the set of
reference files the other
implementations are checked against. Built with RAD Studio 23.0 (Delphi 12).
Library
The library units live under implementations/delphi/src/. The most
important public building blocks:
| Unit | Contents |
|---|---|
OSF.Types | Data and channel types (TOSFDataType, TOSFVersion, TOSFGpsLocation) and helper functions |
OSF.Filer | TOSFFile — streaming reader/writer for OSF4 and OSF5; transparent OSFZ decompression; OSF4 XML parsing via OmniXML (no MSXML dependency) |
OSF.Data.Manager | TOSFDataManager — high-level read, populates typed channels; access by name |
OSF.Data.Channels | typed in-memory channels incl. equidistant segments (each bcStartData opens a segment) |
OSF.Log | process-wide logging/progress dispatcher (Logger: TOSFLog) with a listener pattern (DECISIONS §22) |
OSF.Export.CSV / OSF.Export.CSV.Unified | CSV export — per channel (XY) and shared timeline respectively |
OSF.Export.HDF5 | HDF5 export (Windows; one compressed compound dataset per channel) |
OSF.Merger | TOSFMerger — merge several OSF files over a time interval into one output file |
OSF.Meta.Cache | sidecar .json cache per OSF file (time ranges, sample counts) for fast metadata |
A no-form program OSFCompileCheck.dpr in the implementation root covers
every library unit via uses and gives a clean compile signal after
refactorings.
Logging architecture
Every library unit writes log and progress events to the global
Logger: TOSFLog. Applications register a TLoggerListener (with its own
MinLevel and event callbacks); the singleton handles the fan-out. Details
in DECISIONS §22.
Demos
Under implementations/delphi/demos/:
| Demo | Purpose |
|---|---|
osfviewer/ | load an OSF file, list channels, render one channel as a TeeChart (IDE only) |
osfgenerator/ | writes the 17-file reference set; the console variant OSFGeneratorCLI produces it non-interactively |
osfcsvexport/ | pipeline demo TOSFFile → TOSFDataManager → CSV export |
osfmerger/ | VCL front-end for TOSFMerger (Win64) |
Command line: osftool
osftool is the verb-based command-line tool of the Delphi implementation
(Win64) with nine verbs — merge, export, info, channels, stat,
cache, config, convert, verify.
The full description is in its own chapter osftool.
Building
The library and most demos are compiled with dcc32 (Win32) or dcc64
(Win64) from the respective project directory — osfmerger and osftool
as Win64. Example (compile check):
cd implementations\delphi
dcc32 -B -Q OSFCompileCheck.dpr
The HDF5 export needs hdf5.dll at runtime; the binding (src/hdf5/) is a
standalone, OSF-independent Delphi binding to the HDF5 C library.
Source code and further reading
- Source code on GitHub: github.com/optimeas/osf,
directory
implementations/delphi/ - Command line: chapter osftool
- Format specification: chapter OSF format
This document is licensed under CC BY 4.0. Attribution: optiMEAS GmbH and optiMEAS Switzerland GmbH.