Sanitize NowPlaying

Current release: v3.0.4

Standalone Windows application that monitors playout metadata and turns it into clean, predictable RDS RadioText (RT), RT+ and separate component files for Stereo Tool, Magic RDS 4 and other file-based RDS workflows.

Sanitize NowPlaying v3.0.0 was the direct successor to v2.1.8, the final PowerShell/conhost release. v3 is a complete C# / .NET Framework 4.8 WinForms rewrite. v3.0.4 keeps the established settings and six-file output contract while adding focused sanitizer correctness, regex-safety and metadata-preservation hardening on top of the v3.0.3 responsiveness/UI refinements.

Designed for small and semi-professional FM stations that want broadcast-ready RDS metadata without manually retagging an entire music library.

This project was created through iterative co-development with ChatGPT 5.2 / 5.5 / 5.6, combining AI-assisted development with hands-on design, testing and optimization.

What's new in v3.0.4

• Prevents version/remaster/whitelist/soundtrack/live-location cleanup from consuming meaningful title text before the rightmost eligible metadata tail
• Preserves natural hyphenated text such as Re-Live It, Non-Studio Jam, Squeaky-Clean and Hero-Epic Movie Soundtrack
• Makes country cleanup more preservation-first: ambiguous ISO-like prefixes such as DJ, MC, TV and CAN are preserved, while clear full-country prefixes and safe artist-only trailing ISO2 tags such as Diesel (NL) remain supported
• Supports clear country-prefix forms even when a feed omits whitespace around the separator, including The Netherlands-Walk Along
• Uses single-pass HTML entity decoding, strips decoded invisible controls, normalizes NFD input to NFC and keeps apostrophe-case cleanup consistent across standalone, RT and RT+ output
• Tightens degree/temperature and omega/unit replacement boundaries and preserves natural compilation phrases such as Best of Friends, Best of Both Worlds and The Best of Both Worlds
• Moves regex timeout configuration to process start, uses bounded matching in higher-risk sanitizer paths and fails closed on RegexMatchTimeoutException
• Reduces the Core raw-metadata limit from 4096 to 1024 characters; the 64 KiB input-file guard is unchanged
• Expands the processing-engine self-test suite from 73 to 158 tests
• Settings schema, input/output filenames, delimiter behaviour and RT+ target formats are unchanged from v3.0.3; no migration is required

v3.0.0 rewrite highlights

• Standalone WinForms application for Windows 10 and Windows 11
• No PowerShell, console host or Windows Terminal required at runtime
• First-run Working Directory setup with integrated folder and volume picker
• Configurable input filename; nowplaying.txt remains the default
• Low-overhead hybrid input monitoring with immediate wake-up on metadata changes
• Automatic handling of temporarily unavailable mapped drives and UNC Working Directories
• Clear EMPTY, MISSING, EXPIRED, OFFLINE / unavailable and INVALID DATA states
• Transactional in-app F10 Settings UI with draggable nested overlays
• Atomic settings saves and verified single-worker runtime handover
• Per-file atomic output writes with retry protection
• Startup freshness checks and confirmed output clearing on shutdown to prevent stale RDS data
• Single-instance protection
• In-app About panel and polished graphical status presentation

Metadata processing

• Intelligent artist/title cleanup for encoders, bitrates, country/year suffixes, platform tags, duplicate information and other common library noise
• Preservation-first handling for ambiguous country codes, natural hyphenation and technical/version tails
• Conservative artist/title splitting
• Balanced bracket handling for (), [] and {}, including cleanup of unmatched or mismatched brackets
• Configurable artist/title order for compact RT/RT+ presentation
• Multilingual or custom prefix text
• Configurable connector text
• Configurable playout delimiter, including U+241F, TAB and custom values
• Optional Greek/Cyrillic transliteration and ASCII-safe mode
• Independent 64-character artist/title component limits
• Adaptive trimming of combined RT/RT+ content to the RDS 64-character limit
• Short 100 ms partial-write guard for empty-title / artist-only input, with later file changes reprocessed normally

Output files

All output files are written as UTF-8 without BOM in the selected Working Directory and are replaced atomically.

File	Contents
prefix.txt	Selected multilingual prefix or custom prefix text, or empty
artist.txt	Sanitized artist, independently limited to 64 characters, or empty
connector.txt	Configured connector when both artist and title are present, or empty
title.txt	Sanitized title, independently limited to 64 characters, or empty
nowplaying_rt.txt	Compact combined RadioText in the configured artist/title order, or empty
nowplaying_rtplus.txt	Compact RT+ output in the selected target syntax, or empty

For nowplaying_rtplus.txt, Stereo Tool is the backward-compatible default. Magic RDS 4 can be selected as an alternative RT+ output target.

The component files keep fixed semantic identities: artist.txt always contains the artist, connector.txt the connector and title.txt the title. The Artist/title order setting changes presentation order, not file identity.

Requirements

• Windows 10 or Windows 11
• .NET Framework 4.8

The application is built as AnyCPU.

Sanitize-NowPlaying.settings.json is stored next to SanitizeNowPlaying.exe, so run the application from a directory in which the current user has write permission.

Quick start

1. Download the current Sanitize-NowPlaying.zip.
2. Extract it to a writable folder.
3. Run SanitizeNowPlaying.exe.
4. On first start, select the Working Directory used by your playout software.
5. Configure the playout application to write artist/title metadata to the selected input file. The default filename is nowplaying.txt.
6. Open F10 Settings when you want to change the Working Directory, input filename, prefix, artist/title order, connector, ASCII/transliteration behaviour, delimiter or RT+ output target.
7. Configure Stereo Tool, Magic RDS 4 or another RDS application to read the ready-made RT/RT+ file or the separate component files required by your workflow.

When using the recommended U+241F separator, a typical playout metadata format is:

%artist␟%title

Stereo Tool component example

The separate component files can be combined as an alternating RadioText sequence in Stereo Tool. For example:

5s:\r"C:\RDS\prefix.txt"/10s:\+AR\r"C:\RDS\artist.txt"\-/5s:\r"C:\RDS\connector.txt"/10s:\+TI\r"C:\RDS\title.txt"\-

This displays the prefix for 5 seconds, the artist for 10 seconds with an RT+ artist tag, the connector for 5 seconds, and the title for 10 seconds with an RT+ title tag.

Synchronization note: Stereo Tool reads each referenced component file when that section becomes active rather than taking one shared snapshot of all component files. If metadata changes mid-sequence, components from adjacent songs can therefore be mixed. Use the ready-made nowplaying_rt.txt / nowplaying_rtplus.txt output when guaranteed artist/title consistency is more important than separate component rotation.

Release lineage

v3.0.0 established the C# / WinForms generation as a continuation of the existing project rather than a separate product. v3.0.1 added conservative metadata-preservation hardening. v3.0.2 strengthened malformed-input handling, decoding, RT+ escaping, worker recovery and diagnostics. v3.0.3 reduced the artist-only quiet period and refined status/contrast presentation. v3.0.4 adds focused sanitizer correctness, Unicode/entity consistency and regex-safety hardening while retaining the same settings schema, output filenames and file-interface contract. PowerShell/conhost v2.1.8 remains the compatibility baseline for unaffected processing cases.

For users of v2.1.8, the important continuity points are:

• existing settings schema retained;
• existing output filenames retained;
• unaffected baseline processing cases remain parity-tested against v2.1.8;
• nowplaying.txt remains the default input filename;
• Stereo Tool remains the default RT+ output target.

Sanitize NowPlaying v3 is distributed as prebuilt Windows software. The v3 source code is not publicly distributed.

License

Sanitize NowPlaying v3.0.0 and later is distributed under the proprietary Sanitize NowPlaying license included with the release package.

The v3 executable may be used for private, commercial, broadcast, educational and organizational purposes under those terms. The complete, unmodified official binary package may also be redistributed subject to the license conditions.

Legacy note: Sanitize NowPlaying v2.x was previously released under GNU GPLv3. Those historical v2.x releases remain under GPLv3; the v3 license does not revoke or alter rights already granted for them.

The v3 source code is not publicly distributed.

Verification

For v3.0.4, the release verification chain includes:

• 158 processing-engine self-tests, including v3.0.1 metadata-preservation, v3.0.2 malformed-input / RT+ hardening and v3.0.4 sanitizer-preservation / regex-safety regressions;
• 35 unaffected baseline cases × 6 output fields against the PowerShell v2.1.8 processing reference;
• 34 runtime/settings/file-I/O tests;
• 9 application-state regression tests;
• 26 settings/overlay regression tests;
• 25 picker/network/burn-in tests;
• 13 accelerated stress/soak tests;
• final v3.0.4 production application compile.

Disclaimer

Stereo Tool is a product of Thimeo Audio Technology B.V. Magic RDS 4 is a product of Pira.cz. This project is not affiliated with or endorsed by either vendor.