ft8ts

KO | EN

gitlite — search

#javascript #react #ai #llm #golang #android #deep-learning #nodejs #windows #awesome #awesome-list #pytorch #security #open-source

(★ 15)

FT8 encoder and decoder in pure TypeScript

ft8ts Latest Version Download

Download Latest Version (.zip)

// repository documentation

Was this content helpful?

★ 0 (0 ratings)

# ft8ts

[![Tests](https://github.com/e04/ft8ts/actions/workflows/test.yml/badge.svg)](https://github.com/e04/ft8ts/actions/workflows/test.yml)

FT8/FT4 encoder and decoder in pure TypeScript. A port of the Fortran implementation from [WSJT-X](https://wsjt.sourceforge.io/wsjtx.html) v2.7.0.

## Overview

FT8/FT4 are digital amateur radio modes designed for weak-signal communication, developed by Joe Taylor (K1JT) and Steve Franke (K9AN).

This library provides pure TypeScript implementations of both encoding and decoding for FT8/FT4, suitable for use in Node.js or the browser.

## Demo

### Browser

https://e04.github.io/ft8ts/example/browser/index.html

### CLI

```bash
# Decode WAV file (FT8 or FT4)
npx @e04/ft8ts decode foo.wav [--mode ft8|ft4] [--low 200] [--high 3000] [--depth 2]

# Encode message to WAV file
npx @e04/ft8ts encode "CQ JK1IFA PM95" [--out output.wav] [--df 1000]
```

## Benchmark

The benchmark below was compiled with reference to [Comparing PyFT8 with WSJT-x and FT8_lib](https://www.reddit.com/r/amateurradio/comments/1qt27ss/comparing_pyft8_with_wsjtx_and_ft8_lib/).

| Call a | Call b | Message | WSJT-x(default) | WSJT-x (fast) | [PyFT8](https://github.com/G1OJS/PyFT8) | [ft8_lib](https://github.com/kgoba/ft8_lib) | ft8ts (depth=4) |
| :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- |
| W1FC | F5BZB | -8 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| WM3PEN | EA6VQ | -9 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| CQ | F5RXL | IN94 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| N1JFU | EA6EE | R-07 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| A92EE | F5PSR | -14 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| K1BZM | EA3GP | -9 | ☑️ | ☑️ | ☑️ | | ☑️ |
| W0RSJ | EA3BMU | RR73 | ☑️ | ☑️ | ☑️ | | ☑️ |
| K1JT | HA0DU | KN07 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| W1DIG | SV9CVY | -14 | ☑️ | ☑️ | ☑️ | | ☑️ |
| K1JT | EA3AGB | -15 | ☑️ | ☑️ | ☑️ | | ☑️ |
| XE2X | HA2NP | RR73 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| N1PJT | HB9CQK | -10 | ☑️ | ☑️ | ☑️ | ☑️ | ☑️ |
| K1BZM | EA3CJ | JN01 | ☑️ | ☑️ | | | |
| KD2UGC | F6GCP | R-23 | ☑️ | ☑️ | | | |
| WA2FZW | DL5AXX | RR73 | ☑️ | | | | |
| N1API | HA6FQ | -23 | ☑️ | | | | ☑️ |
| N1API | F2VX | 73 | ☑️ | | | | ☑️ |
| K1JT | HA5WA | 73 | ☑️ | | | | ☑️ |
| CQ | EA2BFM | IN83 | ☑️ | | | | ☑️ |
| K1BZM | DK8NE | -10 | | | | | ☑️ |

At its maximum depth mode (Depth 4), it successfully decodes 17 messages on this sample (including 17/20 rows in the table above), outperforming both `PyFT8` (12), `FT8_lib` (8), and `WSJT-x FAST mode` (14).

## Installation

`npm i @e04/ft8ts`

## Usage

### API

```typescript
import { encodeFT8, decodeFT8, encodeFT4, decodeFT4, HashCallBook } from "@e04/ft8ts";

// Encode a message to audio samples (Float32Array)
const samples = encodeFT8("CQ JK1IFA PM95", {
  sampleRate: 12000,
  baseFrequency: 1000,
});

// Create a HashCallBook to resolve hashed callsigns.
// Reuse the same instance across multiple decode calls so that
// callsigns learned from earlier frames can resolve hashes in later ones.
const book = new HashCallBook();

// Decode audio samples to messages
const decoded = decodeFT8(samples, {
  sampleRate: 12000,
  freqLow: 200,
  freqHigh: 3000,
  depth: 2,
  hashCallBook: book,
});

for (const d of decoded) {
  console.log(`${d.freq} Hz  SNR ${d.snr} dB  ${d.msg}`);
}
```

### FT4

```typescript
import { encodeFT4, decodeFT4, HashCallBook } from "@e04/ft8ts";

// Encode FT4 message
const samples = encodeFT4("CQ JK1IFA PM95", {
  sampleRate: 12000,
  baseFrequency: 1000,
});

// Decode FT4
const book = new HashCallBook();
const decoded = decodeFT4(samples, {
  sampleRate: 12000,
  freqLow: 200,
  freqHigh: 3000,
  depth: 2,
  hashCallBook: book,
});
```

### Decode Options

| Option | Default | Description |
|--------|---------|-------------|
| `sampleRate` | 12000 | Input audio sample rate (Hz) |
| `freqLow` | 200 | Lower frequency bound (Hz) |
| `freqHigh` | 3000 | Upper frequency bound (Hz) |
| `syncMin` | 1.2 | Minimum sync threshold |
| `depth` | 2 | Decoding depth: 1=fast BP only, 2=BP+OSD, 3=deep, 4=deeper AP/OSD |
| `maxCandidates` | 300 (FT8) / 100 (FT4) | Maximum candidates to process |
| `hashCallBook` | — | `HashCallBook` instance for resolving hashed callsigns |

## Build

```bash
npm run build
```

## License

GPL-3.0

## References

- [WSJT-X](https://wsjt.sourceforge.io/wsjtx.html) — Original Fortran implementation (v2.7.0), licensed under [GPL v3](https://www.gnu.org/licenses/gpl-3.0.html)

## Related Projects

- **[PyFT8](https://github.com/G1OJS/PyFT8)** — A pure Python implementation of an FT8 encoder and decoder.

- **[ft8_lib](https://github.com/kgoba/ft8_lib)** — A lightweight C implementation of an FT8 and FT4 encoder and decoder.

- **[wsjtx_lib](https://github.com/paulh002/wsjtx_lib)** — A C++ library that wraps the original WSJT-X Fortran source code.

- **[wsjtx-lib-nodejs](https://github.com/boybook/wsjtx_lib_nodejs)** — A Node.js native C++ extension and TypeScript wrapper for `wsjtx_lib`.

- **[ft8js](https://github.com/e04/ft8js)** - My previous experimental project using WebAssembly (WASM) with ft8_lib.

ft8ts

ft8ts Latest Version Download

Today's picks

Was this content helpful?

Recent Feedback

ft8ts

ft8ts Latest Version Download

Today's picks

Was this content helpful?

Recent Feedback

Download README