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Morse Orbit

Decode

Morse code decoder: tap, audio file and image reader

Got Morse that isn't typed text? Tap it in, upload a recording or read a printed pattern. Everything is analysed on your device.

Signal input

Tap to build Morse

Tap dots and dashes, add a letter gap after each letter and a word gap between words. With the pad focused you can also use the keys . - Space / and Backspace.

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Your sequence appears here.

Coming later

Live microphone decoder

Decoding live sound needs calibration, noise handling and testing in real rooms before it can be trusted. It is not available yet. In the meantime, record the signal and use the audio file decoder.

Decoded result

Accepted results from the tools above open here.

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Signal timeline

dot · 1 unit dash · 3 unitsletter gap · 3 · word gap · 7

Your signal will appear here.

Methodology

How the experimental decoders work

Audio file decoder

  1. The recording is mixed to mono and its loudness is measured every 4 ms.
  2. A threshold between the background level and the tone level separates “on” from “off”. The sensitivity slider moves that threshold.
  3. Very short blips (under 8 ms) are treated as noise and merged.
  4. Tone lengths are grouped into short and long to estimate the dot length; the speed estimate follows from it.
  5. Each tone becomes a dot or dash and each silence an element, letter or word gap. Lengths close to a decision boundary are flagged as uncertain.

Tested on: synthetic single-tone recordings at 12–30 WPM, Farnsworth spacing, all-dash messages and added white noise. Not yet tested on: real radio audio, phone recordings, fading signals, hand-keyed timing, several signals at once or speech over Morse — expect errors there and always review the result.

Image signal reader

  1. The image is converted to black and white with an automatic threshold; light-on-dark images are detected and inverted.
  2. The most prominent horizontal band of ink is selected. Other lines are ignored with a warning.
  3. Shapes are found column by column. Wide shapes (about three times wider than tall) are dashes, round ones dots, tall thin ones slashes.
  4. Spaces between shapes are compared with the smallest space to find letter and word breaks.

Works with: one straight line of printed, high-contrast dots and dashes. Does not work with: handwriting, several lines, tilted or curved text, photos with shadows, or images containing ordinary letters. It is not OCR.

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