Glossary

From Audacity Development Manual
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This page gives very brief explanations of these terms, with some links to Wikipedia for much more comprehensive explanations.

We need a standard way of indicating that a word referred to in a definition can itself be found in the Glossary. I suggest bold italics Agreed. see Consistency

Even after 1.4.0 if needs be, we must also have an Index. And when we do, I think these terms are part of it (because of the overlap between the Index to our pages and the Glossary items). -Gale


I was hoping to get it so that clicking on Wikipedia1.png would take you to the relevant wikipedia page. This is just an idea. Happy to see other formats tried on other parts of the table, and then we pick whatever we like best -James. I know of no way on a Wiki where you can click on an image and do other than go to the image. This is the big problem with the "Audacity for the Impatient" image. I can get rid of the pointed arrow, but won't the export saddle us with the [1], [2] anyway? If it does not do so, then are we fussed about having external links looking different to links internal to this Wiki? It may be easier to color the Wiki links as #339966 which is a color associated with Wikipedia. Gale

General Terms

Link Term Description
  Audacity Project Format (.aup):
  Audio CDs:
Wikipedia1.png[1] Amplitude:
Cepstrum:
Wikipedia1.png
Some description here. It's kinda like a logarithm of a Fourier transform. Gotta getta better description [2]
Compressed Audio Format:


  • Compression:
  • Cycle:
  • Data CDs:
  • dB: (decibels) A logarithmic unit (typically of sound pressure) describing the ratio of that unit to a reference level.
  • Dynamic Range:
  • FFT: (Fast Fourier Transform). A method for performing Fourier transforms (see below) quickly.
  • Filter: A sound effect that lets some frequencies through and suppresses others.
  • Fourier Transform: A method for converting a waveform to a spectrum, and back.
  • Frequency: Audio frequency determines the pitch of a sound. Measured in Hz (see below), higher frequencies have higher pitch.
  • Harmonics: Most sounds are made up of a mix of different frequencies. In musical sounds, the component frequencies are simple multiples of each other, for example 100Hz, 200Hz, 300Hz. These are called harmonics of the lowest frequency sound.
  • High Pass Filter: A filter that lets high frequencies through.
  • Hz (Hertz): Measures a frequency event in number of cycles per second. See Frequency and Sample Rate, both of which are measured in Hz.
  • LAME:
  • Linear:
  • Logarithmic:
  • Lossless:
  • Lossy:
  • Low Pass Filter: A filter that lets low (bass) frequencies through.
  • MP3 CDs:
  • Pitch:
  • RMS:
  • Sample Rate: Measured in Hz like Frequency, this represents the number of digital samples captured per second in order to represent the waveform.
  • Spectrum: Presentation of a sound in terms of its component frequencies.
  • Uncompressed Audio Format:
  • Waveform:
  • Wavelength:

Audio File Formats

Unsure if a separate section is a good idea given I think we need entries for lossy/lossless and uncompressed / compressed audio format in the main glossary (e.g. to explain difference between audio signal and audio file compression). A lot depends if we have Audio File Formats as one page as an appendix. Play it by ear but I don't think this table has quite enough detail for each format at the moment, even with a Wikipedia link.- Gale
Term Description
Wikipedia1.png
FLAC: An Open Source lossless compressed audio format [3]
Wikipedia1.png
MIDI: A format for audio which represents individual notes. Usually MIDI audio files are captured from a keyboard instrument as pitch and duration of keys pressed, rather than being captured from the sound. [4]
Wikipedia1.png
MP2: A compressed audio format [5]
Wikipedia1.png
MP3: A compressed audio format [6]
Wikipedia1.png
Ogg Vorbis: An Open Source compressed audio format [7]
Wikipedia1.png
WAV: An uncompressed audio format [8]