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 A spectrogram of violin playing with linear frequency on the vertical axis and time on the horizontal axis. The bright lines show how the spectral components change over time. The intensity coloring is logarithmic (black is −120 dBFS). The spectrogram is the result of calculating the frequency spectrum of windowed frames of a compound signal. It is a three-dimensional plot of the energy of the frequency content of a signal as it changes over time. A spectrogram of a violin waveform. ...
A spectrogram of a violin waveform. ...
dBFS means decibels full scale. It is an abbreviation for decibel amplitude levels in digital systems which have a maximum available level (like PCM encoding). ...
Familiar concepts associated with a frequency are colors, musical notes, radio/TV channels, and even the regular rotation of the earth. ...
Window functions are applied to avoid discontinuities at the beginning and the end of a set of data. ...
In information theory, a signal is the sequence of states of a communications channel that encodes a message. ...
Spectrograms are used to identify phonetic sounds, to analyse the cries of animals, and in the fields of music, sonar/radar, speech processing, etc. A spectrogram can also be called a spectral waterfall, sonogram, voiceprint, or voicegram. The instrument that generates a spectrogram is called a sonograph. Phonetics (from the Greek word φωνή, phone meaning sound or voice) is the study of the sounds of human speech. ...
For other uses, see Music (disambiguation). ...
This article is about underwater sound propagation. ...
For other uses, see Radar (disambiguation). ...
Speech processing is the study of speech signals and the processing methods of these signals. ...
Format
A spectrogram of an FM signal. In the most usual format, the horizontal axis represents time, the vertical axis is frequency, and the intensity of each point in the image represents amplitude of a particular frequency at a particular time. Often the diagram is reduced to two dimensions by indicating the intensity with thicker lines, more intense colors or grey values. This article is about the concept of time. ...
For other uses, see Frequency (disambiguation). ...
Intensity is a widely-used term, which can mean: In colloquial use: Strength Amplitude Level In physics: Intensity, power per unit area (W/m2) Field strength of electric, magnetic, or electromagnetic fields. ...
There are many variations of format. Sometimes the vertical and horizontal axes are switched, so time runs up and down. Sometimes the amplitude is represented as the height of a 3D surface instead of color or intensity. The frequency and amplitude axes can be either linear or logarithmic, depending on what the graph is being used for. For instance, audio would usually be represented with a logarithmic amplitude axis (probably in dB), and frequency would be linear to emphasize harmonic relationships, or logarithmic to emphasize musical, tonal relationships. For other uses, see Linear (disambiguation). ...
Look up logarithm in Wiktionary, the free dictionary. ...
The decibel is a dimensionless unit (like percent) that is a measure of ratios on a logarithmic scale. ...
Generation
 Spectrogram of a male voice saying "tatata"
 Spectrogram of a Japanese woman saying "minato" Spectrograms are usually created in one of two ways; either with a series of bandpass filters, or calculated from the time signal using the short-time Fourier transform (STFT). An example spectrogram (sonogram) made in the freeware program Praat. ...
An example spectrogram (sonogram) made in the freeware program Praat. ...
Image File history File links Download high resolution version (1800x1125, 131 KB) Spectrogram [minato].png info spectrograph of the Tokyo Japanese word [minato] generated with Praat from an . ...
Image File history File links Download high resolution version (1800x1125, 131 KB) Spectrogram [minato].png info spectrograph of the Tokyo Japanese word [minato] generated with Praat from an . ...
The frequency axis of this symbolic diagram would be logarithmically scaled. ...
The short-time Fourier transform (STFT), or short-term Fourier transform, is a Fourier-related transform used to determine the sinusoidal frequency and phase content of a signal as it changes over time. ...
The filter method is usually used in the analog, continuous version of measurement. The frequency range of the signal (an audio signal, for instance, would have frequencies in the range of 20 Hz - 20 kHz) is divided into equal sections, either linearly (0-100, 100-200, 200-300, ...), or logarithmically (10-100, 100-1000, 1000-10000, ...). The signal is input to a corresponding filter, which removes most of the signal that does not fall within its frequency band (imperfect window functions and limited frequency resolution will cause some "bleeding" between adjacent frequency bands). The magnitudes of each filter's output are recorded as functions of time. Each recording then corresponds to a horizontal line in the image; a measurement of magnitude versus time for a specific frequency band. An analog or analogue signal is any continuously variable signal. ...
An audio filter is a type of filter used for processing sound signals. ...
In signal processing, a window function (or apodization function) is a function that is zero-valued outside of some chosen interval. ...
To calculate the spectrogram using the magnitude of the STFT is usually a digital process. Digitally sampled data, in the time domain, is broken up into chunks, which usually overlap, and Fourier transformed to calculate the magnitude of the frequency spectrum for each chunk. Each chunk then corresponds to a vertical line in the image; a measurement of magnitude versus frequency for a specific moment in time. This article is being considered for deletion in accordance with Wikipedias deletion policy. ...
A sample refers to a value or set of values at a point in time and/or space. ...
The spectrums or time plots are then "laid side by side" to form the image or a three-dimensional surface.
The spectrogram is given by the magnitude of the STFT of the function: The magnitude of a mathematical object is its size: a property by which it can be larger or smaller than other objects of the same kind; in technical terms, an ordering of the class of objects to which it belongs. ...
Creating sound from a spectrogram The above process can be reversed; some programs are available that turn a digital image into sound: A computer program is a collection of instructions that describe a task, or set of tasks, to be carried out by a computer. ...
 A spectrograph of the white noise at the end of the leaked version of "My Violent Heart," from Nine Inch Nails' Year Zero This technique allows electronic music artists to "hide" images in their music. Examples include: The first Macintosh computer, introduced in 1984, upgraded to a 512K Fat Mac. The Macintosh or Mac, is a line of personal computers designed, developed, manufactured, and marketed by Apple Computer. ...
Windows redirects here. ...
This article is about operating systems that use the Linux kernel. ...
A cross-platform (or platform independent) programming language, software application or hardware device works on more than one system platform (e. ...
Java language redirects here. ...
FL Studio (formerly Fruity Loops) is a digital audio workstation, developed by Belgian company Image-Line Software. ...
Aphex Twin (born Richard David James on August 18, 1971 in Limerick, Ireland) is a Cornish electronic music artist, credited with pushing forward the genres of techno, ambient, acid and drum and bass. ...
Alternate cover [[Image:|200px|CD2 (WAP105CDR)|200px]] CD2 (WAP105CDR) Windowlicker is a 1999 single by electronic music artist Richard D. James, released under the Aphex Twin name on Warp. ...
NIN redirects here. ...
Year Zero (also known as Halo 24) is the sixth Nine Inch Nails studio album, released on April 16, 2007 in Europe, April 17 in the United States, and April 25, 2007 in Japan. ...
For other uses, see Electronic music (disambiguation). ...
- Aphex Twin hid an image of himself in a spectrogram. The image can be found on Track 2 of the Windowlicker EP as a nine-second sweeping section right at the end. (It is recognizable in an MP3, but the compression changes the spectrogram and it is not as clear as from the CD.) Aphex Twin also hid the image of a spiral shape in his first track from the "Windowlicker" EP. [1]
- The song "Look" from Venetian Snares' album Songs About My Cats, contains several images of his cats.
- The song "3recurring" from Plaid on their album Rest Proof Clockwork contains the recurring 3s represented as a logo on the cover of the "Not for Threes" album.
- Nine Inch Nails has employed this technique on a few occasions as part of an ongoing Alternate Reality Game for their album Year Zero.
- The MP3 version of "My Violent Heart" (deliberately leaked before Year Zero was released) contains a few brief moments of static at the end. When analyzed in a spectrogram, it reveals the image of a hand reaching down from the sky. This image echoes a similar theme seen throughout the alternate reality game viral marketing campaign launched for the album. On the official version of the album, the sound appears at the end of the song "The Warning."
- Another new Nine Inch Nails track from Year Zero was also found on a flash drive in a bathroom stall on their current European tour. This time it was "Me, I'm Not." Along with the song, was an MP3 of "cricket chirping", which when put through a spectrogram revealed the number: 216.333.1810.
- Using this method again to deliver clues as part of the Year Zero ARG, there were two extra audio files included in the Garageband Multitrack files for the song Capital G. The images in the sounds are of various avatars of user at the Nine Inch Nails oriented forum Echoing the Sound. The user names are used to form the title of a new site that is part of the ARG.
On spectrograms of the records of Mike Oldfield's song "Tubular Bells" signals from the Rugby VLF transmitter are found[citation needed]. Aphex Twin (born Richard David James on August 18, 1971 in Limerick, Ireland) is a Cornish electronic music artist, credited with pushing forward the genres of techno, ambient, acid and drum and bass. ...
Alternate cover [[Image:|200px|CD2 (WAP105CDR)|200px]] CD2 (WAP105CDR) Windowlicker is a 1999 single by electronic music artist Richard D. James, released under the Aphex Twin name on Warp. ...
For other uses, see MP3 (disambiguation). ...
Alternate cover [[Image:|200px|CD2 (WAP105CDR)|200px]] CD2 (WAP105CDR) Windowlicker is a 1999 single by electronic music artist Richard D. James, released under the Aphex Twin name on Warp. ...
Venetian Snares is the primary performing alias of Canadian electronic musician Aaron Funk (born January 11, 1975). ...
Songs About My Cats is a 2001 IDM album by Venetian Snares. ...
The word plaid has varying but related meanings in the Goidelic languages and is used to refer to: Plaid (pattern), a cross-hatched dyeing pattern often used for wool clothing and distinctly Gaelic Plaid, Plaid Cymru, the largest political party advocating independence for Wales Plaid (band), an English electronic music...
Rest Proof Clockwork was Plaids second album released after leaving The Black Dog. ...
NIN redirects here. ...
Alternate Reality, see Alternate Reality (computer game). ...
Year Zero (also known as Halo 24) is the sixth Nine Inch Nails studio album, released on April 16, 2007 in Europe, April 17 in the United States, and April 25, 2007 in Japan. ...
Year Zero (also known as Halo 24) is the sixth Nine Inch Nails studio album, released on April 16, 2007 in Europe, April 17 in the United States, and April 25, 2007 in Japan. ...
In the Year Zero alternate reality game several characters and organizations are mentioned. ...
Alternate Reality, see Alternate Reality (computer game). ...
Viral marketing and viral advertising refer to marketing techniques that use pre-existing social networks to produce increases in brand awareness, through self-replicating viral processes, analogous to the spread of pathological and computer viruses. ...
Year Zero (also known as Halo 24) is the sixth Nine Inch Nails studio album, released on April 16, 2007 in Europe, April 17 in the United States, and April 25, 2007 in Japan. ...
Year Zero (also known as Halo 24) is the sixth Nine Inch Nails studio album, released on April 16, 2007 in Europe, April 17 in the United States, and April 25, 2007 in Japan. ...
Alternate Reality, see Alternate Reality (computer game). ...
GarageBand is a software application that allows users to create music or podcasts. ...
NIN redirects here. ...
Michael Gordon Oldfield (born May 15, 1953 in Reading, England) is a multi-instrumentalist musician and composer, working a style that blends progressive rock, folk, ethnic or world music, classical music, electronic music and more recently dance. ...
This article is about the Mike Oldfield album. ...
A view of the tallest masts ( alternative view) The Rugby VLF transmitter is a large VLF transmission facility near the town of Rugby, Warwickshire in England. ...
Some modern music is also created using spectrograms as an intermediate medium; changing the intensity of different frequencies over time, or even creating new ones, by drawing them and then inverse transforming. See Audio timescale-pitch modification and Phase vocoder. Time stretching is the process of changing the speed or duration of an audio signal without affecting its pitch. ...
The phase vocoder is a type of vocoder which preserves both frequency and phase information. ...
VLF-reception with the PC Using spectrograms generated by audio-band FFT-software is a very convenient way to receive frequencies below 24 kHz. This technique allows wide-range reception of the VLF-range. Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 to 30 kHz. ...
See also The Fast Fourier Transform (FFT) is an efficient algorithm to compute the discrete Fourier transform (DFT) and its inverse. ...
The short-time Fourier transform (STFT), or short-term Fourier transform, is a Fourier-related transform used to determine the sinusoidal frequency and phase content of a signal as it changes over time. ...
Spectrometer A spectrometer is an optical instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. ...
This article deals with the general meaning of spectrum and the history of its use. ...
The wavelet transform is a transformation to basis functions that are localized in scale and in time as well (where the Fourier transform is only localized in frequency, never giving any information about where in space or time the frequency happens). ...
A time-frequency representation (TFR) is a view of a signal (taken to be a function of time) represented over both time and frequency. ...
External links Look up Spectrogram in Wiktionary, the free dictionary. Wiktionary (a portmanteau of wiki and dictionary) is a multilingual, Web-based project to create a free content dictionary, available in over 151 languages. ...
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