Tone
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{{Template:FuncDef|Tone(float ''length'', float ''frequency'', int ''samplerate'', int ''channels'', string ''type'', float ''level'')}} | {{Template:FuncDef|Tone(float ''length'', float ''frequency'', int ''samplerate'', int ''channels'', string ''type'', float ''level'')}} | ||
| − | This will generate sound at a given ''frequency'' for a given ''length'' of time in seconds. | + | This will generate sound at a given ''frequency'' for a given ''length'' of time in seconds. |
| + | |||
| + | ;length | ||
| + | :Length of time in seconds. Default = 10.0. | ||
| + | ;frequency | ||
| + | : Tone frequency. Default = 440. | ||
| + | ;samplerate | ||
| + | : Audio sample rate. Default = 48000. | ||
| + | ;channels | ||
| + | : Number of audio channels. Default = 2. | ||
| + | ;type | ||
| + | : "Silence", "Sine", "Noise", "Square", "Triangle" or "Sawtooth". Default = "Sine". | ||
| + | ;level | ||
| + | : The amplitude of the waveform. Default = maximum = 1.0. | ||
| − | |||
{| border=1 cellspacing=0 cellpadding=5 | {| border=1 cellspacing=0 cellpadding=5 | ||
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| Tone(frequency=2, samplerate=48000, channels=2, type="sine", level=0.4) | | Tone(frequency=2, samplerate=48000, channels=2, type="sine", level=0.4) | ||
|} | |} | ||
| − | |||
In the figure above, a sinus is generated (on a gray clip with framerate 24 fps). The period of the waveform (in frames) is the framerate divided by ''frequency'' (or fps/freq, which is 24/2=12 frames in our example). The part of the graph which is light-green represents all samples of the frame under consideration (which is frame 1 here). The number of samples in a particular frame is given by the ''samplerate'' divided by the framerate (which is 48000/24 = 2000 samples in our example). (Note that the bars are made with [[Histogram]] and the graph with the AudioGraph plugin.) | In the figure above, a sinus is generated (on a gray clip with framerate 24 fps). The period of the waveform (in frames) is the framerate divided by ''frequency'' (or fps/freq, which is 24/2=12 frames in our example). The part of the graph which is light-green represents all samples of the frame under consideration (which is frame 1 here). The number of samples in a particular frame is given by the ''samplerate'' divided by the framerate (which is 48000/24 = 2000 samples in our example). (Note that the bars are made with [[Histogram]] and the graph with the AudioGraph plugin.) | ||
Revision as of 20:45, 7 November 2014
Tone(float length, float frequency, int samplerate, int channels, string type, float level)
This will generate sound at a given frequency for a given length of time in seconds.
- length
- Length of time in seconds. Default = 10.0.
- frequency
- Tone frequency. Default = 440.
- samplerate
- Audio sample rate. Default = 48000.
- channels
- Number of audio channels. Default = 2.
- type
- "Silence", "Sine", "Noise", "Square", "Triangle" or "Sawtooth". Default = "Sine".
- level
- The amplitude of the waveform. Default = maximum = 1.0.
|
| Tone(frequency=2, samplerate=48000, channels=2, type="sine", level=0.4) |
In the figure above, a sinus is generated (on a gray clip with framerate 24 fps). The period of the waveform (in frames) is the framerate divided by frequency (or fps/freq, which is 24/2=12 frames in our example). The part of the graph which is light-green represents all samples of the frame under consideration (which is frame 1 here). The number of samples in a particular frame is given by the samplerate divided by the framerate (which is 48000/24 = 2000 samples in our example). (Note that the bars are made with Histogram and the graph with the AudioGraph plugin.)
More generally, the waveform above is described by
g(n,s) = level * sin(2*pi*(frequency*n/framerate + s*frequency/samplerate))
with "n" the frame and "s" the sample under consideration (note that s runs from 0 to samplerate/framerate - 1).
In the example above, this reduces to
g(n,s) = 0.4 * sin(2*pi*(2*n/24 + s*2/48000))
with "n" the frame and "s" the sample under consideration (note that s runs from 0 to 1999).
Changes:
| v2.56 | Added Level in v2.56. |
| v2.54 | Initial Release. |
