⚠️ Warning: This is a draft ⚠️
This means it might contain formatting issues, incorrect code, conceptual problems, or other severe issues.
If you want to help to improve and eventually enable this page, please fork RosettaGit's repository and open a merge request on GitHub.
{{draft task}} [[Category:Electronics]] [[Category:Sciences]] [[Category:Sound]] [[Category:Temporal media]] {{omit from|GUISS}} {{omit from|Lotus 123 Macro Scripting}} {{omit from|Scala}} {{omit from|TPP}}
An audio [[wp:Signal_generator|frequency generator]] produces a continual audible monotone at a set frequency and level of volume. There are controls to adjust the frequency and the volume up and down as desired. Some also have a selector to switch the waveform type between sine wave, square wave and triangular sawtooth.
The task is to emulate an audio frequency generator. It is permissible to use an inbuilt computer speaker if the system does not have the facility to utilize dedicated sound hardware.
The solution should include:
- A demonstration of how to check for availability of sound hardware on the system (on systems where this is possible)
- A demonstration of how to produce a continual audible monotone (on sound hardware this would typicvally be a sine wave)
- A method of adjusting the frequency and volume of the monotone. (one way would be to use left and right arrow keys to increase or decrease frequency, and up and down keys to increase or decrease the volume)
- A method to silence or reset the sound hardware on exit.
Optionally the solution can also include:
- A demonstration of how to fall back to internal speaker, if sound hardware is not available
- A facility to switch between sine wave, square wave and triangular sawtooth
Languages that provide no facilities for utilizing sound hardware of any kind should be omitted.
Axe
{{untested|Axe}}
ClrHome
Disp "FREQ:",i
10→F
Repeat getKey(15)
If getKey(3)
F++
F=0?-1→F
ElseIf getKey(2)
F--
F=-1?0→F
End
Output(5,0,F▶Dec)
Freq(F,10000)
End
Go
As Go does not have any audio support in its standard library, this invokes the SoX utility's 'play' command with the appropriate parameters to emulate an audio frequency generator. It appears that SoX automatically uses the internal speaker if there is no sound hardware available.
The duration of the monotone is set in advance (to a small number of seconds) and the application ends when it finishes playing. Consequently, a method to silence it is not required.
package main import ( "bufio" "fmt" "log" "os" "os/exec" "strconv" ) func check(err error) { if err != nil { log.Fatal(err) } } func main() { scanner := bufio.NewScanner(os.Stdin) freq := 0 for freq < 40 || freq > 10000 { fmt.Print("Enter frequency in Hz (40 to 10000) : ") scanner.Scan() input := scanner.Text() check(scanner.Err()) freq, _ = strconv.Atoi(input) } freqS := strconv.Itoa(freq) vol := 0 for vol < 1 || vol > 50 { fmt.Print("Enter volume in dB (1 to 50) : ") scanner.Scan() input := scanner.Text() check(scanner.Err()) vol, _ = strconv.Atoi(input) } volS := strconv.Itoa(vol) dur := 0.0 for dur < 2 || dur > 10 { fmt.Print("Enter duration in seconds (2 to 10) : ") scanner.Scan() input := scanner.Text() check(scanner.Err()) dur, _ = strconv.ParseFloat(input, 64) } durS := strconv.FormatFloat(dur, 'f', -1, 64) kind := 0 for kind < 1 || kind > 3 { fmt.Print("Enter kind (1 = Sine, 2 = Square, 3 = Sawtooth) : ") scanner.Scan() input := scanner.Text() check(scanner.Err()) kind, _ = strconv.Atoi(input) } kindS := "sine" if kind == 2 { kindS = "square" } else if kind == 3 { kindS = "sawtooth" } args := []string{"-n", "synth", durS, kindS, freqS, "vol", volS, "dB"} cmd := exec.Command("play", args...) err := cmd.Run() check(err) }
Perl
use strict 'vars'; use feature 'say'; use feature 'state'; use Audio::NoiseGen qw(play sine square triangle); use Term::ReadKey qw(ReadMode ReadLine); Audio::NoiseGen::init() || die 'No access to sound hardware?'; print "Play [S]ine, s[Q]uare or [T]riangle wave? "; my $ans_freq = uc(<>); print "Pick a volume [0-9]"; my $ans_volume = <>; say 'Volume: '. (my $volume = 0.1 + 1 * $ans_volume/10); ReadMode(3); my $waveform = $ans_freq eq 'Q' ? 'square' : $ans_freq eq 'T' ? 'triangle' : 'sine'; play ( gen => amp ( amount => $volume, gen => &$waveform( freq => setfreq(440) ) ) ); sub setfreq { state $freq; say $freq = shift; return sub { ReadMode(3); state $cnt; unless ($cnt++ % 1000) { my $key = ReadLine(-1); my $previous = $freq; if ($key eq "\e[A") { $freq += 10 } elsif ($key eq "\e[B") { $freq -= 10 } elsif ($key eq "\e[C") { $freq += 100 } elsif ($key eq "\e[D") { $freq -= 100 } say $freq if $freq != $previous; } return $freq; } }
Phix
-- demo/rosetta/Audio_frequency_generator.exw
include pGUI.e
Ihandle dlg, frequency, duration
atom k32=0, xBeep
function button_cb(Ihandle /*playbtn*/)
integer f = IupGetInt(frequency,"VALUE"),
d = IupGetInt(duration,"VALUE")
if platform()=WINDOWS then
if k32=0 then
k32 = open_dll("kernel32.dll")
xBeep = define_c_proc(k32, "Beep", {C_INT,C_INT})
end if
c_proc(xBeep,{f,d})
else
system(sprintf("play -n synth %f sine %d", {d/1000, f}))
end if
end if
return IUP_DEFAULT
end function
function valuechanged_cb(Ihandle val)
-- maintain the labels as the sliders are moved
Ihandle parent = IupGetParent(val),
lbl = IupGetNextChild(parent, NULL)
integer v = IupGetInt(val,"VALUE")
IupSetInt(lbl,"TITLE",v)
return IUP_DEFAULT
end function
procedure main()
Ihandle flabel, dlabel, frame1, frame2, playbtn
IupOpen()
flabel = IupLabel("2000","ALIGNMENT=ARIGHT,NAME=val_label,SIZE=20x8")
frequency = IupValuator("HORIZONTAL","VALUECHANGED_CB", Icallback("valuechanged_cb"),
"EXPAND=HORIZONTAL, CANFOCUS=NO, MIN=50, MAX=10000, VALUE=2000")
frame1 = IupFrame(IupHbox({flabel,frequency}),"TITLE=\"Frequency (Hz): \"")
dlabel = IupLabel("500","ALIGNMENT=ARIGHT,NAME=val_label,SIZE=20x8")
duration = IupValuator("HORIZONTAL","VALUECHANGED_CB", Icallback("valuechanged_cb"),
"EXPAND=HORIZONTAL, CANFOCUS=NO, MIN=100, MAX=3000, VALUE=500")
frame2 = IupFrame(IupHbox({dlabel,duration}),"TITLE=\"Duration (ms): \"")
playbtn = IupHbox({IupFill(),
IupButton("Play",Icallback("button_cb"),"PADDING=30x0"),
IupFill()},"MARGIN=0x20")
dlg = IupDialog(IupVbox({frame1,
frame2,
playbtn}, "MARGIN=10x5, GAP=5"))
IupSetAttribute(dlg,"TITLE","Audio Frequency Generator")
IupSetAttribute(dlg,"RASTERSIZE","500x230")
IupCloseOnEscape(dlg)
IupShow(dlg)
IupMainLoop()
IupClose()
end procedure
main()
Pure Data
'''audio-frequency-generator.pd'''
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#X floatatom 554 34 5 0 0 0 MIDI_note_number - -;
#X obj 554 52 mtof;
#X obj 32 142 phasor~;
#X obj 119 371 *~;
#X obj 227 345 line~;
#X floatatom 319 285 5 0 0 0 - - -;
#X floatatom 154 444 5 0 0 1 dB - -;
#X obj 154 423 env~ 256;
#X obj 154 462 - 100;
#X obj 320 357 vu 15 120 empty empty -1 -8 0 10 -66577 -1 1 0;
#X msg 227 323 \$1 20;
#X obj 32 292 *~;
#X obj 84 293 *~;
#X obj 120 293 *~;
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#X obj 319 165 tgl 15 0 empty empty sine 20 7 0 10 -261234 -1 -258113 0 1;
#X obj 319 188 tgl 15 0 empty empty square 20 7 0 10 -261234 -1 -258113 0 1;
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#X obj 173 142 triang~;
#X obj 172 293 *~;
#X obj 319 211 tgl 15 0 empty empty triangle 20 7 0 10 -261234 -1 -258113 0 1;
#X obj 120 142 square~;
#X obj 226 142 pulse~;
#X obj 227 293 *~;
#X obj 319 234 tgl 15 0 empty empty pulse 20 7 0 10 -261234 -1 -258113 0 1;
#X obj 32 164 -~ 0.5;
#X obj 45 462 tabwrite~ graph;
#X obj 529 193 loadbang;
#X msg 529 215 \; pd dsp 1;
#X msg 319 34 18 \, 24000 30000;
#X msg 529 250 \; pd dsp 0;
#X text 509 223 on;
#X text 503 258 off;
#X msg 32 34 50;
#X msg 63 34 100;
#X msg 94 34 200;
#X msg 126 34 500;
#X msg 157 34 1000;
#X msg 195 34 2000;
#X msg 232 34 4000;
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#X connect 48 0 3 0;
'''square~.pd'''
#N canvas 787 211 450 300 10;
#X obj 46 17 inlet;
#X obj 112 86 * -1;
#X obj 46 109 phasor~;
#X obj 46 186 -~ 1;
#X obj 112 109 phasor~;
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#X msg 108 59 0;
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#X connect 6 0 2 1;
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#X connect 9 0 3 0;
#X connect 10 0 6 0;
#X connect 10 0 8 0;
'''triang~.pd'''
#N canvas 770 214 450 300 10;
#X obj 46 17 inlet;
#X obj 112 51 * -1;
#X obj 46 74 phasor~;
#X obj 46 95 *~ 2;
#X obj 46 116 -~ 1;
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'''pulse~.pd'''
#N canvas 784 384 450 300 10;
#X obj 51 56 phasor~;
#X obj 51 77 -~ 0.99;
#X obj 51 98 clip~ 0 1;
#X obj 51 119 *~ 100;
#X obj 51 140 outlet~;
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- Provides on/off switch, frequency and volume control and five different wave shapes to select from.
- Frequency may be typed in or changed by dragging. Predefined pitches and a frequency ramp (18 - 24000 Hz) are accessible by clicking the respective labels.
- Volume level and wave shape are graphically displayed.
- More shapes, even free wave shape modelling could easily be added.
Ring
# Project : Audio frequency generator
Load "guilib.ring"
loadlib("C:\Ring\extensions\ringbeep\ringbeep.dll")
freq = 1000
ImageFile = "stock.jpg"
UserIcons = CurrentDir() +"\"
WinLeft = 80
WinTop = 80
WinWidth = 1200
WinHeight = 750
WinRight = WinLeft + WinWidth
WinBottom = WinTop + WinHeight
BoxLeft = 80
BoxTop = 40
BoxWidth = WinWidth -160
BoxHeight = WinHeight -100
imageW = 400 ; imageH = 400 ; GrowBy = 8
volume = 100
MyApp = New qapp
{
win1 = new qMainWindow()
{
setwindowtitle("Video and Music Player")
setgeometry( WinLeft, WinTop, WinWidth, WinHeight)
if Fexists(ImageFile)
imageStock = new qlabel(win1)
{
image = new qpixmap(ImageFile)
AspectRatio = image.width() / image.height()
imageW = 1000
imageH = 600
setpixmap(image.scaled(imageW , imageH ,0,0))
PosLeft = (BoxWidth - imageW ) / 2 + 80
PosTop = (BoxHeight - imageH ) / 2 +40
setGeometry(PosLeft,PosTop,imageW,imageH)
}
else
msg = "ImageFile: -- "+ ImageFile +" -- required. Use an Image JPG of your choice"
SendMsg(msg)
ok
videowidget = new qVideoWidget(win1)
{
setgeometry(BoxLeft, BoxTop, BoxWidth, BoxHeight)
setstylesheet("background-color: green")
}
player = new qMediaPlayer()
{
setVideoOutput(videowidget)
}
TimerDuration = new qTimer(win1)
{
setinterval(1000)
settimeoutevent("pTimeDuration()") ### ==>> func
start()
}
oFont = new qFont("",10,0,0)
setFont( oFont)
btnBack = new qpushbutton(win1) {
setGeometry(280,20,80,20)
settext("Low")
seticon(new qicon(new qpixmap(UserIcons +"Backward.png")))
setclickevent( "pBackward()")
}
btnDur = new qpushbutton(win1) {
setGeometry(360,20,140,20)
}
btnFwd = new qpushbutton(win1) {
setGeometry(500,20,80,20)
settext("High")
seticon(new qicon(new qpixmap(UserIcons +"Forward.png")))
setclickevent( "pForward()")
}
btnVolume = new qpushbutton(win1) {
setGeometry(760,20,100,20)
settext("Volume: 100")
seticon(new qicon(new qpixmap(UserIcons +"Volume.png")))
}
VolumeDec = new qpushbutton(win1)
{
setgeometry(700,20,60,20)
settext("Low")
seticon(new qicon(new qpixmap(UserIcons +"VolumeLow.png")))
setclickevent( "PVolumeDec()")
}
VolumeInc = new qpushbutton(win1)
{
setgeometry(860,20,60,20)
settext("High")
seticon(new qicon(new qpixmap(UserIcons +"VolumeHigh.png")))
setclickevent( "pVolumeInc()")
}
show()
}
exec()
}
Func pTimeDuration()
Duration()
return
Func Duration()
DurPos = "Frequency: " + string(freq) + " Hz"
btnDur.setText(DurPos)
return
Func pForward
freq = freq + 100
for n = 1 to 3
beep(freq,300)
next
return
Func pBackward
freq = freq - 100
for n = 1 to 3
beep(freq,300)
next
return
Func pVolumeDec()
if volume > 0
volume = volume - 10
btnVolume.settext("Volume: " + volume)
player.setVolume(volume)
ok
return
Func pVolumeInc()
if volume < 100
volume = volume + 10
btnVolume.settext("Volume: " + volume)
player.setVolume(volume)
ok
return
Output:
[https://www.dropbox.com/s/jf5uq0bbts40wto/CalmoSoftFrequency.avi?dl=0 Audio frequency generator]
SuperCollider
SuperCollider is a sound programming language, so the task is predictably easy.
// the server application detects audio hardware.
Server.default.boot;
// play a sine monotone at 440 Hz and amplitude 0.2
{ SinOsc.ar(440) * 0.2 }.play;
// use the cursor position to adjust frequency and amplitude (ranges are exponential)
{ SinOsc.ar(MouseX.kr(40, 20000, 1)) * MouseY.kr(0.001, 0.5, 1) }.play;
// use the cursor position to switch between sine wave, square wave and triangular sawtooth
// the rounding and lag smoothes the transition between them
{ SelectX.ar(MouseX.kr(0, 2).round.lag, [ SinOsc.ar, Pulse.ar, LFTri.ar ]) * 0.1 }.play;
// the same expressed as an array of functions of a common phase
(
{
var phase = LFSaw.ar;
var functions = [
{ |x| sin(x * pi) },
{ |x| x > 0 },
{ |x| abs(x) },
];
var which = MouseX.kr(0, 2);
functions.sum { |f, i|
abs(which - i) < 0.5 * f.(phase)
} * 0.1
}.play
)
// sound stops on exit
Server.default.quit;
Tcl
{{libheader|Snack}} This does not work on Windows due the use of the external stty program.
package require sound set baseFrequency 261.63 set baseAmplitude [expr {64000 / 100.0}] set halfSemis 0 set volSteps 10 # How to adjust the generator proc adjustPitchVolume {changePitch changeVolume} { global filter baseFrequency baseAmplitude halfSemis volSteps incr halfSemis $changePitch incr volSteps $changeVolume # Clamp the volume range set volSteps [expr {$volSteps < 0 ? 0 : $volSteps > 10 ? 10 : $volSteps}] puts -nonewline " Pitch: [expr {$halfSemis / 2.0}] Volume: $volSteps \r" set freq [expr {$baseFrequency * 2**($halfSemis/24.0)}] set ampl [expr {$baseAmplitude * $volSteps**2}] # This is where we set the actual frequency of the generated sound $filter configure $freq $ampl } # Callback handler for pressed keys proc keyPress {} { global done switch [string tolower [read stdin 1]] { "q" { set done 1 } "u" { adjustPitchVolume 1 0 } "d" { adjustPitchVolume -1 0 } "s" { adjustPitchVolume 0 -1 } "l" { adjustPitchVolume 0 1 } default { if {[eof stdin]} { set done 1 } } } } # Instantiate the sound generation objects from the Snack library set filter [snack::filter generator 1 32000 0.5 sine -1] set sound [snack::sound -rate 32050] # Make things ready for a console application exec stty raw -echo <@stdin >@stdout fconfigure stdout -buffering none fileevent stdin readable keyPress puts "'U' to raise pitch, 'D' to lower pitch, 'L' for louder, 'S' for softer" puts "'Q' to quit" # Start the playing $sound play -filter $filter adjustPitchVolume 0 0 # Wait until the user is finished vwait done # Clean up the console from its non-standard state fileevent stdin readable {} puts "" exec stty -raw echo <@stdin >@stdout # Stop the sound playing $sound stop exit
ZX Spectrum Basic
The ZX Spectrum is not very good at making sound. Most applications in BASIC would just produce annoying beeps, and the following is no exception. To emulate the signal generator, we just produce repetative beeps using the inbuilt speaker. The left and right keys (5 and 8) change the tone. There is no volume control on the Spectrum.
10 REM The crappest signal generator in the world
20 REM We do not check for boundary errors in this simple demo
30 LET n=1
40 LET k$=INKEY$
50 IF k$="5" THEN LET n=n-0.5
60 IF k$="8" THEN LET n=n+0.5
70 PRINT AT 0,0;n," "
80 BEEP 0.1,n: REM beep for 0.1 second at n semitones relative to middle C
90 GO TO 40