mc.groove~

Variable-rate looping sample playback (multichannel)

Description

The groove~ object is a variable-rate, looping, sample-playback object which references the audio information stored in a buffer~ object having the same name.

Discussion

The interpolation for groove~ is cubic unless the timestretching attribute is set to 1. When timestretching is set to 1, you can control the quality of the conversion with the mode, quality, and formant attributes. The wave~ object provides additional interpolation options for buffer playback. The interpolation for groove~ is cubic unless the timestretching attribute is set to 1. When timestretching is set to 1, you can control the quality of the conversion with the mode, quality, and formant attributes. The wave~ object provides additional interpolation options for buffer playback.

Arguments

buffer-name [symbol]

Names the buffer~ object containing the sample to be used by groove~ for playback.

number-of-outputs [int]

Optional

A second argument may specify the number of output channels. The default number of channels is 1. If the buffer~ being played has fewer channels than the number of groove~ output channels, the extra channels output a zero signal. If the buffer~ has more channels and is a multiple of 2 or 4, channels are mixed. For groove~ and mc.groove~, channels and sent out of separate outlets. For mcs.groove~, all channels are output from the first outlet as a multi-channel signal.

Attributes

basictuning [int]7.0.0

Set a tuning standard based on a frequency for A for pitchshifting operations (440 = default, range is 400 - 500)

followglobaltempo [int]7.0.0

When followgobaltempo is enabled, groove~ will calculate the current tempo out of the ratio between originaltempo and global tempo and adapt to global tempo changes.

formant [float] (default: 1.)7.0.0

The word formant, followed by floating point value, sets the amount of formant scaling when pitchshifting is performed.

formantcorrection [int]7.0.0

The word formantcorrection, followed by a zero or one, disables/enables formant correction when pitch correction is performed.

lock [int] (default: 0)7.0.0

Lock to transport

loop [int]

The word loop, followed by a zero or one, disables/enables looping.

loopend [10 atoms]

Sets the loop end point. The end point time can be specified in any of the Max time formats.

loopinterp [int]

The word loopinterp, followed by 1, enables interpolation about start and end points for a loop. loop 0 turns off loop interpolation. By default, loop interpolation is off. Turning loop interpolation on disables resampling.

loopstart [10 atoms]

Sets the loop start point. The start point time can be specified in any of the Max time formats.

mode [int]7.0.0

Set the timestretching mode to be used. Each mode is optimized for handling different kinds of audio material. All modes are zero latency. The interpolation for groove~ is cubic unless the timestretching attribute is set to 1. When timestretching is set to 1, you can control the quality of the conversion with the mode, quality, and formant attributes.


Possible values:

'basic' ( Default mode of operation )
This is the default mode of operation.

'monophonic' ( Monophonic sources (voice, flute) )
This mode is best for monophonic instruments (e.g. solo voice, flute, etc.)

'rhythmic' ( Optimizes for transient preservation )
This mode is for time stretched percussion. It provides optimal transient preservation.

'general' ( Balance spectral integrity with transient preservaton )
This mode balances spectral integrity and transient preservation for general cases.

'extremestretch' ( For stretch ratios greater than 2.0 )
This mode is intended for stretch ratios greater 2.0, a more artistic effect is intended.

'efficient' ( Good CPU performance )
This mode is intended for a good CPU performance/quality tradeoff.

originallength [10 atoms]7.0.0

The original length of the the audio file in beats. Used by followglobaltempo to calculate the speed in relation to the global transport speed. Set originallength to calculate the originaltempo.

originaltempo [float]7.0.0

The original tempo of the the audio file. Used by followglobaltempo to calculate the speed relative to the global transport speed. Setting the originaltempo will calculate the originallength.

phase [10 atoms]7.0.0

Phase

pitchcorrection [int]7.0.0

The word pitchcorrection, followed by a zero or one, enable/disables the formant-corrected chromatic intonation correction. For more extensive real-time intonation correction, use the retune~ object.

pitchshift [float] (default: 1.)7.0.0

Specifies pitchshift as a factor of the original pitch (i.e. 2.0 = doubling of pitch, .5 = halving of the original pitch, etc.).

pitchshiftcent [int] (default: 0)7.0.0

Specifies pitchshift as positive or negative cent values (i.e. 100 = semitone up, -1200 = octave down). Cents may be specified as ints or floats.

quality [int]7.0.0

Timestretching output quality.


Possible values:

'basic' ( Basic quality (the default) )
'good' ( Good quality )
'better' ( Better quality )
'best' ( Highest quality )

slurtime [float] (default: 0.)7.0.0

Set the time it takes for the correction to reach the full correction amount. Typically, notes are a bit unstable at the beginning, because the attack phase of a sound has a higher amount of noise, and because singers gradually adjust their tuning after the onset of the note. The slur time makes the pitch correction sound natural because it models this effect. Higher values will yield a slower adaptation time and it will take longer for the correction to produce the corrected pitch. However, longer slur times will also preserve vibrato better.

timestretch [int]7.0.0

The word timestretch, followed by a zero or one, disables/enables timestretching.

transport [symbol]

Sets the name of a transport object with which to associate. By default, the global transport is used. When the groove~ object is associated with a transport, loop points are specified using 3-item lists which correspond to time in bars, beats, and units.

Common Box Attributes

annotation [symbol]

Sets the text that will be displayed in the Clue window when the user moves the mouse over the object.

background [int] (default: 0)

Adds or removes the object from the patcher's background layer. background 1 adds the object to the background layer, background 0 removes it. Objects in the background layer are shown behind all objects in the default foreground layer.

color [4 floats]

Sets the color for the object box outline.

fontface [int]

Sets the type style used by the object. The options are:

plain
bold
italic
bold italic

Possible values:

0 = 'regular'
1 = 'bold'
2 = 'italic'
3 = 'bold italic'

fontname [symbol]

Sets the object's font.

fontsize [float]

Sets the object's font size (in points).

Possible values:

'8'
'9'
'10'
'11'
'12'
'13'
'14'
'16'
'18'
'20'
'24'
'30'
'36'
'48'
'64'
'72'

hidden [int] (default: 0)

Toggles whether an object is hidden when the patcher is locked.

hint [symbol]

Sets the text that will be displayed in as a pop-up hint when the user moves the mouse over the object in a locked patcher.

ignoreclick [int] (default: 0)

Toggles whether an object ignores mouse clicks in a locked patcher.

patching_rect [4 floats] (default: 0. 0. 100. 0.)

Sets the position and size of the object in the patcher window.

position [2 floats]

g/s(set)

Sets the object's x and y position in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its size unchanged.

presentation [int] (default: 0)

Sets whether an object belongs to the patcher's presentation.

presentation_rect [4 floats] (default: 0. 0. 0. 0.)

Sets the x and y position and width and height of the object in the patcher's presentation, leaving its patching position unchanged.

rect [4 floats]

g/s(set)

Sets the x and y position and width and height of the object in both patching and presentation modes (if the object belongs to its patcher's presentation).

size [2 floats]

g/s(set)

Sets the object's width and height in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its position unchanged.

textcolor [float]

Sets the color for the object's text in RGBA format.

textjustification [int]

Text Justification

Possible values:

0 = 'left'
1 = 'center'
2 = 'right'

varname [symbol]

Sets the patcher's scripting name, which can be used to address the object by name in pattr, scripting messages to thispatcher, and the js object.

Multichannel Group Attributes

chans [int]

The chans attribute sets the number of channels and instances in the MC wrapper object. If you want a fixed number of channels regardless of what is connected to the object, you could set chans via a typed-in argument, for example typing mc.cycle~ @chans 100 would create 100 instances of a cycle~ object inside the MC wrapper. If chans is 0, the wrapper object will auto-adapt to the number of channels in its input multichannel signals (using the maximum of all connected signals). For objects without connected multichannel signals, the chans attribute will need to have a non-zero value if you want more than one instance.

If chans is changed while the audio is on, the number of instances will not updated until audio is restarted. However, if chans is reduced while the audio is on, any extra channels will no longer process audio and will output a zero signal.

values [int]

The values attribute only applies to object creation time so it must be set via typed-in argument syntax. values sets the first (and only the first) initial argument for successive instances in the MC wrapper. For example, typing mc.cycle~ @chans 4 @values 50 60 70 80 would assign an initial frequency to the cycle~ instances inside the wrapper. The first instance would be assigned a frequency of 50, the second a frequency of 60, the third 70, and the fourth 80. Note that values does not determine the actual instance count; this can be done using the chans attribute. If there are more instances than elements for the values attribute, those instances are instantiated with the default value.

If you want to set a default initial value for all instances, simply type it as an argument before any typed-in attributes. For example, modifying our example above: mc.cycle~ 100 @chans 10 @values 50 60 70 80. In this example, the first four instances are set as before, but the next six are created with a frequency argument of 100.

To change instance values or attributes after the wrapper object has been created, use the setvalue, applyvalues, or replicatevalues messages.

replicate [int]

When replicate is enabled, input single-channel or multichannel signals containing fewer channels than the number instances in the MC wrapper object are repeated to fill all input channels. For example, when replicate is enabled and you connect a two-channel multichannel signal to the input of an MC wrapper object with four instances, channel 1 of the input will be repeated to channel 3, and channel 2 of the input will be repeated to channel 4. If replicate were disabled, channels 3 and 4 of the input would be set to zero.

target [int]

The target attribute sets a voice index for targeting specific wrapper instances. Subsequent messages are directed to an individual instance instead of all instances. It is strongly recommended you use the more reliable setvalue message instead of the target attribute. The voice index of setvalue will override the current setting of target. When target is 0, incoming messages are sent to all instances. When target is -1, incoming messages do nothing.

usebusymap [int]

When usebusymap is enabled, the MC wrapper controls whether individual instances process audio using a busy map maintained by either an mc.noteallocator~ or mc.voiceallocator~ object. When a channel in the busy map is marked as "free" or "released" no audio processing occurs by any instance on the channel corresponding to the voice index. When usebusymap is disabled, instances in the MC wrapper process audio at all times. This will also be true if usebusymap is enabled and there is no local or named busy map available. (See the busymapname attribute for a description of local and named busy maps).

zero [int]

When the zero attribute is enabled, channels in the MC wrapper due to the use of a busy map output zero signals. To save a small amount of CPU at the risk of loud and unpleasant noises due to uncleared signal data, you can disable zero. In this case, disabled channels in the MC wrapper do nothing to their output channels. If usebusymap is disabled or there is no active local or named busy map available, the setting of the zero attribute has no effect.

Conveniently, when usebusymap is enabled in mc.mixdown~ object, disabled channels are not mixed to the output. When unused signals from wrapped objects with zero disabled feed into mc.mixdown~, they will be ignored, reducing the risk of unpleasantness getting past the mix output.

busymapname [symbol]

When the usebusymap attribute is enabled, an MC wrapper object uses the local busy map of any mc.voiceallocator~ or mc.noteallocator~ in the same patcher by default. To use a named global busy map instead, set the busymapname attribute to the desired name.

Messages

int

Arguments

playback-position [int]
In all inlets: Converted to float.

In left inlet: Sets the sample playback position in milliseconds. 0 sets the playback position to the beginning.
In middle inlet: Sets the sample playback start position in milliseconds.
In right lnlet: Sets the sample playback start position in milliseconds.

float

Arguments

playback-position [float]
In left inlet: Sets the sample playback position in milliseconds. 0 sets the playback position to the beginning.
In middle inlet: Sets the sample playback start position in milliseconds.
In right lnlet: Sets the sample playback start position in milliseconds.

list

Arguments

bars [int]
beats [int]
units [int]
In middle inlet: A list composed of three integers specifying bars, beats, and units may be used to specify the loop start point when the groove~ object is set to follow a named transport (set using the transport attribute).

In right inlet: A list composed of three integers specifying bars, beats, and units may be used to specify the loop end point when the groove~ object is set to follow a named transport (set using the transport attribute).

anything

Arguments

bars [int]
beats [int]
units [int]
In middle inlet: A list composed of three integers specifying bars, beats, and units may be used to specify the loop start point when the groove~ object is set to follow a named transport (set using the transport attribute).

In right inlet: A list composed of three integers specifying bars, beats, and units may be used to specify the loop end point when the groove~ object is set to follow a named transport (set using the transport attribute).

clearspeedcues7.0.0

Clear the speed cues that have been defined via a dictionary.

(mouse)

Double-clicking on a groove~ object opens the sample display window of the buffer~ object associated with the groove~ object.

dictionary7.0.0

Arguments

dictionary-name [symbol]
Use a dictionary to define more complex stretching and pitch shifting. Define a point in time (sourcetime, sourcetimesample or sourcetimebbu) and define where this point should be transformed to (desttime, desttimesample or desttimebbu). For example, the dictionary below will
  • create marker01 which will stretch the file so that the audio at 500 ms will be on the first bar, will pitch-shift the audio down by 100 cents until the next marker
  • create marker02 which will stretch so the material at 1000 ms will be at 1.2.0 bbu, will pitch-shift the audio by a factor of 1.1 up until the next marker
  • create marker03 which will stretch the whole sample (“end”) to be twice as long
{ "marker01" : { "sourcetime" : "500", "desttimebbu" : "1.0.0", "pitchshiftcent" : -100 } , "marker02" : { "sourcetime" : 1000, "desttime" : 1.2.0, "pitchshift" : 1.1 } , "marker03" : { "sourcetime" : “end”, "desttime" : “*2”, } }

printspeedcues7.0.0

Print the currently active speed cues that have been defined via a dictionary.

reset

Clear the start and end loop points

set

Arguments

buffer-name [symbol]
The word set, followed by a symbol, switches the buffer~ object containing the sample to be used by groove~ for playback.

setloop

Arguments

start-point [list]
end-point [list]
The word setloop, followed by two numbers, sets the start and end loop points in milliseconds.

signal

In left inlet: Defines the sample increment for playback of a sound from a buffer~. A sample increment of 0 stops playback. A sample increment of 1 plays the sample at normal speed. A sample increment of -1 plays the sample backwards at normal speed. A sample increment of 2 plays the sample at twice the normal speed. A sample increment of .5 plays the sample at half the normal speed. The sample increment can change over time for vibrato or other types of speed effects. The groove~ object uses the buffer~ sampling rate to determine playback speed.

If a loop start and end have been defined for groove~ and looping is turned on, when the sample playback reaches the loop end the sample position is set to the loop start and playback continues at the current sample increment.

In middle inlet: Sets the starting point of the loop in milliseconds.

In right inlet: Sets the end point of the loop in milliseconds.

startloop

Causes groove~ to begin sample playback at the starting point of the loop. If no loop has been defined, groove~ begins playing at the beginning.

stop

The word stop will cause groove~ to stop playback until the next int, float, or startloop message is received.

Multichannel Group Messages

deviate

Arguments

range [float]
message-name [symbol]
center-value [float]
Generate a random value for each channel around a center value. If no message name is provided then a float message is used by default.

exponential

Arguments

exponent [float]
base [float]
The exponential message generates an exponential series using the second argument as a base and the first argument as an exponent.

scaledexponential

Arguments

exponent [float]
base [float]
The scaledexponential message generates an exponential series using the second argument as a base and the first argument as an exponent. Values are scaled by the instance number, so the total range of the series is independent of the number of channels.

increment

Arguments

increment-amount [float]
message-name [symbol]
start-value [float]
Generate a increasing value for each channel starting at a specified value. If no message name is provided then a float message is used by default.

harmonic

Arguments

multiplier [float]
fundamental [float]
The harmonic message generate a harmonic series using the second argument as the fundamental frequency and the first argument as a multiplier.

subharmonic

Arguments

multiplier [float]
fundamental [float]
The subharmonic message generate a subharmonic series using the second argument as the fundamental frequency and the first argument as a multiplier.

spread

Arguments

boundary-value [float]
message-name [symbol]
other-boundary-value [float]
Generate a range of values distributed to each channel. If no message name is provided then a float message is used by default. The first boundary value is included in the range outputs, but the last boundary value is not.

spreadinclusive

Arguments

boundary-value [float]
message-name [symbol]
other-boundary-value [float]
Generate a range of values distributed to each channel. If no message name is provided then a float message is used by default. Both the first and last boundary values are included in the range outputs.

spreadexclusive

Arguments

boundary-value [float]
message-name [symbol]
other-boundary-value [float]
Generate a range of values distributed to each channel. If no message name is provided then a float message is used by default. Neither the first nor last boundary values are included in the range outputs.

spreadincludefirst

Arguments

boundary-value [float]
message-name [symbol]
other-boundary-value [float]
Generate a range of values distributed to each channel. If no message name is provided then a float message is used by default. The first boundary value is included in the range outputs, but the last boundary value is not. The spreadincludefirst message is the same as the spread message.

spreadincludesecond

Arguments

boundary-value [float]
message-name [symbol]
other-boundary-value [float]
Generate a range of values distributed to each channel. If no message name is provided then a float message is used by default. The first boundary value is not included in the range outputs, but the last boundary value is included.

setvalue

Arguments

channel [int]
message [symbol]
message arguments [list]
The word setvalue, followed by both a channel index (starting at 1) and any message that can be sent to the wrapped object, sends the message to an individual instance within the MC wrapper. setvalue 0, followed by a message, sends the message to all instances. The setvalue message can be used in any inlet.

applyvalues

Arguments

message-name [symbol]
values [list]
The word applyvalues, followed by an optional message name and one or more message arguments, sends individual values in the arguments successively to instances in the MC wrapper, starting with the first instance. For example, the message applyvalues 4 5 6 will send 4 to the first instance, 5 to the second instance, and 6 to the third instance. If there are more instances than arguments to applyvalues, the extra instances are unaffected.

replicatevalues

Arguments

message-name [symbol]
values [list]
The word replicatevalues, followed by an optional message name and one or more message arguments, sends individual values in the arguments successively to instances in the MC wrapper, starting with the first instance. Unlike applyvalues, the replicatevalues message continues sending values to successive instances, restarting with the first element, if it runs out of arguments to send. For example, replicatevalues 4 5 to an MC wrapper object with three instances will send 4 to the first instance, 5 to the second instance, and 4 to the third instance.

Output

signal

Out left outlet: Sample output. If groove~ or mc.groove~ has two or four output channels, the left outlet plays the left channel of the sample. For mcs.groove~, all channels are output from the left outlet.

Out middle outlets: Sample output. If groove~ or mc.groove~ has two or four output channels, the middle outlets play the channels other than the left channel. mcs.groove~ does not have middle outlets, so this does not apply for that object.

Out right outlet: Sync output. During the loop portion of the sample, this outlet outputs a signal that goes from 0. when the loop starts to 1. when the loop ends.
Note: In order for buffer playback to begin (and consequently for sync output), one of the groove~ object's output channels must be connected to another signal object.

See Also

Name Description
2d.wave~ Two-dimensional wavetable
buffer~ Store audio samples
play~ Position-based sample playback
wave~ Variable size wavetable
index~ Read from a buffer~ with no interpolation
record~ Record sound into a buffer
transport Control a master clock
MSP Sampling Tutorial 3: Playback with Loops MSP Sampling Tutorial 3: Playback with Loops
MSP MIDI Tutorial 3: MIDI Sampler MSP MIDI Tutorial 3: MIDI Sampler