| window.runtime property | window.runtime.flash.media.Microphone |
| Inheritance | Microphone EventDispatcher |
| Runtime Versions: | 1.0 |
For information about capturing video, see the Camera class.
Important: Flash Player displays a Privacy dialog box that lets the user choose whether to allow or deny access to the microphone. Make sure that your application window size is at least 215 x 138 pixels, which is the minimum size required to display the dialog box.
To create or reference a Microphone object, use the Microphone.getMicrophone() method.
| Property | Defined By | ||
|---|---|---|---|
| activityLevel : Number [read-only]
The amount of sound the microphone is detecting. | Microphone | ||
| codec : String
The codec to use for compressing audio. | Microphone | ||
| encodeQuality : int
The encoded speech quality when using the Speex codec. | Microphone | ||
| framesPerPacket : int
Number of Speex speech frames transmitted in a packet (message). | Microphone | ||
| gain : Number
The microphone gain—that is, the amount by which the microphone multiplies the signal before
transmitting it. | Microphone | ||
| index : int [read-only]
The index of the microphone, as reflected in the array returned by
Microphone.names. | Microphone | ||
| muted : Boolean [read-only]
Specifies whether the user has denied access to the microphone (true)
or allowed access (false). | Microphone | ||
| name : String [read-only]
The name of the current sound capture device, as returned by the sound capture hardware. | Microphone | ||
| names : Array [static] [read-only]
An array of strings containing the names of all available sound capture devices. | Microphone | ||
| rate : int
The rate at which the microphone captures sound, in kHz. | Microphone | ||
| silenceLevel : Number [read-only]
The amount of sound required to activate the microphone and dispatch
the activity event. | Microphone | ||
| silenceTimeout : int [read-only]
The number of milliseconds between the time the microphone stops
detecting sound and the time the activity event is dispatched. | Microphone | ||
| soundTransform : SoundTransform
Controls the sound of this microphone object when it is in loopback mode. | Microphone | ||
| useEchoSuppression : Boolean [read-only]
Set to true if echo suppression is enabled; false otherwise. | Microphone | ||
| Method | Defined By | ||
|---|---|---|---|
![]() | addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object with an EventDispatcher object so that the listener
receives notification of an event. | EventDispatcher | |
![]() |
Dispatches an event into the event flow. | EventDispatcher | |
[static]
Returns a reference to a Microphone object for capturing audio. | Microphone | ||
![]() |
Checks whether the EventDispatcher object has any listeners registered for a specific type
of event. | EventDispatcher | |
![]() |
Removes a listener from the EventDispatcher object. | EventDispatcher | |
setLoopBack(state:Boolean = true):void
Routes audio captured by a microphone to the local speakers. | Microphone | ||
Sets the minimum input level that should be considered sound and (optionally) the amount
of silent time signifying that silence has actually begun. | Microphone | ||
setUseEchoSuppression(useEchoSuppression:Boolean):void
Specifies whether to use the echo suppression feature of the audio codec. | Microphone | ||
![]() |
Checks whether an event listener is registered with this EventDispatcher object or any of
its ancestors for the specified event type. | EventDispatcher | |
| Event | Summary | Defined By | ||
|---|---|---|---|---|
![]() | [broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active. | EventDispatcher | ||
| Dispatched when a microphone begins or ends a session. | Microphone | |||
![]() | [broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive. | EventDispatcher | ||
| Dispatched when a microphone reports its status. | Microphone | |||
| activityLevel | property |
activityLevel:Number [read-only] | Runtime Versions: | 1.0 |
The amount of sound the microphone is detecting. Values range from
0 (no sound is detected) to 100 (very loud sound is detected). The value of this property can
help you determine a good value to pass to the Microphone.setSilenceLevel() method.
If the microphone is available but is not yet being used because Microphone.getMicrophone()
has not been called, this property is set to -1.
See also
| codec | property |
codec:String| Runtime Versions: | 1.5 |
The codec to use for compressing audio. The default codec used is the Nellymoser codec.
The enumeration class SoundCodec contains the various values that are valid for the codec property.
See also
| encodeQuality | property |
encodeQuality:int| Runtime Versions: | 1.5 |
The encoded speech quality when using the Speex codec. Possible values are from 0 to 10. The default value is 6. Higher numbers represent higher quality but require more bandwidth, as shown in the following table. The bit rate values that are listed represent net bit rates and do not include packetization overhead.
| Quality value | Required bit rate (kilobits per second) |
|---|---|
| 0 | 3.95 |
| 1 | 5.75 |
| 2 | 7.75 |
| 3 | 9.80 |
| 4 | 12.8 |
| 5 | 16.8 |
| 6 | 20.6 |
| 7 | 23.8 |
| 8 | 27.8 |
| 9 | 34.2 |
| 10 | 42.2 |
See also
| framesPerPacket | property |
framesPerPacket:int| Runtime Versions: | 1.5 |
Number of Speex speech frames transmitted in a packet (message). Each frame is 20 ms long. The default value is two frames per packet.
The more Speex frames in a message, the lower the bandwidth required but the longer the delay in sending the message. Fewer Speex frames increases bandwidth required but reduces delay.
| gain | property |
gain:Number| Runtime Versions: | 1.0 |
The microphone gain—that is, the amount by which the microphone multiplies the signal before transmitting it. A value of 0 tells Flash Player to multiply by 0; that is, the microphone transmits no sound.
You can think of this setting like a volume knob on a stereo: 0 is no volume and 50 is normal volume. Numbers below 50 specify lower than normal volume, while numbers above 50 specify higher than normal volume. Valid values are 0 through 100, and 50 is the default value. The user can change this value in the Flash Player Microphone Settings panel.
See also
| index | property |
index:int [read-only] | Runtime Versions: | 1.0 |
The index of the microphone, as reflected in the array returned by
Microphone.names.
See also
| muted | property |
muted:Boolean [read-only] | Runtime Versions: | 1.0 |
Specifies whether the user has denied access to the microphone (true)
or allowed access (false). When this value changes,
a status event is dispatched.
For more information, see Microphone.getMicrophone().
See also
| name | property |
name:String [read-only] | Runtime Versions: | 1.0 |
The name of the current sound capture device, as returned by the sound capture hardware.
See also
| names | property |
names:Array [read-only] | Runtime Versions: | 1.0 |
An array of strings containing the names of all available sound capture devices.
The names are returned without
having to display the Flash Player Privacy Settings panel to the user. This array
provides the zero-based index of each sound capture device and the
number of sound capture devices on the system, through the Microphone.names.length property.
For more information, see the Array class entry.
Calling Microphone.names requires an extensive examination of the hardware, and it
may take several seconds to build the array. In most cases, you can just use the default microphone.
Note: To determine the name of the current microphone,
use the name property.
See also
| rate | property |
rate:int| Runtime Versions: | 1.0 |
The rate at which the microphone captures sound, in kHz. The allowed values are any of the following your sound device supports: 5, 8, 11, 22, or 44.
The default value is 8 kHz if your sound capture device supports this value. Otherwise, the default value is the next available capture level above 8 kHz that your sound capture device supports, usually 11 kHz.
| silenceLevel | property |
silenceLevel:Number [read-only] | Runtime Versions: | 1.0 |
The amount of sound required to activate the microphone and dispatch
the activity event. The default value is 10.
See also
| silenceTimeout | property |
silenceTimeout:int [read-only] | Runtime Versions: | 1.0 |
The number of milliseconds between the time the microphone stops
detecting sound and the time the activity event is dispatched. The default
value is 2000 (2 seconds).
To set this value, use the Microphone.setSilenceLevel() method.
See also
| soundTransform | property |
soundTransform:SoundTransform| Runtime Versions: | 1.0 |
Controls the sound of this microphone object when it is in loopback mode.
| useEchoSuppression | property |
useEchoSuppression:Boolean [read-only] | Runtime Versions: | 1.0 |
Set to true if echo suppression is enabled; false otherwise. The default value is
false unless the user has selected Reduce Echo in the Flash Player Microphone Settings panel.
See also
| getMicrophone | () | method |
function getMicrophone(index:int = -1):Microphone| Runtime Versions: | 1.0 |
Returns a reference to a Microphone object for capturing audio.
To begin capturing the audio, you must attach the Microphone
object to a NetStream object (see NetStream.attachAudio()).
Multiple calls to Microphone.get() reference the same microphone.
Thus, if your code contains the lines mic1 = Microphone.get() and
mic2 = Microphone.get(), both mic1 and mic2
reference the same (default) microphone.
If you want to get the default microphone, you need to call getMicrophone() with -1.
If you call it without parameters, it will return the first microphone in the list.
Use the index property to get the index value of the current
Microphone object. You can then pass this value to other methods of the
Microphone class.
In general, you should not pass a value for index. Simply use the
Microphone.getMicrophone() method to return a reference to the default microphone.
By using the Microphone Settings panel, the user can specify the default
microphone the application should use. If you pass a value for index, you might
reference a microphone other than the one the user chooses. You can use index in
rare cases—for example, if your application is capturing audio from two microphones
at the same time.
When a SWF file tries to access the object returned by Microphone.getMicrophone()
—for example, when you call NetStream.attachAudio()—
Flash Player displays a Privacy dialog box that lets the user choose whether to
allow or deny access to the microphone. (Make sure your Stage size is at least
215 x 138 pixels; this is the minimum size Flash Player requires to display the dialog box.)
When the user responds to this dialog box, a status event is dispatched
that indicates the user's response. You can also check the Microphone.muted
property to determine if the user has allowed or denied access to the microphone.
If Microphone.getMicrophone() returns null, either the microphone is in use
by another application, or there are no microphones installed on the system. To determine
whether any microphones are installed, use Microphones.names.length. To display
the Flash Player Microphone Settings panel, which lets the user choose the microphone to be
referenced by Microphone.getMicrophone, use Security.showSettings().
Parameters
index:int (default = -1) — The index value of the microphone.
|
Microphone — A reference to a Microphone object for capturing audio.
|
status: — Dispatched when a microphone reports its status.
If the value of the code property is "Microphone.Muted",
the user has refused to allow the SWF file access to the user's microphone.
If the value of the code property is "Microphone.Unmuted",
the user has allowed the SWF file access to the user's microphone. |
See also
| setLoopBack | () | method |
function setLoopBack(state:Boolean = true):void| Runtime Versions: | 1.0 |
Routes audio captured by a microphone to the local speakers.
Parameters
state:Boolean (default = true) |
| setSilenceLevel | () | method |
function setSilenceLevel(silenceLevel:Number, timeout:int = -1):void| Runtime Versions: | 1.0 |
Sets the minimum input level that should be considered sound and (optionally) the amount of silent time signifying that silence has actually begun.
silenceLevel; the activity event is never dispatched. Microphone.activityLevel. Activity detection is the ability to detect when audio levels suggest that a person is talking. When someone is not talking, bandwidth can be saved because there is no need to send the associated audio stream. This information can also be used for visual feedback so that users know they (or others) are silent.
Silence values correspond directly to activity values. Complete silence is an activity value of 0. Constant loud noise (as loud as can be registered based on the current gain setting) is an activity value of 100. After gain is appropriately adjusted, your activity value is less than your silence value when you're not talking; when you are talking, the activity value exceeds your silence value.
This method is similar to Camera.setMotionLevel(); both methods are used to
specify when the activity event is dispatched. However, these methods have
a significantly different impact on publishing streams:
Camera.setMotionLevel() is designed to detect motion and does not affect bandwidth
usage. Even if a video stream does not detect motion, video is still sent.Microphone.setSilenceLevel() is designed to optimize bandwidth. When an audio
stream is considered silent, no audio data is sent. Instead, a single message is sent, indicating
that silence has started. Parameters
silenceLevel:Number — The amount of sound required to activate the microphone
and dispatch the activity event. Acceptable values range from 0 to 100.
| |
timeout:int (default = -1) — The number of milliseconds that must elapse without
activity before Flash Player or Adobe AIR considers sound to have stopped and dispatches the
dispatch event. The default value is 2000 (2 seconds).
(Note: The default value shown
in the signature, -1, is an internal value that indicates to Flash Player or Adobe AIR to use 2000.)
|
See also
| setUseEchoSuppression | () | method |
function setUseEchoSuppression(useEchoSuppression:Boolean):void| Runtime Versions: | 1.0 |
Specifies whether to use the echo suppression feature of the audio codec. The default value is
false unless the user has selected Reduce Echo in the Flash Player Microphone
Settings panel.
Echo suppression is an effort to reduce the effects of audio feedback, which is caused when sound going out the speaker is picked up by the microphone on the same computer. (This is different from echo cancellation, which completely removes the feedback.)
Generally, echo suppression is advisable when the sound being captured is played through
speakers — instead of a headset — on the same computer. If your SWF file allows users to specify the
sound output device, you may want to call Microphone.setUseEchoSuppression(true)
if they indicate they are using speakers and will be using the microphone as well.
Users can also adjust these settings in the Flash Player Microphone Settings panel.
Parameters
useEchoSuppression:Boolean — A Boolean value indicating whether echo suppression should be used
(true) or not (false).
|
See also
| activity | Event |
flash.events.ActivityEventflash.events.ActivityEvent.ACTIVITY| Runtime Versions: | 1.0 |
Dispatched when a microphone begins or ends a session.
To specify the amount of sound required to trigger this event
with an activating property of true,
or the amount of time that must elapse without sound to
trigger this event with an activating property of
false, use Microphone.setSilenceLevel().
ActivityEvent.ACTIVITY constant defines the value of the type property of an activity event object.
This event has the following properties:
| Property | Value |
|---|---|
activating | true if the device is activating or false if it is deactivating. |
bubbles | false |
cancelable | false; there is no default behavior to cancel. |
currentTarget | The object that is actively processing the Event object with an event listener. |
target | The object beginning or ending a session, such as a Camera or Microphone object. |
See also
| status | Event |
flash.events.StatusEventflash.events.StatusEvent.STATUS| Runtime Versions: | 1.0 |
Dispatched when a microphone reports its status.
If the value of the code property is "Microphone.Muted",
the user has refused to allow the SWF file access to the microphone.
If the value of the code property is "Microphone.Unmuted",
the user has allowed the SWF file access to the microphone.
type property of a status event object.
This event has the following properties:
| Property | Value |
|---|---|
bubbles | false |
cancelable | false; there is no default behavior to cancel. |
code | A description of the object's status. |
currentTarget | The object that is actively processing the Event object with an event listener. |
level | The category of the message, such as "status", "warning" or "error". |
target | The object reporting its status. |
See also