#include <mdaaudioinputstream.h>
Link against: mediaclientaudioinputstream.lib
class CMdaAudioInputStream : public CBase, public MMMFClientUtility |
Public Member Functions | |
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~CMdaAudioInputStream() | |
IMPORT_C TInt | BitRateL() |
IMPORT_C TAny * | CustomInterface(TUid) |
IMPORT_C TFourCC | DataType() |
IMPORT_C TInt | Gain() |
IMPORT_C TInt | GetBalanceL() |
IMPORT_C TInt | GetBytes() |
IMPORT_C void | GetSupportedBitRatesL(RArray< TInt > &) |
IMPORT_C TInt | MaxGain() |
IMPORT_C CMdaAudioInputStream * | NewL(MMdaAudioInputStreamCallback &) |
IMPORT_C CMdaAudioInputStream * | NewL(MMdaAudioInputStreamCallback &, TInt, TInt) |
IMPORT_C void | Open(TMdaPackage *) |
IMPORT_C const TTimeIntervalMicroSeconds & | Position() |
IMPORT_C void | ReadL(TDes8 &) |
IMPORT_C void | RequestStop() |
IMPORT_C void | SetAudioPropertiesL(TInt, TInt) |
IMPORT_C void | SetBalanceL(TInt) |
IMPORT_C void | SetBitRateL(TInt) |
IMPORT_C void | SetDataTypeL(TFourCC) |
IMPORT_C void | SetGain(TInt) |
IMPORT_C void | SetPriority(TInt, TInt) |
IMPORT_C void | SetSingleBufferMode(TBool) |
IMPORT_C void | Stop() |
The interface to an audio stream player passing raw audio data from the audio hardware to specified buffers.
This class enables MMF clients to:
Stream raw audio data from the audio hardware to specified buffers.
Specify the priority of the audio stream in relation to other clients that may request to use the same audio hardware.
Set the sample rate and the number of channels after successfully opening the stream. It is not possible to
change these values once streaming has started.
Change the gain and balance before or while streaming is in progress. Gain and balance settings take effect immediately.
The API supports callbacks from the server to notify the client:
MaiscOpenComplete() will be called when the audio streaming object is open and ready to stream data back to the
user as a result of a previous call to Open().
MaiscBufferCopied() will be called multiple times while the FIFO (queued via ReadL()) is emptied.
Note: Each buffer will be flagged with KErrAbort if received after Stop() on is called. MaiscRecordComplete is called
once all remaining buffers have been read.
MaiscRecordComplete() is called after Stop() has been called. aError - KErrAbort if MaiscRecordComplete called
as a result of a call to Stop().
Users of object CMdaAudioInputStream should ensure that implementation of the callback methods MaiscOpenComplete,MaiscBufferCopied
and MaiscRecordComplete in class MMdaAudioInputStreamCallback do not delete the object,otherwise a Kern-Exec 3 would occur during callback.
~CMdaAudioInputStream | ( | ) |
Destructor.
Frees all resources owned by the object prior to its destruction.
IMPORT_C TInt | BitRateL | ( | ) | const |
Returns the current bit rate.
Leave Codes | |
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KErrNotSupported |
Retrieves a custom interface to the underlying device.
implement the interface requested. The return value must be cast to the
correct type by the user.
Parameters | |
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aInterfaceId | The interface UID, defined with the custom interface. |
IMPORT_C TInt | GetBalanceL | ( | ) | const |
Returns the current audio balance.
IMPORT_C TInt | GetBytes | ( | ) |
Returns the current number of bytes rendered by audio hardware.
Returns the bit rates supported by the sound device
The supported bit rates, in bits per second, shall be appended to this array. Note that
the array shall be reset by this method.
Leave Codes | |
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KErrNotSupported |
IMPORT_C TInt | MaxGain | ( | ) | const |
Returns the maximum gain level.
IMPORT_C CMdaAudioInputStream * | NewL | ( | MMdaAudioInputStreamCallback & | aCallBack | ) | [static] |
Instantiates a new audio input stream using default priority preferences.
for use, when data has been copied to a specified descriptor and when input streaming is
stopped. The caller must create a callback class that implements this interface.
UserEnvironment capability.
Static NewL
Parameters | |
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aCallBack | A callback to notify the client when the input stream has been initialised and is ready |
Capability | |
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UserEnvironment |
IMPORT_C CMdaAudioInputStream * | NewL | ( | MMdaAudioInputStreamCallback & | aCallBack, |
TInt | aPriority, | |||
TInt | aPref | |||
) | [static] |
Instantiates a new audio input stream.
use. The caller must create a callback class which implements this interface.
EMdaPriorityMax and represents a relative priority. A higher value indicates a more important request.
EMdaPriorityPreferenceNone. Further values are given by TMdaPriorityPreference, and additional
values may be supported by given phones and/or platforms, but should not be depended upon by
portable code.
UserEnvironment capability.
Note: The Priority Value and Priority Preference are used primarily when deciding what to do when
several audio clients attempt to play or record simultaneously. In addition to the Priority Value and Preference,
the adaptation may consider other parameters such as the SecureId and Capabilities of the client process.
Whatever, the decision as to what to do in such situations is up to the audio adaptation, and may
vary between different phones. Portable applications are advised not to assume any specific behaviour.
Static NewL
Parameters | |
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aCallBack | A callback to notify the client when the input stream has been initialised and is ready for |
aPriority | The Priority Value - this client's relative priority. This is a value between EMdaPriorityMin and |
aPref | The Priority Preference - an additional audio policy parameter. The suggested default is |
Capability | |
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UserEnvironment |
IMPORT_C void | Open | ( | TMdaPackage * | aSettings | ) |
Opens an input audio stream package.
The MMdaAudioInputStreamCallback::MaisOpenComplete() callback function is called when the stream has been
opened and is ready to record data. If the open was unsuccessful, this is indicated by the aError parameter
of the callback.
Parameters | |
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aSettings | A pointer to an TMdaPackage object. |
IMPORT_C const TTimeIntervalMicroSeconds & | Position | ( | ) |
Returns the current position within the data stream in microseconds since the start of streaming.
IMPORT_C void | ReadL | ( | TDes8 & | aData | ) |
Records streaming raw audio data.
If this is the first ReadL() after a successful Open() this function starts the audio recording process.
The MMdaAudioInputStreamCallback::MaisBufferCopied() callback function is called when the buffer has been successfully
filled. A pointer to the newly filled buffer is returned in the callback.
Note: The MMdaAudioInputStreamCallback::MaisBufferCopied() callback function is also called when a Stop() is issued, with a
pointer to the remaining recorded audio data and the aError parameter of the callback set to indicate recording has finished.
Parameters | |
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aData | A reference to a buffer to be written into. |
IMPORT_C void | RequestStop | ( | ) |
Requests a Stop of the recording process.
The device is requested to Stop and does so after all unprocessed buffers are processed and passed
back to the input stream. The device is actually Stopped when the final empty buffer indicating
buffer process completion is received.
See also: CMdaAudioInputStream::Stop()
Sets the sample rate and number of audio channels.
Parameters | |
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aSampleRate | The new sample rate. For possible values, see the TAudioCaps enum in class TMdaAudioDataSettings. |
aChannels | The new number of channels. For possible values, see the TAudioCaps enum in class TMdaAudioDataSettings. |
IMPORT_C void | SetBalanceL | ( | TInt | aBalance = KMMFBalanceCenter | ) |
Sets the current audio balance.
The balance can be any value between KMMFBalanceMaxLeft and KMMFBalanceMaxRight, the default value
being KMMFBalanceCenter.
Parameters | |
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aBalance | A specified balance value. |
IMPORT_C void | SetBitRateL | ( | TInt | aBitRate | ) |
Sets the bit rate to a new value.
Parameters | |
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aBitRate | The new bit rate, in bits per second. |
Leave Codes | |
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KErrNotSupported |
IMPORT_C void | SetDataTypeL | ( | TFourCC | aAudioType | ) |
Sets the data type. If the data type is not explicitly set it will assumed to be pcm16.
If it is set then the hardware must support the data type being set otherwise the
function leaves with KErrNotSupported.
Parameters | |
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aAudioType | The fourCC code used to request the data type of the recorded data. |
Leave Codes | |
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KErrNotSupported |
Sets the audio priority values.
This function cannot be used while the stream object is open. It is intended for use before an Open()
is issued, or between a previous Stop() and a new Open().
See also: CMdaAudioInputStream::NewL()
Parameters | |
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aPriority | The Priority Value. |
aPref | The Priority Preference. |
IMPORT_C void | SetSingleBufferMode | ( | TBool | aSingleMode | ) |
Indicates that the client wishes to use a single buffer to collect the data.
This buffer is passed via the ReadL api.
buffer, EFalse to indicate use of multiple buffers.
Parameters | |
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aSingleMode | ETrue to indicate setting of single buffer mode and the use of a single |
IMPORT_C void | Stop | ( | ) |
Stops the recording process.
The MMdaAudioInputStreamCallback::MaisRecordComplete() callback function is called when recording has been halted. Just prior
to issuing this callback, the FIFO buffers are read and the remaining audio data passed back by a final
MMdaAudioInputStreamCallback::MaisBufferCopied() callback with its aError parameter set to KErrAbort.
Any remaining FIFO buffers are also passed back, with their aError parameter set to KErrAbort.
Stop is immediate and best used for premature stops, for example within destructors.
If it is critical to receive all data buffers upto the point that Recording has Stopped,
we recommend using RequestStop instead. Otherwise some trailing buffers may be lost from the recording process.
If a Stop is issued after a RequestStop, Stop will take precedent.
See also: CMdaAudioInputStream::RequestStop()