blue_st_sdk.features.audio.adpcm package

Submodules

blue_st_sdk.features.audio.adpcm.bv_audio_sync_manager module

class blue_st_sdk.features.audio.adpcm.bv_audio_sync_manager.BVAudioSyncManager

Bases: object

The feature contains all mandatory ADPCM synchronization parameters extracted from an AudioSync received packet.

classmethod get_index_in()

Returns the adpcm_index_in parameter value.

Returns:

int: Current adpcm index.

classmethod get_pred_sample_in()

Returns The adpcm_predsample_in parameter value.

Returns:

short: The adpcm predsample actual value.

classmethod initialize_reset_flag()

Initialize reset flag.

classmethod is_intra()

Returns the intra_flag parameter state.

Returns:

boolean: True if is activated, False elsewhere.

classmethod set_synchronization_parameters(sample)

Populate all mandatory adpcm synchronization parameters from an input

FeatureAudioADPCMSync Sample.

Args:

sample (Sample): A Sample exctracted from a received

FeatureAudioADPCMSync synchronization packet (6 bytes).

blue_st_sdk.features.audio.adpcm.feature_audio_adpcm module

class blue_st_sdk.features.audio.adpcm.feature_audio_adpcm.ADPCMEngine

Bases: object

DPCM Engine class. It contains all the operations and parameters necessary to decompress the received audio.

__init__()

Constructor.

decode(code, sync_manager)

ADPCM_Decode.

Args:

code (byte): It contains a 4-bit ADPCM sample.

Returns:

int: A 16-bit ADPCM sample.

class blue_st_sdk.features.audio.adpcm.feature_audio_adpcm.FeatureAudioADPCM(node)

Bases: blue_st_sdk.feature.Feature

The feature handles the compressed audio data acquired from a microphone.

Data is a twenty bytes array.

AUDIO_PACKAGE_SIZE = 40

DATA_LENGTH_BYTES = 20

DATA_MAX = 0

DATA_MIN = 256

FEATURE_DATA_NAME = 'Audio'

FEATURE_FIELDS = <blue_st_sdk.features.field.Field object>

FEATURE_NAME = 'ADPCM Audio'

FEATURE_UNIT = None

__init__(node)

Constructor.

Args:

node (blue_st_sdk.node.Node): Node that will send data to

this feature.

bv_sync_manager = None

engine_adpcm = None

extract_data(timestamp, data, offset)

Extract the data from the feature’s raw data.

Args:

data (bytearray): The data read from the feature (a 20 bytes array). offset (int): Offset where to start reading data (0 by default).

Returns:

blue_st_sdk.feature.ExtractedData: Container of the number of bytes read (20) and the extracted data (audio info, the 40 shorts array).

Raises:

blue_st_sdk.utils.blue_st_exceptions.BlueSTInvalidDataException

if the data array has not enough data to read.

classmethod get_audio(sample)

Get the audio data from a sample.

Args:

sample (blue_st_sdk.feature.Sample): Sample data.

Returns:

short[]: audio values if the data array is valid, None[] otherwise.

set_audio_sync_parameters(sample)

Set the object synchronization parameters necessary to the

decompression process.

Args:

sample (blue_st_sdk.feature.Sample): Extracted sample which

contains the synchronization parameters.

blue_st_sdk.features.audio.adpcm.feature_audio_adpcm_sync module

class blue_st_sdk.features.audio.adpcm.feature_audio_adpcm_sync.FeatureAudioADPCMSync(node)

Bases: blue_st_sdk.feature.Feature

The feature handles the audio synchronization parameters mandatory to the ADPCM audio decompression.

ADPCM_INDEX_INDEX = 0

ADPCM_PREDSAMPLE_INDEX = 1

DATA_LENGTH_BYTES = 6

DATA_MAX = 32767

DATA_MIN = -32768

FEATURE_DATA_NAME = ['ADPCM_index', 'ADPCM_predsample']

FEATURE_INDEX_FIELD = <blue_st_sdk.features.field.Field object>

FEATURE_NAME = 'ADPCM Sync'

FEATURE_PREDSAMPLE_FIELD = <blue_st_sdk.features.field.Field object>

FEATURE_UNIT = None

__init__(node)

Constructor.

Args:

node (blue_st_sdk.node.Node): Node that will send data to

this feature.

extract_data(timestamp, data, offset)

Extract the audio sync data from the feature’s raw data.

In this case it reads a short integer (adpcm_index) and an integer (adpcm_predsample).

Args:

data (bytearray): The data read from the feature (a 6 bytes array). offset (int): Offset where to start reading data (0 by default).

Returns:

blue_st_sdk.feature.ExtractedData: Container of the number of bytes read (6) and the extracted data (audio sync info, a short and an int).

Raises:

blue_st_sdk.utils.blue_st_exceptions.BlueSTInvalidDataException

if the data array has not enough data to read.

static get_index()

Method which extract the index synchronization parameter from a buffer

passed as parameter

Args:

sample (blue_st_sdk.feature.Sample): Sample data (6 bytes).

Returns:

short: The ADPCM index synch parameter if the data array is valid, “None” otherwise.

static get_predicted_sample()

Method which extract the predsample synchronization parameter from a

buffer passed as parameter

Args:

sample (blue_st_sdk.feature.Sample): Sample data (6 bytes).

Returns:

short: The ADPCM predsample synch parameter if the data array is valid, “None” otherwise.

Module contents