Codec Toolkit Reference

This documentation page is deprecated since OpenViBE 0.12.0 (oct 2011), and won't be maintained. The new page can be found here .

This reference page is divided in the following sections :

• Introduction

The superclass :

• Codec

And its subclasses for the two subtypes of codec :

• Decoder
• Encoder

And their subclasses for each stream codec :

• Streamed Matrix Decoder
  • Signal Decoder
  • Feature Vector Decoder
  • Spectrum Decoder
  • Channel Localisation Decoder
• Stimulation Decoder
• Experiment Information Decoder

• Streamed Matrix Encoder
  • Signal Encoder
  • Feature Vector Encoder
  • Spectrum Encoder
  • Channel Localisation Encoder
• Stimulation Encoder
• Experiment Information Encoder

Introduction

All codecs share the same behaviour when it comes to construction and destruction. Be sure to always initialize a codec before use, and never leave an uninitialized codec at stop. Here is what you can expect when manipulating codec objects :

• Default constructor : the codec is declared, but not initialized.
• TSpecificCodecClass(T& rBoxAlgorithm) : the codec is declared and initialized.
• Destructor : uninitializes the codec
• initialize(T& rBoxAlgorithm) : manually initializes the codec. Does nothing if already initialized.
• uninitialize() : manually uninitializes the codec. Does nothing if already uninitialized.

TCodec

The TCodec < T > class implements the behavior common to all encoders and decoders. The template class T refers to the class of the box in which the codec will work.

Protected Members

• The BoxAlgorithm T

  T* m_pBoxAlgorithm;
  

• The codec algorithm

  OpenViBE::Kernel::IAlgorithmProxy* m_pCodec;
  

Public Methods

• Initialize : sets the reference to the T instance and calls the initialize() method, specific to each codec.

  OpenViBE::boolean initialize(T& rBoxAlgorithm)
  

• Uninitialize : method overwritten specifically by each codec.

  OpenViBE::boolean uninitialize(void)
  

TDecoder

The TDecoder < T > class inherits from TCodec and implements the behavior common to all decoders. The template class T refers to the class of the box in which the codec will work.

Protected Members

• The input memory buffer to be filled with incoming chunks.

  OpenViBE::Kernel::TParameterHandler < const OpenViBE::IMemoryBuffer* > m_pInputMemoryBuffer;
  

Public Methods

• Decode moethod: decode the input chunk on given indexes. Basically, it just sets the input memory buffer, calls process() on the decoder algorithm, and mark the input chunk as deprecated if asked (if nothing specified, by default the chunk is marked).

  OpenViBE::boolean decode(OpenViBE::uint32 ui32InputIndex, OpenViBE::uint32 ui32ChunkIndex, OpenViBE::boolean bMarkInputAsDeprecated = true)
  

• Check methods: tells which type of memory buffer was just decoded. These methods are implemented by all decoders with respect to their own triggers.

  OpenViBE::boolean isHeaderReceived(void)
  OpenViBE::boolean isBufferReceived(void)
  OpenViBE::boolean isEndReceived(void)
  

TEncoder

The TEncoder < T > class inherits from TCodec and implements the behavior common to all encoders. The template class T refers to the class of the box in which the codec will work.

Protected Members

• The output memory buffer to be filled with outgoing chunks.

  OpenViBE::Kernel::TParameterHandler < OpenViBE::IMemoryBuffer* > m_pOutputMemoryBuffer;
  

Public Methods

• Encode : encode the input memory buffer. Basically, it just sets the output memory buffer, calls encodeXXX(). The encodeXXX() methods are specified by each encoder, with respect to their own triggers. The developer has to mark the output as ready to send manually afterward, in order to have accurate timing of the chunks.

  OpenViBE::boolean encodeHeader(OpenViBE::uint32 ui32OutputIndex)
  OpenViBE::boolean encodeBuffer(OpenViBE::uint32 ui32OutputIndex)
  OpenViBE::boolean encodeEnd(OpenViBE::uint32 ui32OutputIndex)
  

TStreamedMatrixDecoder

The Streamed Matrix Decoder is able to process a IMatrix from a Streamed Matrix input chunk. Be aware that you get a reference on the TParameterHandler.

OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getOutputMatrix()

TSignalDecoder

The Signal Decoder inherits from the Streamed Matrix Decoder. It is able to process a IMatrix and a Sampling Frequency from a Signal input chunk. Be aware that you get references on the TParameterHandlers.

// From TStreamedMatrixDecoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getOutputMatrix()
// Signal-specific :
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >& getOutputSamplingRate()

TFeatureVectorDecoder

The Feature Vector Decoder inherits from the Streamed Matrix Decoder. It is able to process a IMatrix with dimension 2 from a Feature Vector input chunk. Be aware that you get a reference on the TParameterHandler.

// From TStreamedMatrixDecoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getOutputMatrix()

TSpectrumDecoder

The Spectrum Decoder inherits from the Streamed Matrix Decoder. It is able to process 2 IMatrix objects (spectrum & Min-Max frequency bands) from a Spectrum input chunk. Be aware that you get references on the TParameterHandlers.

// From TStreamedMatrixDecoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getOutputMatrix()
// Spectrum-specific :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getOutputMinMaxFrequencyBands()

TChannelLocalisationDecoder

The Channel Localisation Decoder inherits from the Streamed Matrix Decoder. It is able to process a IMatrix (Localisation Matrix) and a boolean (Dynamic or not) from a Channel Localisation input chunk. Be aware that you get references on the TParameterHandlers.

// From TStreamedMatrixDecoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getOutputMatrix()
// Channel localisation specific :
OpenViBE::Kernel::TParameterHandler < OpenViBE::boolean >& getOutputDynamic()

TStimulationDecoder

The Stimulations Decoder is able to process a IStimulationSet from a Stimulations input chunk. Be aware that you get a reference on the TParameterHandler.

OpenViBE::Kernel::TParameterHandler < OpenViBE::IStimulationSet* >& getOutputStimulationSet()

TExperimentInformationDecoder

The Experiment Information Decoder is able to process various elements from an Experiment Information input chunk. Be aware that you get references on the TParameterHandlers.

OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getOutputExperimentIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getOutputExperimentDate()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getOutputSubjectIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getOutputSubjectName()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getOutputSubjectAge()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getOutputSubjectGender()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getOutputLaboratoryIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getOutputLaboratoryName()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getOutputTechnicianIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getOutputTechnicianName()

TStreamedMatrixEncoder

The Streamed Matrix Encoder needs a IMatrix in order to process to encoding. As you get a reference you can modify the input directly.

OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getInputMatrix()

TSignalEncoder

The Signal Encoder inherits from the Streamed Matrix Encoder. It needs a IMatrix and a Sampling Frequency in order to process to encoding. As you get a reference you can modify the input directly.

// From TStreamedMatrixEncoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getInputMatrix()
// Signal-specific :
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >& getInputSamplingRate()

TFeatureVectorEncoder

The Feature Vector Encoder inherits from the Streamed Matrix Encoder. It needs a IMatrix (2 dimensions) in order to process to encoding. As you get a reference you can modify the input directly.

// From TStreamedMatrixEncoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getInputMatrix()

TSpectrumEncoder

The Spectrum Encoder inherits from the Streamed Matrix Encoder. It needs 2 IMatrix (spectrum & Min-Max frequency bands) in order to process to encoding. As you get a reference you can modify the input directly.

// From TStreamedMatrixEncoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getInputMatrix()
// Spectrum-specific :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getInputMinMaxFrequencyBands()

TChannelLocalisationEncoder

The Channel Localisation Encoder inherits from the Streamed Matrix Encoder. It needs a IMatrix (Localisation Matrix) and a boolean (Dynamic or not) in order to process to encoding. As you get a reference you can modify the input directly. The Channel Localisation Encoder inherits from the Streamed Matrix Encoder. It needs a IMatrix (Localisation Matrix) and a boolean (Dynamic or not) in order to process to encoding. As you get a reference you can modify the input directly.

// From TStreamedMatrixEncoder <T> :
OpenViBE::Kernel::TParameterHandler < OpenViBE::IMatrix* >& getInputMatrix()
// Channel Localisation specific :
OpenViBE::Kernel::TParameterHandler < OpenViBE::boolean >& getInputDynamic()

TStimulationEncoder

The Stimulations Encoder needs a IStimulationSet in order to process to encoding. As you get a reference you can modify the input directly.

OpenViBE::Kernel::TParameterHandler < OpenViBE::IStimulationSet* >& getInputStimulationSet()

TExperimentInformationEncoder

The Experiment Information Encoder needs various elements in order to process to encoding. As you get a reference you can modify the input directly.

OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getInputExperimentIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getInputExperimentDate()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getInputSubjectIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getInputSubjectName()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getInputSubjectAge()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getInputSubjectGender()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getInputLaboratoryIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getInputLaboratoryName()
OpenViBE::Kernel::TParameterHandler < OpenViBE::uint64 >&   getInputTechnicianIdentifier()
OpenViBE::Kernel::TParameterHandler < OpenViBE::CString* >& getInputTechnicianName()