OpalVideoTranscoder Class Reference

#include <vidcodec.h>

Inheritance diagram for OpalVideoTranscoder:

OpalTranscoder OpalMediaFormatPair OpalRFC4175Transcoder OpalRFC4175Decoder OpalRFC4175Encoder Opal_RFC4175RGB_to_RGB24 Opal_RFC4175YCbCr420_to_YUV420P Opal_RGB24_to_RFC4175RGB Opal_YUV420P_to_RFC4175YCbCr420 List of all members.

Public Types

typedef PluginCodec_Video_FrameHeader FrameHeader

Public Member Functions

Operations
virtual bool UpdateMediaFormats (const OpalMediaFormat &inputMediaFormat, const OpalMediaFormat &outputMediaFormat)
virtual PINDEX GetOptimalDataFrameSize (PBoolean input) const
virtual PBoolean ExecuteCommand (const OpalMediaCommand &command)
virtual PBoolean Convert (const RTP_DataFrame &input, RTP_DataFrame &output)

Protected Attributes

PINDEX inDataSize
PINDEX outDataSize
bool forceIFrame

Detailed Description

This class defines a transcoder implementation class that will encode/decode video.

An application may create a descendent off this class and override functions as required for descibing a specific transcoder.


Member Typedef Documentation

typedef PluginCodec_Video_FrameHeader OpalVideoTranscoder::FrameHeader


Constructor & Destructor Documentation

OpalVideoTranscoder::OpalVideoTranscoder ( const OpalMediaFormat inputMediaFormat,
const OpalMediaFormat outputMediaFormat 
)

Create a new video transcoder implementation.

Parameters:
inputMediaFormat  Input media format
outputMediaFormat  Output media format

OpalVideoTranscoder::OpalVideoTranscoder ( const OpalMediaFormat inputMediaFormat,
const OpalMediaFormat outputMediaFormat 
)

Create a new video transcoder implementation.

Parameters:
inputMediaFormat  Input media format
outputMediaFormat  Output media format


Member Function Documentation

virtual bool OpalVideoTranscoder::UpdateMediaFormats ( const OpalMediaFormat inputMediaFormat,
const OpalMediaFormat outputMediaFormat 
) [virtual]

Update the input and output media formats. This can be used to adjust the parameters of a codec at run time. Note you cannot change the basic media format, eg change GSM0610 to G.711, only options for that format, eg 6k3 mode to 5k3 mode in G.723.1.

If a format is empty (invalid) it is ignored and does not update the internal variable. In this way only the input or output side can be updated.

The default behaviour updates the inputMediaFormat and outputMediaFormat member variables.

Parameters:
inputMediaFormat  Input media format
outputMediaFormat  Output media format

Reimplemented from OpalTranscoder.

virtual PINDEX OpalVideoTranscoder::GetOptimalDataFrameSize ( PBoolean  input  )  const [virtual]

Get the optimal size for data frames to be converted. This function returns the size of frames that will be most efficient in conversion. A RTP_DataFrame will attempt to provide or use data in multiples of this size. Note that it may not do so, so the transcoder must be able to handle any sized packets.

Parameters:
input  Flag for input or output data size

Implements OpalTranscoder.

virtual PBoolean OpalVideoTranscoder::ExecuteCommand ( const OpalMediaCommand command  )  [virtual]

Execute the command specified to the transcoder. The commands are highly context sensitive, for example VideoFastUpdate would only apply to a video transcoder.

The default behaviour checks for a OpalVideoUpdatePicture and sets the updatePicture member variable if that is the command.

Parameters:
command  Command to execute.

Reimplemented from OpalTranscoder.

virtual PBoolean OpalVideoTranscoder::Convert ( const RTP_DataFrame input,
RTP_DataFrame output 
) [virtual]

Convert the data from one format to another. This function takes the input data as a RTP_DataFrame and converts it to its output format, placing it into the RTP_DataFrame provided.

This is a dummy function as nearly all video conversion will does not have a one to one input to output frames ratio, so the ConvertFrames() function is used instead.

Returns PFalse if the conversion fails.

Parameters:
input  Input data
output  Output data

Implements OpalTranscoder.


Member Data Documentation

PINDEX OpalVideoTranscoder::inDataSize [protected]

PINDEX OpalVideoTranscoder::outDataSize [protected]

bool OpalVideoTranscoder::forceIFrame [protected]


The documentation for this class was generated from the following file:
Generated on Fri Mar 7 07:37:03 2008 for OPAL by  doxygen 1.5.1