ILMMpg2MxT Interface

This is the interface for the LEAD MPEG2 Transport Multiplexer.

Interface Properties:

Interface Methods:

HRESULT ClosePrivateData();

Description

Informs the multiplexer that the application will not be providing any more private data. This will allow the multiplexer to properly close the output stream. This method is not required if the AutoClosePrivateData property is set to VARIANT_TRUE.

Returns

S_OK if successful, < 0 if an error occurred.

HRESULT GetPrivateDataFormatInfo(VARIANT* pInfo);

Parameters

Description

Retrieves the information set with SetPrivateFormatInfo.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

E_POINTER                  [0x80004003] pInfo is NULL

HRESULT SetPrivateDataFormatInfo(VARIANT Info, long InfoLength);

Parameters

Description

Sets the user-specified private format information. It is used as the additional identification information in the registration descriptor. By default, no additional information is written.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

E_INVALIDARG              [0x80070057] pInfo is not a byte array variant

HRESULT WritePrivateData(long Flags, double PTS, VARIANT Data, long DataLength);

Parameters

Description

Writes the application-provided data to multiplexer output.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

E_INVALIDARG              [0x80070057] Data is not a byte array variant

HRESULT ConvertDateToPrecisionTimeStamp(BSTR pszDateString, BSTR pszFormatString, double *pPrecisionTimeStampValue);

Parameters

Description

Use this method to convert a string containing the date and time to a number representing microseconds since Jan 1, 1970. This value can be then used to set the PrecisionTimeStampStartValue property.

See the Precision Time Stamps topic for more information on precision time stamps and the format of the strings that can be converted.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes:

E_INVALIDARG                  [0x80070057] pszDateString or pszFormatString is invalid

HRESULT ResetToDefaultsEx(Mpg2MxT_APILEVEL ApiLevel);

Parameters

Description

Call this method to ensure future versions of the multiplexer will use the same defaults as the current version. Call this method before calling any other method in this interface.

If you do not call this method, the multiplexer will use the defaults that were last set by the user in the property page.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

N/A

HRESULT GetStreamCount(Mpg2MxT_StreamType streamType, long *pVal);

Parameters

Description

Use this method to count of the number of streams of a certain type (Audio, Video, Metadata, Other). Valid values for streamType are any member of Mpg2MxT_StreamType enumeration except Mpg2MxT_StreamType_ProgramMap.

Note: Build the graph before calling this method because the method counts connected input pins.

This method does not count any private data stream added with EnablePrivateData. It only counts the streams from the input file being written to the output file.

Use the number of streams returned by this function to know which values to pass to the GetStreamPID/SetStreamPID methods.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

E_POINTER                  [0x80004003] pVal is NULL

HRESULT GetStreamType(long streamIndex, Mpg2MxT_StreamType *pVal);

Parameters

Description

Use this method to find out the type of a particular stream. The streamIndex must be between 0 and the total number of streams being written to the file minus 1.

Note: Build the graph before calling this method because the method counts connected input pins.

This method does not count any private data stream added with EnablePrivateData. It only counts the streams from the input file being written to the output file.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

HRESULT SetPreferredStreamPID(long streamIndex, long newVal);

Parameters

Description

Use this method to set the preferred stream PID for the stream indicated by streamIndex. Setting the stream PID to -1 allows the mux to pick the appropriate PID for each stream.

streamIndex can identify a generic stream, a video stream, audio stream, etc. The following values are possible:

In most cases, there will be one audio and one video stream. So the following pseudo-code will set the PIDs for program map, audio, video and KLV metadata streams:

pMpgDmx->SetPreferredStreamPID(Mpg2MxT_StreamType_ProgramMap, 0x20);
pMpgDmx->SetPreferredStreamPID(Mpg2MxT_StreamType_Video, 0x30);
pMpgDmx->SetPreferredStreamPID(Mpg2MxT_StreamType_Audio, 0x40);
pMpgDmx->SetPreferredStreamPID(Mpg2MxT_StreamType_Metadata_KLV, 0x50);

When using this method to set a PID for each stream, be sure each PID is unique. Otherwise, the multiplexer could pick a different PID for this stream if it conflicts with another stream.

The PID is the number between 0 and 0x1FFF used to identify an elementary in the MPEG2 Transport stream. See the ISO ISO/IEC 13818-1 MPEG-2 Transport specification for more details on this value. The values between 0 and 15 and 0x1FFF are reserved, so you cannot use them.

This method does not affect any private data stream added with EnablePrivateData. It only affects the streams from the input file being written to the output file. To set the PID of the private data stream, use the PrivateDataPID property.

Note: Build the graph before calling this method because the method affects only connected input pins.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

HRESULT GetPreferredStreamPID(long streamIndex, long *pVal);

Parameters

Description

Use this method to get the preferred stream PID for the stream indicated by streamIndex. See the SetPreferredStreamPID method for a description of the possible values for streamIndex.

By default, the preferred stream PID value is -1, which lets the mux pick the stream PID.

Note: Build the graph before calling this method because the method counts connected input pins.

The PID is the number between 0 and 0x1FFF used to identify an elementary in the MPEG2 Transport stream. See the ISO ISO/IEC 13818-1 MPEG-2 Transport specification for more details on this value.

This method does not count any private data stream added with EnablePrivateData. It only counts the streams from the input file being written to the output file. To get the PID of the private data stream, use the PrivateDataPID property.

Returns

S_OK if successful, < 0 if an error occurred.

Common Error Codes

Data types:

Flags being passed to the WritePrivateData method:

typedef enum Mpg2MxT_WriteFlag 
{ 
   Mpg2MxT_WriteFlag_PTSValid = 0x00000001,              /* The PTS value is valid */ 
   Mpg2MxT_WriteFlag_PTSInSeconds = 0x00000002,          /* The PTS value is specified in seconds */ 
   Mpg2MxT_WriteFlag_UseStreamPTS = 0x00000004,          /* The current stream time should be used instead of the provided PTS */ 
   Mpg2MxT_WriteFlag_SyncPoint = 0x00000008,             /* The data is a synchronization point, and is seekable */ 
   Mpg2MxT_WriteFlag_Discontinuity = 0x00000010,         /* reserved */ 
} Mpg2MxT_WriteFlags; 

Flags being passed to the OutputType property:

typedef enum Mpg2MxT_OutputType 
{ 
   Mpg2MxT_OutputType_Default = 0x00000000,              /* Default output mode (non-broadcast) */ 
   Mpg2MxT_OutputType_Broadcast = 0x00000001,            /* Broadcast mode */ 
   Mpg2MxT_OutputType_HLS = 0x00000002,                   /* HTTP Live Streaming */ 
   Mpg2MxT_OutputType_Mode = 0x0000000F,               /* Internal use - the mode covers the lower 4 bits, all are mutually exclusive */ 
   Mpg2MxT_OutputType_UsePadding = 0x00000010,           /* Use padding to achieve constant bitrate */ 
   Mpg2MxT_OutputType_AsynchronousMetadata = 0x00000000, /* Write metadata using Asynchronous streams */ 
   Mpg2MxT_OutputType_SynchronousMetadata = 0x00000020,  /* Write metadata using Synchronous streams */ 
   Mpg2MxT_OutputType_LowLatency = 0x00000040,  /* Low latency mode (each sample is sent to the sink without buffering) */ 
   Mpg2MxT_OutputType_FullyMultiplexMetadata = 0x00000080, /* Force the multiplexer to wait for metadata, supplied through the input pin, so that the output can be fully multiplexed with the other streams */ 
   Mpg2MxT_OutputType_ModeMax = 0x00000002,           /* Internal use - Set this to the maximum mode value */ 
   Mpg2MxT_OutputType_ValidFlags = 0x000000FF,           /* Internal use - Change this whenever new OutputType flags are added */ 
} Mpg2MxT_OutputType; 

Possible values passed to ResetToDefaultsEx:

typedef enum Mpg2MxT_APILEVEL 
{ 
   Mpg2MxT_APILEVEL_1 = 0, 
} Mpg2MxT_APILEVEL; 

Possible values for the PrecisionTimeStampAction property:

typedef enum 
{ 
   Mpg2MxT_PrecisionTimeStampAction_Ignore = 0, /* Do nothing - the timestamps will be written in the output file if they are present in the compressed stream */ 
   Mpg2MxT_PrecisionTimeStampAction_RemoveExisting = 1, /* Do not write any precision time stamps. Remove them if they are present in the compressed stream */ 
   Mpg2MxT_PrecisionTimeStampAction_AddIfMissing = 2, /* Add the precision time stamps only if they are not present in the compressed stream. If the compressed stream contains precision time stamps already, leave them in the stream */ 
   Mpg2MxT_PrecisionTimeStampAction_AddAlways = 3 /* Always write the precision time stamps. If the compressed stream contains time stamps, overwrite them. If the compressed stream does not contain them, add them */ 
} Mpg2MxT_PrecisionTimeStampAction; 

Enumeration used by GetStreamCount, GetStreamType, SetPreferredStreamPID and GetPreferredStreamPID methods to specify stream types:

typedef enum 
{ 
   Mpg2MxT_StreamType_ProgramMap = -1, 
   Mpg2MxT_StreamType_Any = 0, /* all the streams */ 
   Mpg2MxT_StreamType_Video = 0x80, 
   Mpg2MxT_StreamType_Audio = 0xA0, 
   Mpg2MxT_StreamType_Metadata_KLV = 0xC0, 
   Mpg2MxT_StreamType_Metadata_Other = 0xE0, 
   Mpg2MxT_StreamType_Other = 0x100 
} Mpg2MxT_StreamType; 

Possible values for the Throttle property:

typedef enum 
{ 
   Mpg2MxT_Throttle_Disabled = 0, /* Disable all output throttling */ 
   Mpg2MxT_Throttle_Automatic = 1, /* Automatically apply throttling to recognized output sinks. This is the default value. */ 
   Mpg2MxT_Throttle_Enabled = 2 /* Force output throttling */ 
} Mpg2MxT_Throttle; 

Note 1: Possible values for the OutputType property

The OutputType property can be set to a bitwise OR of at most one flag from each of the following categories. You cannot OR two flags from the same category:

Example 1. To generate non-broadcast streams with Synchronous metadata and no padding, set OutputType to the following value:

Mpg2MxT_OutputType_Default | Mpg2MxT_OutputType_SynchronousMetadata

Example 2. To generate broadcast streams with padding, set OutputType to the following value:

Mpg2MxT_OutputType_Broadcast | Mpg2MxT_OutputType_Padding