Microsoft DirectX 8.0

ILocator Interface

The ILocator base class interface is implemented (through its derived interfaces such as IATSCLocator) on Locator objects that contain information about the tuning space. Locator objects are generally used by the Network Provider filter to help a tuner find and acquire the transport stream. Applications do not use Locator objects except possibly for debugging purposes. All Locator objects also support IPersistPropertyBag.

MethodNameDescription
CloneCreates a copy of the Locator.
get_CarrierFrequencyRetrieves the frequency of the RF signal.
get_InnerFECRetrieves the type of inner forward error correction that is used.
get_InnerFECRateRetrieves the inner FEC rate.
get_ModulationRetrieves the modulation type.
get_OuterFECRetrieves the type of outer forward error correction that is used.
get_OuterFECRateSets the outer FEC rate.
get_SymbolRateGets the QPSK symbol rate.
put_CarrierFrequencySets the frequency of the RF signal.
put_InnerFECSets the type of inner forward error correction that is used.
put_InnerFECRateSets the inner FEC rate.
put_ModulationSets the modulation type.
put_OuterFECSets the type of inner forward error correction that is used.
put_OuterFECRateSets the outer FEC rate.
put_SymbolRateSets the QPSK symbol rate.

ILocator::Clone

ILocator Interface

Creates a copy of the Locator.

Syntax

HRESULT Clone(
    ILocator **NewLocator
    );

Parameters

NewLocator
[out, retval] Address of an ILocator interface pointer that will receive the returned interface.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::get_CarrierFrequency

ILocator Interface

Retrieves the frequency of the RF signal.

Syntax

HRESULT get_CarrierFrequency(
    long* Frequency
    );

Parameters

Frequency
[out, retval] Pointer to a variable of type long that receives the frequency value.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::get_InnerFEC

ILocator Interface

Retrieves the type of forward error correction that is used.

Syntax

HRESULT get_InnerFEC(
    FECMethod* FEC
    );

Parameters

FEC
[out, retval] Pointer to a variable of type FECMethod that receives the inner forward FEC.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

FECMethod is defined in bdatypes.h as follows:
typedef enum FECMethod {
    BDA_FEC_METHOD_NOT_SET = -1,
    BDA_FEC_METHOD_NOT_DEFINED = 0,
    BDA_FEC_VITERBI = 1,          // FEC is a Viterbi Binary Convolution.
    BDA_FEC_RS_204_188,       // The FEC is Reed-Solomon 204/188 (outer FEC)
    BDA_FEC_MAX,
} FECMethod;

ILocator::get_InnerFECRate

ILocator Interface

Retrieves the inner FEC rate.

Syntax

HRESULT get_InnerFECRate(
    BinaryConvolutionCodeRate* FEC
    );

Parameters

FEC
[out, retval] Pointer to a variable of type BinaryConvolutionCodeRate that receives the inner FEC rate.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

BinaryConvolutionCodeRate is defined in bdatypes.h as follows:

typedef enum {
    BDA_BCC_RATE_NOT_SET = -1,
    BDA_BCC_RATE_NOT_DEFINED = 0,
    BDA_BCC_RATE_1_2 = 1,
    BDA_BCC_RATE_2_3 = 2,
    BDA_BCC_RATE_3_4 = 3,
    BDA_BCC_RATE_3_5 = 4,
    BDA_BCC_RATE_4_5 = 5,
    BDA_BCC_RATE_5_6 = 6,
    BDA_BCC_RATE_5_11 = 7,
    BDA_BCC_RATE_7_8 = 8,
    BDA_BCC_RATE_MAX = 9
} BinaryConvolutionCodeRate;

ILocator::get_Modulation

ILocator Interface

Retrieves the modulation type.

Syntax

HRESULT get_Modulation(
    ModulationType* Modulation
    );

Parameters

Modulation
[out, retval] Pointer that receives the new modulation type.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

See put_Modulation for the definition of ModulationType.

ILocator::get_OuterFEC

ILocator Interface

Retrieves the type of outer forward error correction that is used.

Syntax

HRESULT get_OuterFEC(
    FECMethod* FEC
    );

Parameters

FEC
[out, retval] Pointer to a variable of type FECMethod that receives the outer forward FEC.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

See get_InnerFEC for the definition of FECMethod.

ILocator::get_OuterFECRate

ILocator Interface

Retrieves the outer FEC rate.

Syntax

HRESULT get_OuterFECRate(
    BinaryConvolutionCodeRate* FEC
    );

Parameters

FEC
[out, retval] Pointer to a variable of type BinaryConvolutionCodeRate that receives the outer FEC rate.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::get_SymbolRate

ILocator Interface

Retrieves the QPSK symbol rate.

Syntax

HRESULT get_SymbolRate(
    long* Rate
    );

Parameters

Rate
[out, retval] Pointer to a variable of type long that receives the QPSK symbol rate.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

QPSK modulates symbols onto the RF signal. These symbols are detected by the demodulator and used to reconstruct a bit stream. QPSK allows the rate at which symbols are (de)modulated to be changed.

ILocator::put_CarrierFrequency

ILocator Interface

Sets the frequency of the RF signal.

Syntax

HRESULT put_CarrierFrequency(
    long Frequency
    );

Parameters

Frequency
[in] Variable of type long that specifies the frequency value.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::put_InnerFEC

ILocator Interface

Sets the type of inner forward error correction that is used.

Syntax

HRESULT put_InnerFEC(
    FECMethod FEC
    );

Parameters

FEC
[in] Variable of type FECMethod that specifies the inner FEC.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::put_InnerFECRate

ILocator Interface

Sets the inner FEC rate.

Syntax

HRESULT put_InnerFECRate(
    BinaryConvolutionCodeRate FEC
    );

Parameters

FEC
[in] Variable of type BinaryConvolutionCodeRate that specifies the inner FEC rate.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::put_Modulation

ILocator Interface

Sets the modulation type.

Syntax

HRESULT put_Modulation(
    ModulationType Modulation
    );

Parameters

Modulation
[in] Specifies the modulation type.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

The ModulationType enum is defined in bdatypes.h as follows:
typedef enum {
    BDA_MOD_NOT_SET = -1,
    BDA_MOD_NOT_DEFINED = 0,
    BDA_MOD_16QAM = 1,
    BDA_MOD_32QAM = 2,
    BDA_MOD_64QAM = 3,
    BDA_MOD_80QAM = 4,
    BDA_MOD_96QAM = 5,
    BDA_MOD_112QAM = 6,
    BDA_MOD_128QAM = 7,
    BDA_MOD_160QAM = 8,
    BDA_MOD_192QAM = 9,
    BDA_MOD_224QAM = 10,
    BDA_MOD_256QAM = 11,
    BDA_MOD_320QAM = 12,
    BDA_MOD_384QAM = 13,
    BDA_MOD_448QAM = 14,
    BDA_MOD_512QAM = 15,
    BDA_MOD_640QAM = 16,
    BDA_MOD_768QAM = 17,
    BDA_MOD_896QAM = 18,
    BDA_MOD_1024QAM = 19,
    BDA_MOD_QPSK = 20,
    BDA_MOD_BPSK = 21,
    BDA_MOD_OQPSK = 22,
    BDA_MOD_8VSB = 23,
    BDA_MOD_16VSB = 24,
    BDA_MOD_ANALOG_AMPLITUDE = 25,
    BDA_MOD_ANALOG_FREQUENCY = 26,
    BDA_MOD_MAX = 27
} ModulationType;

ILocator::put_OuterFEC

ILocator Interface

Sets the type of outer forward error correction that is used.

Syntax

HRESULT put_OuterFEC(
    FECMethod FEC
    );

Parameters

FEC
[in] Variable of type FECMethod that specifies the outer forward error correction.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

ILocator::put_OuterFECRate

ILocator Interface

Sets the outer FEC rate.

Syntax

HRESULT put_OuterFECRate(
    BinaryConvolutionCodeRate FEC
    );

Parameters

FEC
[in] Variable of type BinaryConvolutionCodeRate that specifies the outer FEC rate.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

BinaryConvolutionCodeRate is defined in bdatypes.h as follows:
typedef enum {
    BDA_BCC_RATE_NOT_SET = -1,
    BDA_BCC_RATE_NOT_DEFINED = 0,
    BDA_BCC_RATE_1_2 = 1,
    BDA_BCC_RATE_2_3 = 2,
    BDA_BCC_RATE_3_4 = 3,
    BDA_BCC_RATE_3_5 = 4,
    BDA_BCC_RATE_4_5 = 5,
    BDA_BCC_RATE_5_6 = 6,
    BDA_BCC_RATE_5_11 = 7,
    BDA_BCC_RATE_7_8 = 8,
    BDA_BCC_RATE_MAX = 9
} BinaryConvolutionCodeRate;

ILocator::put_SymbolRate

ILocator Interface

Sets the QPSK symbol rate.

Syntax

HRESULT put_SymbolRate(
    long Rate
    );

Parameters

Rate
[in] Variable of type long that specifies the QPSK symbol rate.

Return Value

Returns S_OK if successful. If the method fails, error information can be retrieved using the standard COM IErrorInfo interface.

Remarks

QPSK modulates symbols onto the RF signal. These symbols are detected by the demodulator and used to reconstruct a bit stream. QPSK allows the rate at which symbols are (de)modulated to be changed.