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MseqInquire

BoardSupported
Host SystemYes
V4L2Yes
Clarity UHDYes
Concord PoENo
GenTLYes
GevIQYes
GigE VisionYes
IndioNo
Iris GTXYes
Radient eV-CLYes
Rapixo CLYes
Rapixo CoFYes
Rapixo CXPYes
USB3 VisionYes

Inquire information about a sequence context or an individual source or destination setting.

Syntax

AIL_INT MseqInquire(
AIL_ID ContextSeqId, //in
AIL_INT SequenceIndex, //in
AIL_INT64 InquireType, //in
void * UserVarPtr //out
)

Description

This function inquires information about a sequence context or an individual source or destination setting.

Parameters

ContextSeqId (in, AIL_ID)

Specifies the sequence context about which to inquire information. The sequence context must have been previously allocated using MseqAlloc.

SequenceIndex (in, AIL_INT)

Specifies that the sequence context, the source of an input, or a destination of an output is inquired. Set this parameter to one of the following values:

For specifying a context, or an individual source or destination

ValueDescription
M_DEFAULT
M_SEQ_INPUTSpecifies an input of the sequence operation, whose source must be inquired.
M_SEQ_OUTPUTSpecifies an output of the sequence operation, whose destination must be inquired. An output can have multiple destinations.
M_CONTEXT (default)Inquires information about the specified sequence context.

For specifying the index of the destination of the output to inquire

ValueDescription
M_SEQ_DESTSpecifies the destination of the output to inquire.

InquireType (in, AIL_INT64)

Specifies the type of setting about which to inquire.

UserVarPtr *(out, void)

Specifies the address in which to write the requested information. Since the MseqInquire function also returns the requested information, you can set this parameter to M_NULL, except when the specified InquireType requires the UserVarPtr parameter to be set to the address of an AIL_INT,AIL_DOUBLE, or AIL_TEXT_CHAR. In this case, you must set this parameter to the address of an AIL_INT,AIL_DOUBLE, or AIL_TEXT_CHAR, respectively.

Parameter Associations

For retrieving information about the H.264 compression operation settings

The following inquire types allow you to inquire the H.264 compression settings for the sequence context (M_CONTEXT).


M_CODEC_TYPE

Inquires the type of codec used for the compression or decompression operation.

ValueDescription
M_QSV + M_HARDWARESpecifies to perform the operation using hardware acceleration.
M_QSV + M_SOFTWARESpecifies to perform the operation in software.

M_SETTING_AUTO_ADJUSTMENT

Inquires whether incompatible operation settings are automatically adjusted.

ValueDescription
M_DEFAULT
M_DISABLE (default)Specifies to not automatically adjust incompatible settings.
M_ENABLESpecifies to automatically adjust incompatible settings.

M_SIZE_X

Inquires the width of the elementary video stream.

ValueDescription
ValueSpecifies the width, in pixels.

M_SIZE_Y

Inquires the height of the elementary video stream.

ValueDescription
ValueSpecifies the height, in pixels.

M_STREAM_BIT_RATE

Inquires the elementary video stream bit rate.

ValueDescription
M_DEFAULT
Value > 0 (default)Specifies the bit rate, in Kbits/sec.

M_STREAM_BIT_RATE_MAX

Inquires the maximum bit rate that the elementary video stream can have.

ValueDescription
M_DEFAULT
Value > 0 (default)Specifies the maximum bit rate, in Kbits/sec.

M_STREAM_BIT_RATE_MODE

Inquires the type of bit rate the elementary video stream will have.

ValueDescription
M_DEFAULT
M_CONSTANTSpecifies that the bit rate will remain constant throughout the duration of the elementary video stream.
M_VARIABLE (default)Specifies that the bit rate will fluctuate depending on how compressible sections of the elementary video stream are.

M_STREAM_FRAME_RATE

Inquires the frame rate of the elementary video stream.

ValueDescription
M_DEFAULT
Value > 0.0 (default)Specifies the elementary video stream's frame rate, in frames/sec.

M_STREAM_FRAME_RATE_MODE

Inquires how the decoding frame rate, written in the header of M_FILE destination types, is established.

ValueDescription
M_DEFAULT
M_CONSTANT (default)Specifies that the decoding frame rate written in the header of M_FILE destination types is the same as the frame rate specified with M_STREAM_FRAME_RATE.
M_VARIABLESpecifies that the decoding frame rate written in the header of M_FILE destination types is the average encoding frame rate, if the processor could not encode at the specified frame rate; otherwise, the frame rate specified with M_STREAM_FRAME_RATE will be written.

M_STREAM_GROUP_OF_PICTURE_SIZE

Inquires the group-of-pictures size.

ValueDescription
M_DEFAULT
Value (default)Specifies the group-of-pictures size, in number of frames/group.

M_STREAM_LEVEL

Inquires the H.264 compression level used by the compression operation.

ValueDescription
M_DEFAULT
M_LEVEL_1Specifies the 1 compression level.
M_LEVEL_1_1Specifies the 1.1 compression level.
M_LEVEL_1_2Specifies the 1.2 compression level.
M_LEVEL_1_3Specifies the 1.3 compression level.
M_LEVEL_1BSpecifies the 1B compression level.
M_LEVEL_2Specifies the 2 compression level.
M_LEVEL_2_1Specifies the 2.1 compression level.
M_LEVEL_2_2Specifies the 2.2 compression level.
M_LEVEL_3Specifies the 3 compression level.
M_LEVEL_3_1Specifies the 3.1 compression level.
M_LEVEL_3_2Specifies the 3.2 compression level.
M_LEVEL_4Specifies the 4 compression level.
M_LEVEL_4_1Specifies the 4.1 compression level.
M_LEVEL_4_2 (default)Specifies the 4.2 compression level.
M_LEVEL_5Specifies the 5 compression level.
M_LEVEL_5_1Specifies the 5.1 compression level.
M_LEVEL_5_2Specifies the 5.2 compression level.

M_STREAM_PROFILE

Inquires the H.264 compression profile.

ValueDescription
M_DEFAULT
M_PROFILE_BASELINESpecifies to use the baseline profile.
M_PROFILE_HIGH (default)Specifies to use the high profile.
M_PROFILE_MAINSpecifies to use the main profile.

M_STREAM_QUALITY

Inquires the H.264 compression operation priority.

ValueDescription
M_DEFAULT
0 <= Value <= 100 (default)Specifies the speed/quality priority.

Combination Constants — For inquiring the actual values used

Optional.

Usage: You can add one of the following values to the above-mentioned values to get the actual values used if MseqControl with M_SETTING_AUTO_ADJUSTMENT was set to M_ENABLE.

ValueDescription
M_EFFECTIVE_VALUEInquires the actual value used by the compression operation.

For retrieving information about general individual source or destination settings

You can inquire information about the following settings for any type of individual source (M_SEQ_INPUT()) or destination (M_SEQ_OUTPUT()+M_SEQ_DEST()).


M_TYPE

Inquires the type of source or destination at the specified index.

ValueDescription
"FileName"Specifies the drive, directory, and name of the file (for example, "C:\mydirectory\myfile").
M_FILE_FORMAT_AVISpecifies that the file is in AVI format.
M_FILE_FORMAT_H264Specifies that the file is in H.264 elementary video data format.
M_FILE_FORMAT_MP4Specifies that the file is in MP4 format.

For retrieving information about individual file (

You can inquire information about the following settings for individual file sources or destinations (M_SEQ_INPUT() or M_SEQ_OUTPUT()+M_SEQ_DEST() defined as M_FILE).


M_FILE_FORMAT

Inquires the format of the file at the specified index.

ValueDescription
M_FILE_FORMAT_AVISpecifies that the file is in AVI format.
M_FILE_FORMAT_H264Specifies that the file is in H.264 elementary video data format.
M_FILE_FORMAT_MP4Specifies that the file is in MP4 format.

M_STREAM_FILE_NAME

Inquires the name of the file at the specified index.

ValueDescription
ValueSpecifies the file name.

Combination Constants — For getting the string size

Optional.

Usage: You can add one of the following values to the above-mentioned values to get the string's length.

M_STRING_SIZE

Retrieves the length of the string, including the terminating null character ("\0").

Return Value

Type: AIL_INT

The returned value is the requested information, cast to an AIL_INT. If the requested information does not fit into an AIL_INT, this function will return M_NULLor truncate the information.

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