MbufInquire()函数

Synopsis

Inquire about a data buffer.

Format

long MbufInquire(BufId, ParamToInquire, UserVarPtr)

MIL_ID BufId;	Source buffer identifier
long InquireType;	Type of information about which to inquire
void *UserVarPtr;	Storage location for requested information

Description

This function inquires about a specified MIL buffer parameter setting. This function is useful, for example, to check the size of a buffer restored from disk.

The BufId parameter specifies the identifier of the source buffer.

The InquireType parameter specifies the buffer parameter about which to inquire. This parameter can be set to one of the following values:

InquireType	Description
M_SIZE_X	Width of the buffer.
M_SIZE_Y	Height of the buffer.
M_SIZE_BAND	Number of buffer color bands.
M_SIZE_BIT	Buffer depth in bits.
M_TYPE	Buffer data type (size in bits + M_SIGNED, M_UNSIGNED, or M_FLOAT).
M_SIGN	Buffer range (M_SIGNED or M_UNSIGNED).
M_ATTRIBUTE	Buffer attribute.
M_OWNER_SYSTEM	Identifier of the system on which the buffer has been allocated
M_PITCH	The number of memory (not data) pixels in each line of the buffer.
M_PITCH_BYTE	The number of memory (not data) bytes in each line of the buffer.
M_HOST_ADDRESS	Host pointer to the buffer or M_NULL. If available, this pointer can be used to directly access the data of a MIL buffer with the Host CPU..
M_PHYSICAL_ADDRESS	Physical address of the Host buffer or M_NULL. Available only for a non-paged buffer mapped on the Host. This type of buffer is used only for access by bus masters other than the Host CPU.
M_PARENT_ID	Identifier of parent buffer. (returns same as BufId if no parent buffer)
M_PARENT_OFFSET_X	X offset in relation to the parent buffer.
M_PARENT_OFFSET_Y	Y offset in relation to the parent buffer.
M_PARENT_OFFSET_BAND	Band offset in relation to the parent buffer.
M_ANCESTOR_ID	MIL Identifier of the ancestor buffer. (returns same as BufId if no ancestor buffer)
M_ANCESTOR_OFFSET_X	X offset in relation to the ancestor buffer.
M_ANCESTOR_OFFSET_Y	Y offset in relation to the ancestor buffer.
M_ANCESTOR_OFFSET_BAND	Band offset in relation to the ancestor buffer.

(An ancestor buffer is a buffer from which other buffers originated. It must have been allocated with MbufAlloc1d, MbufAlloc2d, or MbufAllocColor and does not have a parent buffer.)

M_MODIFICATION_COUNT

Count of the modifications made to the buffer since its allocation.

(The modification counter is initialized randomly. Call MbufInquire immediately after buffer allocation to determine the starting number.)

M_ASSOCIATED_LUT	Identifier of the LUT buffer associated with the image buffer. (returns M_DEFAULT if no LUT)
M_NATIVE_ID	The native identifier (handle) of the buffer. This identifier can be used when operating in the system native library.
M_WINDOW_DDRAW_SURFACE	Pointer (LPDDRAWSURFACE) to the DirectDraw surface associated with the MIL buffer (if any) or M_NULL.
M_WINDOW_DIB_HEADER	Pointer (LPBITMAPINFO) to the header of the DIB associated with the MIL buffer (if any) or M_NULL.
M_WINDOW_DC	Windows display context handle (HDC) (MbufControl) or M_NULL.

M_FORMAT can access a variety of buffer format information, as follows:

– One of the following is returned by M_FORMAT:

M_MONO1	1 bit per pixel in monochrome format.
M_MONO8	8 bit per pixel in monochrome format.
M_MONO16	16 bit per pixel in monochrome format.
M_MONO32	32 bit per pixel in monochrome format.
M_RGB15	16 bits per pixel in XRGB 1555 format.
M_RGB16	16 bits per pixel in RGB 565 format.
M_RGB24	24 bits per pixel in RGB 888 format.
M_RGB32	32 bits per pixel in XRGB 8888 format.
M_YUV9	YUV9 format.
M_YUV12	YUV12 format.
M_YUV16	YUV16 format.

– Any number of the following might be returned by M_FORMAT:

M_DRAW	The buffer is a DDraw surface.
M_DIB	The buffer is a DIB buffer.
M_FLIP	The buffer is top-down (DIB).
M_ON_BOARD	Memory is allocated on-board.
M_OFF_BOARD	Memory is allocated in Host system memory.
M_PACKED	The buffer bands are packed.
M_PLANAR	The buffer bands are planar.
M_UNSIGNED	The buffer is unsigned.
M_SIGNED	The buffer is signed.
M_FLOAT	The buffer is floating point.

For M_KERNEL and M_STRUCT_ELEMENT data buffers only (see MbufControlNeighborhood for possible values):

M_OVERSCAN	Overscan type.
M_OVERSCAN_REPLACE_VALUE	Overscan replace value.
M_OFFSET_CENTER_X	Offset center X coordinate.
M_OFFSET_CENTER_Y	Offset center Y coordinate.

For M_KERNEL data buffers only (see MbufControlNeighborhood for possible values):

M_ABSOLUTE_VALUE	Absolute value flag.
M_SATURATION	Saturation flag.
M_NORMALIZATION_FACTOR	Normalization factor.

The UserVarPtr parameter specifies the address of the variable in which the requested information is to be written. The variable must be of type long except for M_PARENT_ID, M_OWNER_SYSTEM, and M_ANCESTOR_ID, which require a pointer to a MIL_ID. Since the MbufInquire function also returns the requested information, you can set this parameter to M_NULL.

Returned value

The returned value is the requested MIL buffer parameter setting, cast as long.