GetSequenceWindow (DVR version only)

Description

Returns the two-dimensional array of pixel values corresponding to the selected window in the frame of the memory sequence.


Syntax

[VB]
Value=objActiveGige.GetImageWindow (Frame, X, Y, Width, Height)

[C/C++]
HRESULT GetImageWindow( long iFrame, short X, short Y, short Width, short Height, VARIANT* pArray );


Data Types [VB]

X,Y, Width, Height: Integer
Return value: Variant (SAFEARRAY)


Parameters [C/C++]

iFrame [in]

The zero-based index of the frame in the memory sequence

X [in], Y[in]

The x- and y-coordinates of the top left pixel of the window in the entire frame

Width [in], Height [in]

The horizontal and vertical size of the window in pixels.

pArray [out,retval]

Pointer to the SAFEARRAY containing the pixel values in the frame

Return Values

S_OK

Success

E_FAIL

Failure.

Example

This VB example fills a 3D array (x, y, frame) with pixel values from the memory sequence.


For z= 0 To ActiveGige1.GetSequenceFrameCount-1
sx=ActiveGige1.SizeX
sy=ActiveGige1.SizeY
a = ActiveGige1.GetSequenceWindow (z, 0, 0, sx, sy)
For x = 0 To sx-1
For y = 0 To sy-1
M(x,y,z) = a(x, y)
Next
Next
Next

Remarks

The image data in the array are stored in the standard order from top to bottom, therefore the first element of the array is the top left pixel of the window. The type of data and dimensions of the array returned by GetSequenceWindow depends on the output format of the video, the width and height of the window and the number of lines acquired, as specified in the following table:

Camera Pixel Format	Output Format	Data type	Dimensions
Mono8	8-bit monochrome	Byte	0 to SizeX -1, 0 to Lines - 1
Mono10, Mono12, Mono16	16-bit gray monochrome	Integer (word)	0 to SizeX -1, 0 to Lines - 1
YUV411, YUV422, YUV444, RGB8, BGR8, Bayer8	24-bit RGB	Byte	0 to SizeX * 3 - 1, 0 to Lines - 1
RGB10, RGB12, RGB16, BGR10, BGR12, Bayer 10, Bayer 12, Bayer16	48-bit RGB	Integer (word)	0 to SizeX * 3 - 1, 0 to Lines - 1

If the dimensions of the window are too large to accommodate the frame size, they will be clipped to the frame boundaries.

For integer (word) type of data you can receive negative numbers if pixel values exceed 32767. In C and C# you can convert signed integers to unsigned ones by using data casting. To get rid of negative values in VB and Delphi, subtract them from 65535.

Note that in C/C++ applications it is required to call SafeArrayDestroy() to delete the SAFEARRAY returned by GetSequenceWindow.