Instruction manual

BoardId : board ID returned by el_OpenHW
MemStart : Pointer to array of pointers to picture buffers. NULL pointer terminates array.
SizeX : hor. size of frame buffers
SizeY : vert. size of frame buffers
FrameCount : number of frames allocated
Pitch : hor. pixel offset between subsequent video lines
BuffNo : Pointer to frame buffer identifier
DESCRIPTION: Activates and/or allocates memory buffer for acquisition.
RETURN VALUE:
Pointer to pointer array if OK
.
0 if ERROR. See el_GetErrorCode for details.
Library defined Image Memory Buffers:
If MemStart is NULL el_NewMemBuffer() allocates the necessary memory for the requested picture
(frame) buffers.
The size of the frame buffers allocated and the size of the images acquired is specified with SizeX and
SizeY.
FrameCount specifies the number of buffers in a sequence. If FrameCount is 0, the value for the frame
count is determined by the setup file used with el_InitContext . el_NewMemBuffer allocates as much
frame buffers as specified with FrameCount. The pointers to these frame buffers are stored in an array
allocated by el_NewMemBuffer . A pointer to this array is returned if enough memory for frame buffers is
available. See also: Sequences
It is not allowed to modify the values in this array, because it is used constantly, the buffer is reselected.
Please make a copy of this array (if auto-incrementing pointers are needed) and use the entries of the
copy to access the image. Each pointer of the array points to a contiguous image frame buffer. This
ensures that you can read and write image data from any location in the image just by modifying the
pointers supplied.
Pitch specifies the pixel offset between the start locations of two following lines in an image. If Pitch is set
to 0, the width of the image is used as pitch (on HiPerCam1 Pitch is always equal to SizeX). Every
change of the image width (e.g. by calling el_SetAcqWindow ) will change the pitch too, if the buffer was
created with the Pitch parameter set to 0. Otherwise it is fixed to the specified value.
User defined Image Memory Buffers:
User defined image memory buffers can be used by the library for image acquisition under the following
conditions:
On 64 bit systems user defined memory can only be used with the PCEYE 600/610 grabbers.
If MemStart is not NULL it is expected that MemStart points to an array of valid image buffer pointers. The
supplied pointer array must be NULL terminated. Furthermore it is expected that SizeX and SizeY are not
Chapter 5. Programmers
Reference
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