is_AllocImageMem

USB 2.0

USB 3.0

GigE

USB 2.0

USB 3.0

GigE

Syntax

INT is_AllocImageMem (HIDS hCam,
INT width, INT height, INT bitspixel,
char** ppcImgMem, INT* pid)

Description

is_AllocImageMem() allocates an image memory for an image having its dimensions defined by width and height and its color depth defined by bitspixel. The memory size is at least:

size = [width * ((bitspixel + 1) / 8) + adjust] * height (for details on adjust, see below)

The line increment is calculated as:

line = width * [(bitspixel + 1) / 8]

lineinc = line + adjust

adjust = 0, if line can be divided by 4 without remainder

adjust = 4 - rest(line / 4), if line cannot be divided by 4 without remainder

To read out the line increment, you can use the is_GetImgMemPitch() function.

The starting address of the memory area is returned in ppcImgMem.

pid returns an ID for the allocated memory. A newly allocated memory is not directly active, i.e. digitised images will not be stored immediately in this new memory. It must first be made active using is_SetImageMem().

The returned pointer must be write-protected and may not be altered because it will be used for all further ImageMem functions. To release the memory, you can use is_FreeImageMem().

Hinweis

In the Direct3D modes, image memory allocation is not necessary.

Hinweis

RGB16 and RGB15 require the same amount of memory, but can be distinguished by the bitspixel parameter.

For information on the bit depths of different color formats please refer to the Appendix: Color and memory formats chapter.

Hinweis

In case the operating system is short of physical memory, today's OS versions swap individual areas of the RAM that have not been used for some time out to the slower hard disk. This can slow down image capture if more image memory has been allocated than can be provided by the RAM at a time.

Input parameters

hCam	Camera handle
width	Image width
height	Image height
bitspixel	Image bit depth (bits per pixel).
ppcImgMem	Returns the pointer to the memory starting address
pid	Returns the ID of this memory

Return values

IS_CANT_ADD_TO_SEQUENCE	The image memory is already included in the sequence and cannot be added again.
IS_INVALID_CAMERA_HANDLE	Invalid camera handle
IS_INVALID_MEMORY_POINTER	Invalid pointer or invalid memory ID
IS_INVALID_PARAMETER	One of the submitted parameters is outside the valid range or is not supported for this sensor or is not available in this mode.
IS_NO_SUCCESS	General error message
IS_OUT_OF_MEMORY	No memory could be allocated.
IS_SEQUENCE_BUF_ALREADY_LOCKED	The memory could not be locked. The pointer to the buffer is invalid.
IS_SUCCESS	Function executed successfully

Related functions

•is_FreeImageMem()

•is_AddToSequence()

•is_SetImageMem()

•is_SetAllocatedImageMem()

•is_GetColorDepth()

•is_GetImgMemPitch()

Sample programs

•uEyeRotationDemo (C++)

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is_AllocImageMem