Alacron FAST-UXGA, Technical Product Manual, Page: 19 / 28

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memclass_t memclass;
int ncomp;
struct image_struct *next;
int id;
} image_t;
Most of these fields are clear. 'nr' number of rows (lines) in the image, sometimes also called
the height of the image. 'nc' is the number of columns, pixels,width of the image. 'st' is the
image stride, or the number of bytes from the left most pixel in a line to the left most pixel in the
next line. Note: It can be negative. 'data' points to the actual image data. The size of this data
area is at least nr*st bytes. 'pfree' points to a function which can free the image data and the
structure. This function is used by the OIL API ImageFree. 'extension' is a pointer to data that
some how extends the image (like a color map). 'memclass' describes the type of memory that
the image data uses. Normally this is local memory. 'ncomp' reflects the number of additional
image structures linked on the 'next' field. For planer images each plane is a separate image
linked in a list on the 'next' field. 'id' is an application specific value.
The OCX only uses nr,nc.st.itype,bpp,data, and ncomp. The other fields are not read.
What is passed to the OCX APIs as a long pointer is a pointer to the image structure in
memory.
The two enum types are:
typedef enum {IMAGE_CLASS_LOCAL=1, IMAGE_CLASS_PCI} memclass_t;
This type indicates the kind of memory being used, which for the host will always be
IMAGE_CLASS_LOCAL. The OCX does not use this field.
typedef enum {
IMAGE_TYPE_GRAY8 = 1,
IMAGE_TYPE_GRAY16,
IMAGE_TYPE_GRAY32,
IMAGE_TYPE_YUV422,
IMAGE_TYPE_YUV420,
IMAGE_TYPE_RGBPLANER,
IMAGE_TYPE_RGB15,
IMAGE_TYPE_RGB16,
IMAGE_TYPE_RGB24,
IMAGE_TYPE_RGB32,
IMAGE_TYPE_GRAY32F,
IMAGE_TYPE_BINARY,
IMAGE_TYPE_RGBPLANER16,
IMAGE_TYPE_RGBPLANER32,
IMAGE_TYPE_RGB48,
IMAGE_TYPE_BINARYR,
IMAGE_TYPE_RGB8_332,