create_dimage ( : Image : Type, Width, Height, PixelPointer, ClearProc : )

Create an image from a pointer on the pixels with storage management.

The operator create_dimagecreates an image of the size Width * Height. The pixels in PixelPointer are stored line-sequentially. The type of the given pixels (PixelPointer) must correspond to (Type). Since the type of the parameter PixelPointer is generic (long) a cast must be used for the call.

The memory for the new image is not newly allocated by HORUS contrary to create_image, and thus is not copied either. This means that the memory space that PixelPointer points to must be released when deleting the object Image. This is done by the procedure ClearProc provided by the caller. This procedure must have the following signature:

void ClearProc(void* ptr);

It is called when deleting Image. If the memory shall not be released (in the case of frame grabbers or static memory) a procedure "without trunk" or the NULL-Pointer can be passed. Analogous to the parameter PixelPointer the pointer has to be passed to the procedure by casting it to long.


Parameters

Image (output_object)
image -> object
Created HORUS image.

Type (input_control)
string -> string
Pixel type
Default value: 'byte'
List of values: 'int1', 'int2', 'int4', 'byte', 'real', 'direction', 'cyclic'

Width (input_control)
extent.x -> integer
Width of image
Default value: 512
Suggested values: 128, 256, 512, 1024
Range of values: 1 <= Width <= 512 (lin)
Minimum increment: 1
Recommended increment: 10
Restriction: Width >= 1

Height (input_control)
extent.y -> integer
Height of image
Default value: 512
Suggested values: 128, 256, 512, 1024
Range of values: 1 <= Height <= 512 (lin)
Minimum increment: 1
Recommended increment: 10
Restriction: Height >= 1

PixelPointer (input_control)
integer -> integer
Pointer to the first gray value

ClearProc (input_control)
integer -> integer
Pointer to the procedure re-releasing the memory of the image when deleting the object.
Default value: 0


Example
void NewImage(ObjType *new)
{
  unsigned char  *image;
  int            r,c;
  image = malloc(768*525);
  for (r=0; r<525; r++)
    for (c=0; c<768; c++)
      image[r*768+c] = c % 255;
  create_dimage(new,"byte",768,525,(long)image,(long)free);
}

Result

The operator create_dimage returns the value TRUE if the parameter values are correct. Otherwise an exception is raised.


Alternatives

create_image, new_image__, get_image_pointer__


See also

reduce_domain, paint_grey__, paint_region__, set_greyval__



Copyright © 1996-1997 MVTec Software GmbH