| .TH IM_OFFSETS45 3 "28 May 1991" |
| .SH NAME |
| im_offsets45, im_offsets90, im_rotate_imask45, im_rotate_dmask45, |
| im_rotate_imask90, im_rotate_dmask90 \- rotate square masks |
| .SH SYNOPSIS |
| |
| .B int *im_offsets45( size ) |
| .br |
| .B int size; |
| |
| .B int *im_offsets90( size ) |
| .br |
| .B int size; |
| |
| .B INTMASK *im_rotate_imask45( m, name ) |
| .br |
| .B INTMASK *m; |
| .br |
| .B char *name; |
| |
| .B DOUBLEMASK *im_rotate_dmask45( m, name ) |
| .br |
| .B DOUBLEMASK *m; |
| .br |
| .B char *name; |
| |
| .B INTMASK *im_rotate_imask90( m, name ) |
| .br |
| .B INTMASK *m; |
| .br |
| .B char *name; |
| |
| .B DOUBLEMASK *im_rotate_dmask90( m, name ) |
| .br |
| .B DOUBLEMASK *m; |
| .br |
| .B char *name; |
| |
| .SH DESCRIPTION |
| These functions can be used to produce the integer offsets needed to rotate |
| masks by 45 or 90 degrees clockwise. |
| |
| .B im_offsets45() |
| accepts only even size and returns a pointer to an int buffer of size*size. |
| The program mallocs the buffer and puts into it the integer offsets needed to |
| rotate a mask of even size size by 45 degrees. For instance if size is 3 the |
| program returns the buffer 3 0 1 6 4 2 7 8 5 which is the offsets needed to |
| rotate a mask with offsets 0 1 2 3 4 5 6 7 8. The function return a |
| pointer to valid data on success or NULL on error. Since the program mallocs |
| a buffer, the user should free the returned pointer accordingly. |
| |
| .B im_offsets90() |
| accepts any size and returns a pointer to an int buffer of size*size. The |
| program mallocs the buffer and puts into it the integer offsets needed to |
| rotate a mask of size size by 90 degrees. For instance if size is 3 the |
| program returns the buffer 6 3 0 7 4 1 8 5 2 which is the offsets needed to |
| rotate a mask with offsets 0 1 2 3 4 5 6 7 8. The function return a |
| pointers to valid data on success or NULL on error. Since the program mallocs |
| a buffer, the user should free the returned pointer accordingly. |
| |
| .B im_rotate_imask45() |
| rotates the INTMASK m by 45 degrees and returns the rotated mask. The filename |
| member of the returned structure is set to name. The program allocates memory |
| for the new mask and therefore the user must free the returned mask by a call |
| to im_free_imask(3). The returned mask is rotated by 45 degrees clockwise. |
| The function return a valid INTMASK pointer on success or NULL on error. |
| |
| .B im_rotate_dmask45() |
| rotates the DOUBLEMASK m by 45 degrees |
| and returns the rotated mask. The filename |
| member of the returned structure is set to name. The program allocates memory |
| for the new mask and therefore the user must free the returned mask by a call |
| to im_free_dmask(3). The returned mask is rotated by 45 degrees clockwise. |
| The function return a valid DOUBLEMASK pointer on success or NULL on error. |
| |
| .B im_rotate_imask90() |
| rotates the INTMASK m by 90 degrees and returns the rotated mask. The filename |
| member of the returned structure is set to name. The program allocates memory |
| for the new mask and therefore the user must free the returned mask by a call |
| to im_free_imask(3). The returned mask is rotated by 90 degrees clockwise. |
| The function return a valid INTMASK pointer on success or NULL on error. |
| |
| .B im_rotate_dmask90() |
| rotates the DOUBLEMASK m by 90 degrees |
| and returns the rotated mask. The filename |
| member of the returned structure is set to name. The program allocates memory |
| for the new mask and therefore the user must free the returned mask by a call |
| to im_free_dmask(3). The returned mask is rotated by 90 degrees clockwise. |
| The function return a valid DOUBLEMASK pointer on success or NULL on error. |
| |
| .SH RETURN VALUE |
| .SH SEE ALSO |
| im_read_imask(3), im_read_dmask(3), im_free_imask(3), im_free_dmask(3), |
| im_gradient(3), im_compass(3), im_conv(3). |
| .SH COPYRIGHT |
| .br |
| N. Dessipris |
| .SH AUTHOR |
| N. Dessipris \-28/05/1991 |
