img_boundary.h64

dm642函数库

;* ======================================================================== *;
;*  TEXAS INSTRUMENTS, INC.                                                 *;
;*                                                                          *;
;*  IMGLIB  DSP Image/Video Processing Library                              *;
;*                                                                          *;
;*      Release:        Revision 1.04b                                      *;
;*      CVS Revision:   1.4     Sun Sep 29 03:32:18 2002 (UTC)              *;
;*      Snapshot date:  23-Oct-2003                                         *;
;*                                                                          *;
;*  This library contains proprietary intellectual property of Texas        *;
;*  Instruments, Inc.  The library and its source code are protected by     *;
;*  various copyrights, and portions may also be protected by patents or    *;
;*  other legal protections.                                                *;
;*                                                                          *;
;*  This software is licensed for use with Texas Instruments TMS320         *;
;*  family DSPs.  This license was provided to you prior to installing      *;
;*  the software.  You may review this license by consulting the file       *;
;*  TI_license.PDF which accompanies the files in this library.             *;
;* ------------------------------------------------------------------------ *;
;*          Copyright (C) 2003 Texas Instruments, Incorporated.             *;
;*                          All Rights Reserved.                            *;
;* ======================================================================== *;
;* ======================================================================== *;
;*  Assembler compatibility shim for assembling 4.30 and later code on      *;
;*  tools prior to 4.30.                                                    *;
;* ======================================================================== *;
;* ======================================================================== *;
;*  End of assembler compatibility shim.                                    *;
;* ======================================================================== *;
* ========================================================================= *
*                                                                           *
*   NAME                                                                    *
*       IMG_boundary -- Returns coordinates of IMG_boundary pixels.         *
*                                                                           *
*   REVISION DATE                                                           *
*       10-Jul-2001                                                         *
*                                                                           *
*   USAGE                                                                   *
*       This routine is C callable, and is called as follows:               *
*                                                                           *
*           void IMG_boundary                                               *
*           (                                                               *
*               const unsigned char *restrict i_data,                       *
*               int rows, int cols,                                         *
*               int *restrict o_coord,                                      *
*               int *restrict o_grey                                        *
*           );                                                              *
*                                                                           *
*       The arguments are defined as follows:                               *
*                                                                           *
*           i_data   Input images that is cols-by-rows in size.             *
*           rows     Height of the input image                              *
*           cols     Width of the input image                               *
*           o_coord  Array to write output coordinates to                   *
*           o_grey   Array to write output grey levels to                   *
*                                                                           *
*   DESCRIPTION                                                             *
*       This routine scans an image looking for non-zero pixels.            *
*       The locations of those pixels are stored out to the o_coord         *
*       as packed Y/X pairs, with Y in the upper half, and X in             *
*       the lower half.  The grey levels encountered are stored             *
*       in the o_grey array in parallel.                                    *
*                                                                           *
*       The following is a C code description of the kernel without         *
*       restrictions.  This implementation has restrictions as noted        *
*       in the assumptions below.                                           *
*                                                                           *
*         void IMG_boundary                                                 *
*         (                                                                 *
*             const unsigned char *restrict i_data,                         *
*             int rows, int cols,                                           *
*             int *restrict o_coord,                                        *
*             int *restrict o_grey                                          *
*         )                                                                 *
*         {                                                                 *
*             int x, y, p;                                                  *
*                                                                           *
*             for (y = 0; y < rows; y++)                                    *
*                 for (x = 0; x < cols; x++)                                *
*                     if ((p = i_data[x + y*cols] != 0)                     *
*                     {                                                     *
*                         *o_coord++ = ((y & 0xFFFF) << 16) |               *
*                                       (x & 0xFFFF);                       *
*                         *o_grey++  = p;                                   *
*                     }                                                     *
*         }                                                                 *
*                                                                           *
*   ASSUMPTIONS                                                             *
*       At least one row is being processed.                                *
*                                                                           *
*       Input is word aligned.                                              *
*                                                                           *
*       Input is a multiple of 4 pixels wide.                               *
*                                                                           *
*       Output buffers o_coord and o_grey start in different banks          *
*       and are word-aligned.                                               *
*                                                                           *
*       No more than 32764 rows or 32764 columns are being processed.       *
*                                                                           *
*   TECHNIQUES                                                              *
*       Outer and inner loops are collapsed together.                       *
*       Inner loop is unrolled to process four pixels per iteration.        *
*       Packed coordinate value is updated directly, rather than            *
*       by repacking x, y every time it's needed.                           *
*                                                                           *
*   MEMORY NOTE                                                             *
*       No bank conflicts occur as long as o_coord and o_grey start         *
*       in different banks.  If they start in the same bank, every          *
*       access to each array will cause a bank conflict.                    *
*                                                                           *
*   NOTES                                                                   *
*       This code blocks interrupts for nearly its entire duration.         *
*       It is interrupt tolerant, but not interruptible.                    *
*                                                                           *
*   CYCLES                                                                  *
*       cycles = (5 * rows * cols) / 4 + 12.                                *
*                                                                           *
*   CODESIZE                                                                *
*       132 bytes                                                           *
* ------------------------------------------------------------------------- *
*             Copyright (c) 2003 Texas Instruments, Incorporated.           *
*                            All Rights Reserved.                           *
* ========================================================================= *

        .global _IMG_boundary

* ========================================================================= *
*   End of file:  img_boundary.h64                                          *
* ------------------------------------------------------------------------- *
*             Copyright (c) 2003 Texas Instruments, Incorporated.           *
*                            All Rights Reserved.                           *
* ========================================================================= *