Project Name: median.dpj

Project Type:
    ADSP-BF533 [X]
    ADSP-BF537 [ ]
    ADSP-BF561 [ ]

Hardware Used:
    ADSP-BF533 EZ-Kit
    VisualDSP++ Emulator

System Services Components Used:
    None


OVERVIEW
========
In the median function, each pixel is replaced by median of gray
levels in a neighbourhood of that pixel. Border of the output
image is same as input image. The median M of a set of values is
such that half the values in the set are less than M and half are
greater than M. This filter removes the effect of extreme values
from data. This routine is helpful in removing the effect of
impulsive noise in images.

The algorithm is implemented as follows: The 3x3 median filtering
is used here. The 3 elements of each row are arranged in MAX,MED
and  MIN values.

             | MAX0  MED0  MIN0 |
             | MAX1  MED1  MIN1 |
             | MAX2  MED2  MIN2 |

Later, the MIN of the first column, the median of the second column
and the MAX of the third column are taken.  The median of the three
pixels is written as output.  In the output image, the border pixels
are the same as the input pixel.

Prototype:
 void _median(unsigned char* in, int row, int col, unsigned char *out );

Arguments:
    in   ->  pointer to the input image.
    row  ->  number of rows of input image.
    col  ->  number of columns of input image.
    out  ->  pointer the output buffer.

Registers used  : R0-R7, I0, M0, P0-P5, LC0, LC1.




RUNNING THE APPLICATION (on the ADSP-BF533 EZ-KIT Lite)
=========================================================

1) Load project "median.dpj".

2) Select "Project->Rebuild Project"

3) Select "Debug->Run".

4) Observe output on VisualDSP++ console window.



Files in This Application
==========================

This example consists of the following files:

    "./median.ldf" - linker description file
    "./median.dpj" - project file
    "../../src/t_median.c" -  source file
    "../../src/median.asm" -  source file
    "../../include/median.h" -  include file
    "../../../../BFinUtils/ADSP-BF533/SDK-cycle_count.asm" -  source file
    "../../../../Include/SDK-cycle_count.asm" -  source file