root/trunk/lib/cc3-ilp/cc3_frame_diff.c

/*
 * Copyright 2006  Anthony Rowe and Adam Goode
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */


#include "cc3.h"
#include "cc3_ilp.h"
#include "cc3_frame_diff.h"
#include <stdbool.h>
#include <stdio.h>



uint8_t cc3_frame_diff_scanline_start(cc3_frame_diff_pkt_t *pkt)
{
uint8_t x,y;

if(pkt->previous_template==NULL ) return 0;
if((pkt->load_frame==0) && pkt->current_template==NULL ) return 0;

        // clear frame
        for(y=0; y<pkt->template_height; y++ )
        for(x=0; x<pkt->template_width; x++ )
        {
        if(pkt->load_frame)
                ((uint32_t *)pkt->previous_template)[(y*pkt->template_width)+x]=0;
        else
                ((uint32_t *)pkt->current_template)[(y*pkt->template_width)+x]=0;
        }

pkt->_scratch_y=0;
pkt->_bin_div_x=(pkt->total_x/pkt->template_width);
pkt->_bin_div_y=(pkt->total_y/pkt->template_height);
pkt->x0=UINT16_MAX;
pkt->y0=UINT16_MAX;
pkt->x1=0;
pkt->y1=0;
pkt->centroid_x=0;
pkt->centroid_y=0;
pkt->num_pixels=0;
pkt->int_density=0;
return 1;
}

uint8_t cc3_frame_diff_scanline(cc3_image_t *img, cc3_frame_diff_pkt_t *pkt)
{
uint32_t x,y;
uint16_t t_x,t_y;
cc3_pixel_t cp;


for(y=pkt->_scratch_y; y<(pkt->_scratch_y+img->height); y++ )
{
t_y=y/pkt->_bin_div_y;
for(x=0; x<img->width; x++ )
{
        uint8_t i;
        cc3_get_pixel( img, x, y-pkt->_scratch_y, &cp );
        t_x=x/pkt->_bin_div_x;
        // avoid rounding errors causing a buffer overflow
        if(t_x<pkt->template_width && t_y<pkt->template_height)
        if(pkt->load_frame)
        {
                   ((uint32_t *)pkt->previous_template)[(t_y*pkt->template_width)+t_x]+=cp.channel[0];
        } else {
                   ((uint32_t *)pkt->current_template)[(t_y*pkt->template_width)+t_x]+=cp.channel[0];
        }       
}
}
pkt->_scratch_y=y;

return 1;
}



uint8_t cc3_frame_diff_scanline_finish(cc3_frame_diff_pkt_t *pkt)
{
uint16_t x,y,st,ct;
uint32_t cube_size;
int32_t dif;

        cube_size=pkt->_bin_div_x * pkt->_bin_div_y;
        // divide each square in template by the total number of pixels
        for(y=0; y<pkt->template_height; y++ )
        {
        for(x=0; x<pkt->template_width; x++ )
        {
                if(pkt->load_frame) {
                   ((uint32_t *)pkt->previous_template)[(y*pkt->template_width)+x]=
                   ((uint32_t *)pkt->previous_template)[(y*pkt->template_width)+x]/cube_size;
                } else {
                   ct=((uint32_t *)pkt->current_template)[(y*pkt->template_width)+x]=
                   ((uint32_t *)pkt->current_template)[(y*pkt->template_width)+x]/cube_size;
                   st= ((uint32_t *)pkt->previous_template)[(y*pkt->template_width)+x];
                    // generate the bounding box etc here       
                   dif=ct-st;
                   if(dif<0) dif*=-1;
                   if(dif>pkt->threshold)
                        {
                        if(pkt->x0>x) pkt->x0=x;
                        if(pkt->y0>y) pkt->y0=y;
                        if(pkt->x1<x) pkt->x1=x;
                        if(pkt->y1<y) pkt->y1=y;
                        pkt->centroid_x+=x;
                        pkt->centroid_y+=y;
                        pkt->num_pixels++;
                        }                               
                }
        }
        }
 
   if(!pkt->load_frame)
   {       
        if (pkt->num_pixels > 0) {
        // FIXME:  Density hack to keep it an integer
        pkt->int_density =
                (pkt->num_pixels * 100) / ((pkt->x1 - pkt->x0) * (pkt->y1 - pkt->y0));
        pkt->centroid_x = pkt->centroid_x / pkt->num_pixels;
        pkt->centroid_y = pkt->centroid_y / pkt->num_pixels;

        }
        else {
        pkt->int_density = 0;
        pkt->x0 = 0;
        pkt->y0 = 0;
        pkt->x1 = 0;
        pkt->y1 = 0;
        pkt->centroid_x = 0;
        pkt->centroid_y = 0;

        }
  }

        
return 1;
}