// http://www.cs.rit.edu/~ncs/color/t_convert.html
void rgb_to_hsv(image im)
{
assert(im.c == 3);
int i, j;
float r, g, b;
float h, s, v;
for(j = 0; j < im.h; ++j){
for(i = 0; i < im.w; ++i){
r = get_pixel(im, i , j, 0);
g = get_pixel(im, i , j, 1);
b = get_pixel(im, i , j, 2);
float max = three_way_max(r,g,b);
float min = three_way_min(r,g,b);
float delta = max - min;
v = max;
if(max == 0){
s = 0;
h = -1;
}else{
s = delta/max;
if(r == max){
h = (g - b) / delta;
} else if (g == max) {
h = 2 + (b - r) / delta;
} else {
h = 4 + (r - g) / delta;
}
if (h < 0) h += 6;
}
set_pixel(im, i, j, 0, h);
set_pixel(im, i, j, 1, s);
set_pixel(im, i, j, 2, v);
}
}
}
int
strncmp_ea (__ea void *s1, __ea const void *s2, size_ea_t n3)
{
__ea void *curr_s1 = (__ea void *) s1;
__ea void *curr_s2 = (__ea void *) s2;
void *l_s1;
void *l_s2;
int min;
size_ea_t s2_n;
size_ea_t s1_n;
int ret;
vec_uint4 end_v;
ret = 0; /* in case n3 is 0 */
while (n3)
{
l_s2 = __cache_fetch (curr_s2);
l_s1 = __cache_fetch (curr_s1);
/*
* Use the smaller of the size left to compare (n3), the space left in
* s2 cacheline (s2_n), or the space left in the s1 cacheline (s1_n)
*/
s2_n = ROUND_UP_NEXT_128 ((size_ea_t) curr_s2) - (size_ea_t) curr_s2;
s1_n = ROUND_UP_NEXT_128 ((size_ea_t) curr_s1) - (size_ea_t) curr_s1;
min = three_way_min (s2_n, s1_n, n3);
ret = _strncmp_internal (l_s1, l_s2, min, &end_v, 1);
/*
* Only the first slot of end_v is set.
*/
/* if (ret || spu_extract(spu_cmpeq(end_v, 0), 0)) { */
/* if (ret || spu_extract(spu_gather(spu_cmpeq(end_v, 0)), 0)) { */
if (ret || spu_extract (end_v, 0))
/*
* If any NUL values were seen (end_v values of zero) we still have
* to return ret, as it might not be zero.
*/
return ret;
curr_s2 += min;
curr_s1 += min;
n3 -= min;
}
return ret;
}