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Init sRGB2HSV

This commit is contained in:
JonDeen 2015-06-09 12:23:30 +02:00
parent de80d7758d
commit a47f3c0321
1 changed files with 33 additions and 3 deletions
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36
libvips/colour/sRGB2HSV.c
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@ -54,10 +54,40 @@ vips_sRGB2HSV_line( VipsColour *colour, VipsPel *out, VipsPel **in, int width )
unsigned char *q = (unsigned char *) out;
int i;
float c1,c2,c3,c_max,c_min,delta,x;
for( i = 0; i < width; i++ ) {
q[0] = p[0];
q[1] = p[1];
q[2] = p[2];
c1=(float)p[0]/(float)255.0;
c2=(float)p[1]/(float)255.0;
c3=(float)p[2]/(float)255.0;
c_max=VIPS_MAX(c1,VIPS_MAX(c2,c3));
c_min=VIPS_MIN(c1,VIPS_MIN(c2,c3));
delta=c_max-c_min;
float normalization = 256.0/(float)6.0;
if (delta == 0.0) {
q[0] = 0;
} else if (c_max == c1) {
x = ((c2 - c3) / delta);
if (c2 < c3) x += 6.0;
q[0] = (int) x * normalization;
} else if (c_max == c2) {
q[0] = (int) (((c3 - c1) / delta) + 2) * normalization;
} else if (c_max == c3) {
q[0] = (int) (((c1 - c2) / delta) + 4) * normalization;
}
if (c_max == 0.0) {
q[1]=0;
} else {
q[1]= (int) 256.0*delta/c_max;
}
q[2]=c_max;
p += 3;
q += 3;