1 files changed, 156 insertions, 0 deletions
diff --git a/jni/filters/hsv.c b/jni/filters/hsv.c
new file mode 100644
index 000000000..aabd053fe
--- /dev/null
+++ b/jni/filters/hsv.c
@@ -0,0 +1,156 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * 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 <math.h>
+#include "filters.h"
+
+double fastevalPoly(double *poly,int n, double x){
+
+    double f =x;
+    double sum = poly[0]+poly[1]*f;
+    int i;
+    for (i = 2; i < n; i++) {
+        f*=x;
+        sum += poly[i]*f;
+    }
+    return sum;
+}
+
+void rgb2hsv( unsigned char *rgb,int rgbOff,unsigned short *hsv,int hsvOff)
+{
+    int iMin,iMax,chroma;
+    int ABITS = 4;
+    int HSCALE = 256;
+
+    int k1=255 << ABITS;
+    int k2=HSCALE << ABITS;
+
+    int ri = rgb[rgbOff+0];
+    int gi = rgb[rgbOff+1];
+    int bi = rgb[rgbOff+2];
+    short rv,rs,rh;
+
+    if (ri > gi) {
+        iMax = MAX (ri, bi);
+        iMin = MIN (gi, bi);
+    } else {
+        iMax = MAX (gi, bi);
+        iMin = MIN (ri, bi);
+    }
+
+    chroma = iMax - iMin;
+    // set value
+    rv = (short)( iMax << ABITS);
+
+    // set saturation
+    if (rv == 0)
+        rs = 0;
+    else
+        rs = (short)((k1*chroma)/iMax);
+
+    // set hue
+    if (rs == 0)
+        rh = 0;
+    else {
+        if ( ri == iMax ) {
+            rh  = (short)( (k2*(6*chroma+gi - bi))/(6*chroma));
+            if (rh >= k2) rh -= k2;
+        } else if (gi  == iMax)
+            rh  = (short)( (k2*(2*chroma+bi - ri ))/(6*chroma));
+        else // (bi == iMax )
+                    rh  = (short)( (k2*(4*chroma+ri - gi ))/(6*chroma));
+    }
+    hsv[hsvOff+0] = rv;
+    hsv[hsvOff+1] = rs;
+    hsv[hsvOff+2] = rh;
+}
+
+void hsv2rgb(unsigned short *hsv,int hsvOff, unsigned char *rgb,int rgbOff)
+{
+    int ABITS = 4;
+    int HSCALE = 256;
+    int m;
+    int H,X,ih,is,iv;
+    int k1=255<<ABITS;
+    int k2=HSCALE<<ABITS;
+    int k3=1<<(ABITS-1);
+    int rr=0;
+    int rg=0;
+    int rb=0;
+    short cv = hsv[hsvOff+0];
+    short cs = hsv[hsvOff+1];
+    short ch = hsv[hsvOff+2];
+
+    // set chroma and min component value m
+    //chroma = ( cv * cs )/k1;
+    //m = cv - chroma;
+    m = ((int)cv*(k1 - (int)cs ))/k1;
+
+    // chroma  == 0 <-> cs == 0 --> m=cv
+    if (cs == 0) {
+        rb = ( rg = ( rr =( cv >> ABITS) ));
+    } else {
+        ih=(int)ch;
+        is=(int)cs;
+        iv=(int)cv;
+
+        H = (6*ih)/k2;
+        X = ((iv*is)/k2)*(k2- abs(6*ih- 2*(H>>1)*k2 - k2)) ;
+
+        // removing additional bits --> unit8
+        X=( (X+iv*(k1 - is ))/k1 + k3 ) >> ABITS;
+        m=m >> ABITS;
+
+        // ( chroma + m ) --> cv ;
+        cv=(short) (cv >> ABITS);
+        switch (H) {
+        case 0:
+            rr = cv;
+            rg = X;
+            rb = m;
+            break;
+        case 1:
+            rr = X;
+            rg = cv;
+            rb = m;
+            break;
+        case 2:
+            rr = m;
+            rg = cv;
+            rb = X;
+            break;
+        case 3:
+            rr = m;
+            rg = X;
+            rb = cv;
+            break;
+        case 4:
+            rr = X;
+            rg = m;
+            rb = cv;
+            break;
+        case 5:
+            rr = cv;
+            rg = m ;
+            rb = X;
+            break;
+        }
+    }
+    rgb[rgbOff+0] =  rr;
+    rgb[rgbOff+1] =  rg;
+    rgb[rgbOff+2] =  rb;
+}
+