1 /*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "filters.h"
18
estmateWhite(unsigned char * src,int len,int * wr,int * wb,int * wg)19 void estmateWhite(unsigned char *src, int len, int *wr, int *wb, int *wg){
20
21 int STEP = 4;
22 int RANGE = 256;
23 int *histR = (int *) malloc(256*sizeof(int));
24 int *histG = (int *) malloc(256*sizeof(int));
25 int *histB = (int *) malloc(256*sizeof(int));
26 int i;
27 for (i = 0; i < 255; i++) {
28 histR[i] = histG[i] = histB[i] =0;
29 }
30
31 for (i = 0; i < len; i+=STEP) {
32 histR[(src[RED])]++;
33 histG[(src[GREEN])]++;
34 histB[(src[BLUE])]++;
35 }
36 int min_r = -1, min_g = -1,min_b = -1;
37 int max_r = 0, max_g = 0,max_b = 0;
38 int sum_r = 0,sum_g=0,sum_b=0;
39
40 for (i = 1; i < RANGE-1; i++) {
41 int r = histR[i];
42 int g = histG[i];
43 int b = histB[i];
44 sum_r += r;
45 sum_g += g;
46 sum_b += b;
47
48 if (r>0){
49 if (min_r < 0) min_r = i;
50 max_r = i;
51 }
52 if (g>0){
53 if (min_g < 0) min_g = i;
54 max_g = i;
55 }
56 if (b>0){
57 if (min_b < 0) min_b = i;
58 max_b = i;
59 }
60 }
61
62 int sum15r = 0,sum15g=0,sum15b=0;
63 int count15r = 0,count15g=0,count15b=0;
64 int tmp_r = 0,tmp_g=0,tmp_b=0;
65
66 for (i = RANGE-2; i >0; i--) {
67 int r = histR[i];
68 int g = histG[i];
69 int b = histB[i];
70 tmp_r += r;
71 tmp_g += g;
72 tmp_b += b;
73
74 if ((tmp_r > sum_r/20) && (tmp_r < sum_r/5)) {
75 sum15r += r*i;
76 count15r += r;
77 }
78 if ((tmp_g > sum_g/20) && (tmp_g < sum_g/5)) {
79 sum15g += g*i;
80 count15g += g;
81 }
82 if ((tmp_b > sum_b/20) && (tmp_b < sum_b/5)) {
83 sum15b += b*i;
84 count15b += b;
85 }
86
87 }
88 free(histR);
89 free(histG);
90 free(histB);
91
92 if ((count15r>0) && (count15g>0) && (count15b>0) ){
93 *wr = sum15r/count15r;
94 *wb = sum15g/count15g;
95 *wg = sum15b/count15b;
96 }else {
97 *wg = *wb = *wr=255;
98 }
99 }
100
estmateWhiteBox(unsigned char * src,int iw,int ih,int x,int y,int * wr,int * wb,int * wg)101 void estmateWhiteBox(unsigned char *src, int iw, int ih, int x,int y, int *wr, int *wb, int *wg){
102 int r = 0;
103 int g = 0;
104 int b = 0;
105 int sum = 0;
106 int xp,yp;
107 int bounds = 5;
108 if (x<0) x = bounds;
109 if (y<0) y = bounds;
110 if (x>=(iw-bounds)) x = (iw-bounds-1);
111 if (y>=(ih-bounds)) y = (ih-bounds-1);
112 int startx = x - bounds;
113 int starty = y - bounds;
114 int endx = x + bounds;
115 int endy = y + bounds;
116
117 for(yp= starty;yp<endy;yp++) {
118 for(xp= startx;xp<endx;xp++) {
119 int i = 4*(xp+yp*iw);
120 r += src[RED];
121 g += src[GREEN];
122 b += src[BLUE];
123 sum++;
124 }
125 }
126 *wr = r/sum;
127 *wg = g/sum;
128 *wb = b/sum;
129 }
130
JNIFUNCF(ImageFilterWBalance,nativeApplyFilter,jobject bitmap,jint width,jint height,int locX,int locY)131 void JNIFUNCF(ImageFilterWBalance, nativeApplyFilter, jobject bitmap, jint width, jint height, int locX,int locY)
132 {
133 char* destination = 0;
134 AndroidBitmap_lockPixels(env, bitmap, (void**) &destination);
135 int i;
136 int len = width * height * 4;
137 unsigned char * rgb = (unsigned char * )destination;
138 int wr;
139 int wg;
140 int wb;
141
142 if (locX==-1)
143 estmateWhite(rgb,len,&wr,&wg,&wb);
144 else
145 estmateWhiteBox(rgb, width, height,locX,locY,&wr,&wg,&wb);
146
147 int min = MIN(wr, MIN(wg, wb));
148 int max = MAX(wr, MAX(wg, wb));
149 float avg = (min+max)/2.f;
150 float scaleR = avg/wr;
151 float scaleG = avg/wg;
152 float scaleB = avg/wb;
153
154 for (i = 0; i < len; i+=4)
155 {
156 int r = rgb[RED];
157 int g = rgb[GREEN];
158 int b = rgb[BLUE];
159
160 float Rc = r*scaleR;
161 float Gc = g*scaleG;
162 float Bc = b*scaleB;
163
164 rgb[RED] = clamp(Rc);
165 rgb[GREEN] = clamp(Gc);
166 rgb[BLUE] = clamp(Bc);
167 }
168 AndroidBitmap_unlockPixels(env, bitmap);
169 }
170