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 <math.h> 18 #include "filters.h" 19 20 void JNIFUNCF(ImageFilterBwFilter, nativeApplyFilter, jobject bitmap, jint width, jint height, jint rw, jint gw, jint bw) 21 { 22 char* destination = 0; 23 AndroidBitmap_lockPixels(env, bitmap, (void**) &destination); 24 unsigned char * rgb = (unsigned char * )destination; 25 float sr = rw; 26 float sg = gw; 27 float sb = bw; 28 29 float min = MIN(sg,sb); 30 min = MIN(sr,min); 31 float max = MAX(sg,sb); 32 max = MAX(sr,max); 33 float avg = (min+max)/2; 34 sb /= avg; 35 sg /= avg; 36 sr /= avg; 37 int i; 38 int len = width * height * 4; 39 40 for (i = 0; i < len; i+=4) 41 { 42 float r = sr *rgb[RED]; 43 float g = sg *rgb[GREEN]; 44 float b = sb *rgb[BLUE]; 45 min = MIN(g,b); 46 min = MIN(r,min); 47 max = MAX(g,b); 48 max = MAX(r,max); 49 avg =(min+max)/2; 50 rgb[RED] = CLAMP(avg); 51 rgb[GREEN] = rgb[RED]; 52 rgb[BLUE] = rgb[RED]; 53 } 54 AndroidBitmap_unlockPixels(env, bitmap); 55 } 56