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      1 /*
      2  * Copyright (C) 2011 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 #define LOG_NDEBUG 0
     17 
     18 #define LOG_TAG "AutoLockTest"
     19 #include <utils/Log.h>
     20 #include <utils/Timers.h>
     21 #include <cmath>
     22 #include <string>
     23 
     24 #include "vec2.h"
     25 #include "vec3.h"
     26 #include "autolocktest.h"
     27 
     28 const float kOverExposure = 230.f;
     29 const float kEqThreshold = 0.05f;
     30 // Processes the color checker values and compare the two values from
     31 // the same individual test.
     32 void AutoLockTest::processData() {
     33     ALOGV("Start Processing Auto Lock Test Data!");
     34 
     35     int numTests = mCheckerColors.size() / 2;
     36     mNumPatches = 0;
     37 
     38     if (numTests > 0) {
     39         mNumPatches = mCheckerColors[0].size();
     40     }
     41 
     42     for (int i = 0; i < numTests; ++i) {
     43         mComparisonResults.push_back(
     44                 IsBrighterThan((&mCheckerColors[i * 2]),
     45                                (&mCheckerColors[i * 2 + 1])));
     46         mComparisonResults.push_back(
     47                 IsEquivalentTo((&mCheckerColors[i * 2]),
     48                                (&mCheckerColors[i * 2 + 1])));
     49     }
     50 }
     51 
     52 // Compares whether one array of gray color patches is brighter than
     53 // another one.
     54 bool AutoLockTest::IsBrighterThan(
     55         const std::vector<Vec3f>* colorCheckers1,
     56         const std::vector<Vec3f>* colorCheckers2) const {
     57     float meanRatio = 0.f;
     58     int meanNumCount = 0;
     59 
     60     for (int i = 0; i < mNumPatches; ++i) {
     61         float luminance1 = (*colorCheckers1)[i].convertToLuminance();
     62         float luminance2 = (*colorCheckers2)[i].convertToLuminance();
     63 
     64         // Consider a 5% raise as a considerably large increase.
     65         if ((luminance1 < kOverExposure) && (luminance2 != 0.f)) {
     66             meanRatio += luminance1 / luminance2;
     67             ++meanNumCount;
     68         }
     69     }
     70     meanRatio = meanRatio / meanNumCount;
     71 
     72     return (meanRatio > 1 + kEqThreshold);
     73 }
     74 
     75 // Compares whether one array of gray color patches is within a small range
     76 // of the other one to be considered equivalent.
     77 bool AutoLockTest::IsEquivalentTo(
     78         const std::vector<Vec3f>* colorCheckers1,
     79         const std::vector<Vec3f>* colorCheckers2) const {
     80     float meanRatio = 0.f;
     81     int meanNumCount = 0;
     82 
     83     for (int i = 0; i < mNumPatches; ++i) {
     84         float luminance1 = (*colorCheckers1)[i].convertToLuminance();
     85         float luminance2 = (*colorCheckers2)[i].convertToLuminance();
     86         ALOGV("Luma_1 and Luma_2 is %f, %f", luminance1, luminance2);
     87 
     88         if ((luminance1 < kOverExposure) && (luminance2 < kOverExposure)) {
     89               meanRatio += luminance2 / luminance1;
     90               ++meanNumCount;
     91         }
     92     }
     93     meanRatio = meanRatio / meanNumCount;
     94 
     95     return ((meanRatio >= 1 - kEqThreshold) && (meanRatio <= 1 + kEqThreshold));
     96 }
     97 
     98 void AutoLockTest::clearData() {
     99     mCheckerColors.clear();
    100     mComparisonResults.clear();
    101 }
    102