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 "MeteringTest"
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 "meteringtest.h"
27
28 const float kOverExposure = 230.f;
29 const float kEqThreshold = 0.05f;
30 // Processes the checker colors stored by comparing the pixel values from the
31 // two scenarios in a test.
processData()32 void MeteringTest::processData() {
33 ALOGV("Start Processing Metering 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 isEquivalentTo((&mCheckerColors[i * 2]),
45 (&mCheckerColors[i * 2 + 1])));
46 mComparisonResults.push_back(
47 isDarkerThan((&mCheckerColors[i * 2]),
48 (&mCheckerColors[i * 2 + 1])));
49 }
50 }
51
clearData()52 void MeteringTest::clearData() {
53 mComparisonResults.clear();
54 mCheckerColors.clear();
55 }
56
57 // Compares two given arrays of pixel values and decide whether the first one is
58 // significantly darker than the second one.
isDarkerThan(const std::vector<Vec3f> * checkerColors1,const std::vector<Vec3f> * checkerColors2) const59 bool MeteringTest::isDarkerThan(
60 const std::vector<Vec3f>* checkerColors1,
61 const std::vector<Vec3f>* checkerColors2) const {
62 float meanRatio = 0.f;
63 int meanNumCount = 0;
64
65 for (int i = 0; i < mNumPatches; ++i) {
66 float luminance1 = (*checkerColors1)[i].convertToLuminance();
67 float luminance2 = (*checkerColors2)[i].convertToLuminance();
68
69 // Out of the saturation rage, define 5% as a margin for being
70 // significantly brighter.
71 if ((luminance2 < kOverExposure) && (luminance1 != 0.f)) {
72 meanRatio += luminance2 / luminance1;
73 ++meanNumCount;
74 }
75 }
76 meanRatio = meanRatio / meanNumCount;
77
78 return (meanRatio > 1 + kEqThreshold);
79 }
80
81 // Compares the two givn arrays of pixel values and decide whether they are
82 // equivalent within an acceptable range.
isEquivalentTo(const std::vector<Vec3f> * checkerColors1,const std::vector<Vec3f> * checkerColors2) const83 bool MeteringTest::isEquivalentTo(
84 const std::vector<Vec3f>* checkerColors1,
85 const std::vector<Vec3f>* checkerColors2) const {
86 float meanRatio = 0.f;
87 int meanNumCount = 0;
88
89 for (int i = 0; i < mNumPatches; ++i) {
90 float luminance1 = (*checkerColors1)[i].convertToLuminance();
91 float luminance2 = (*checkerColors2)[i].convertToLuminance();
92 ALOGV("Luma_1 and Luma_2 is %f, %f", luminance1, luminance2);
93
94 if ((luminance1 < kOverExposure) && (luminance2 < kOverExposure)) {
95 meanRatio += luminance2 / luminance1;
96 ++meanNumCount;
97 }
98 }
99 meanRatio = meanRatio / meanNumCount;
100
101 return ((meanRatio >= 1 - kEqThreshold) && (meanRatio <= 1 + kEqThreshold));
102 }
103