1 /*
2 * Copyright (C) 2013 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 "colorspace.h"
18
19 #include <jni.h>
20 #include <stdint.h>
21
22 typedef uint8_t uint8;
23 typedef uint32_t uint32;
24 typedef int32_t int32;
25
26 // RGBA helper struct allows access as int and individual channels
27 // WARNING: int value depends on endianness and should not be used to analyze individual channels.
28 union Rgba {
29 uint32 color;
30 uint8 channel[4];
31 };
32
33 // Channel index constants
34 static const uint8 kRed = 0;
35 static const uint8 kGreen = 1;
36 static const uint8 kBlue = 2;
37 static const uint8 kAlpha = 3;
38
39 // Clamp to range 0-255
clamp(int32 x)40 static inline uint32 clamp(int32 x) {
41 return x > 255 ? 255 : (x < 0 ? 0 : x);
42 }
43
44 // Convert YUV to RGBA
45 // This uses the ITU-R BT.601 coefficients.
convertYuvToRgba(int32 y,int32 u,int32 v)46 static inline Rgba convertYuvToRgba(int32 y, int32 u, int32 v) {
47 Rgba color;
48 color.channel[kRed] = clamp(y + static_cast<int>(1.402 * v));
49 color.channel[kGreen] = clamp(y - static_cast<int>(0.344 * u + 0.714 * v));
50 color.channel[kBlue] = clamp(y + static_cast<int>(1.772 * u));
51 color.channel[kAlpha] = 0xFF;
52 return color;
53 }
54
55 // Colorspace conversion functions /////////////////////////////////////////////////////////////////
JNI_COLORSPACE_METHOD(nativeYuv420pToRgba8888)56 void JNI_COLORSPACE_METHOD(nativeYuv420pToRgba8888)(
57 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
58 uint8* const pInput = static_cast<uint8*>(env->GetDirectBufferAddress(input));
59 Rgba* const pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
60
61 const int size = width * height;
62
63 uint8* pInY = pInput;
64 uint8* pInU = pInput + size;
65 uint8* pInV = pInput + size + size / 4;
66 Rgba* pOutColor = pOutput;
67
68 for (int y = 0; y < height; y += 2) {
69 for (int x = 0; x < width; x += 2) {
70 int u, v, y1, y2, y3, y4;
71
72 y1 = pInY[0];
73 y2 = pInY[1];
74 y3 = pInY[width];
75 y4 = pInY[width + 1];
76
77 u = *pInU - 128;
78 v = *pInV - 128;
79
80 pOutColor[0] = convertYuvToRgba(y1, u, v);
81 pOutColor[1] = convertYuvToRgba(y2, u, v);
82 pOutColor[width] = convertYuvToRgba(y3, u, v);
83 pOutColor[width + 1] = convertYuvToRgba(y4, u, v);
84
85 pInY += 2;
86 pInU++;
87 pInV++;
88 pOutColor += 2;
89 }
90 pInY += width;
91 pOutColor += width;
92 }
93 }
94
JNI_COLORSPACE_METHOD(nativeArgb8888ToRgba8888)95 void JNI_COLORSPACE_METHOD(nativeArgb8888ToRgba8888)(
96 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
97 Rgba* pInput = static_cast<Rgba*>(env->GetDirectBufferAddress(input));
98 Rgba* pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
99
100 for (int i = 0; i < width * height; ++i) {
101 Rgba color_in = *pInput++;
102 Rgba& color_out = *pOutput++;
103 color_out.channel[kRed] = color_in.channel[kGreen];
104 color_out.channel[kGreen] = color_in.channel[kBlue];
105 color_out.channel[kBlue] = color_in.channel[kAlpha];
106 color_out.channel[kAlpha] = color_in.channel[kRed];
107 }
108 }
109
JNI_COLORSPACE_METHOD(nativeRgba8888ToHsva8888)110 void JNI_COLORSPACE_METHOD(nativeRgba8888ToHsva8888)(
111 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
112 Rgba* pInput = static_cast<Rgba*>(env->GetDirectBufferAddress(input));
113 Rgba* pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
114
115 int r, g, b, a, h, s, v, c_max, c_min;
116 float delta;
117 for (int i = 0; i < width * height; ++i) {
118 Rgba color_in = *pInput++;
119 Rgba& color_out = *pOutput++;
120 r = color_in.channel[kRed];
121 g = color_in.channel[kGreen];
122 b = color_in.channel[kBlue];
123 a = color_in.channel[kAlpha];
124
125 if (r > g) {
126 c_min = (g > b) ? b : g;
127 c_max = (r > b) ? r : b;
128 } else {
129 c_min = (r > b) ? b : r;
130 c_max = (g > b) ? g : b;
131 }
132 delta = c_max -c_min;
133
134 float scaler = 255 * 60 / 360.0f;
135 if (c_max == r) {
136 h = (g > b) ? static_cast<int>(scaler * (g - b) / delta) :
137 static_cast<int>(scaler * ((g - b) / delta + 6));
138 } else if (c_max == g) {
139 h = static_cast<int>(scaler * ((b - r) / delta + 2));
140 } else { // Cmax == b
141 h = static_cast<int>(scaler * ((r - g) / delta + 4));
142 }
143 s = (delta == 0.0f) ? 0 : static_cast<unsigned char>(delta / c_max * 255);
144 v = c_max;
145
146 color_out.channel[kRed] = h;
147 color_out.channel[kGreen] = s;
148 color_out.channel[kBlue] = v;
149 color_out.channel[kAlpha] = a;
150 }
151 }
152
JNI_COLORSPACE_METHOD(nativeRgba8888ToYcbcra8888)153 void JNI_COLORSPACE_METHOD(nativeRgba8888ToYcbcra8888)(
154 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
155 Rgba* pInput = static_cast<Rgba*>(env->GetDirectBufferAddress(input));
156 Rgba* pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
157
158 int r, g, b;
159 for (int i = 0; i < width * height; ++i) {
160 Rgba color_in = *pInput++;
161 Rgba& color_out = *pOutput++;
162 r = color_in.channel[kRed];
163 g = color_in.channel[kGreen];
164 b = color_in.channel[kBlue];
165
166 color_out.channel[kRed] =
167 static_cast<unsigned char>((65.738 * r + 129.057 * g + 25.064 * b) / 256 + 16);
168 color_out.channel[kGreen] =
169 static_cast<unsigned char>((-37.945 * r - 74.494 * g + 112.439 * b) / 256 + 128);
170 color_out.channel[kBlue] =
171 static_cast<unsigned char>((112.439 * r - 94.154 * g - 18.285 * b) / 256 + 128);
172 color_out.channel[kAlpha] = color_in.channel[kAlpha];
173 }
174 }
175