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 const int u_offset = size;
69 const int v_offset = u_offset + size / 4;
70
71 for (int y = 0; y < height; y += 2) {
72 for (int x = 0; x < width; x += 2) {
73 int u, v, y1, y2, y3, y4;
74
75 y1 = pInY[0];
76 y2 = pInY[1];
77 y3 = pInY[width];
78 y4 = pInY[width + 1];
79
80 u = *pInU - 128;
81 v = *pInV - 128;
82
83 pOutColor[0] = convertYuvToRgba(y1, u, v);
84 pOutColor[1] = convertYuvToRgba(y2, u, v);
85 pOutColor[width] = convertYuvToRgba(y3, u, v);
86 pOutColor[width + 1] = convertYuvToRgba(y4, u, v);
87
88 pInY += 2;
89 pInU++;
90 pInV++;
91 pOutColor += 2;
92 }
93 pInY += width;
94 pOutColor += width;
95 }
96 }
97
JNI_COLORSPACE_METHOD(nativeArgb8888ToRgba8888)98 void JNI_COLORSPACE_METHOD(nativeArgb8888ToRgba8888)(
99 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
100 Rgba* pInput = static_cast<Rgba*>(env->GetDirectBufferAddress(input));
101 Rgba* pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
102
103 for (int i = 0; i < width * height; ++i) {
104 Rgba color_in = *pInput++;
105 Rgba& color_out = *pOutput++;
106 color_out.channel[kRed] = color_in.channel[kGreen];
107 color_out.channel[kGreen] = color_in.channel[kBlue];
108 color_out.channel[kBlue] = color_in.channel[kAlpha];
109 color_out.channel[kAlpha] = color_in.channel[kRed];
110 }
111 }
112
JNI_COLORSPACE_METHOD(nativeRgba8888ToHsva8888)113 void JNI_COLORSPACE_METHOD(nativeRgba8888ToHsva8888)(
114 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
115 Rgba* pInput = static_cast<Rgba*>(env->GetDirectBufferAddress(input));
116 Rgba* pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
117
118 int r, g, b, a, h, s, v, c_max, c_min;
119 float delta;
120 for (int i = 0; i < width * height; ++i) {
121 Rgba color_in = *pInput++;
122 Rgba& color_out = *pOutput++;
123 r = color_in.channel[kRed];
124 g = color_in.channel[kGreen];
125 b = color_in.channel[kBlue];
126 a = color_in.channel[kAlpha];
127
128 if (r > g) {
129 c_min = (g > b) ? b : g;
130 c_max = (r > b) ? r : b;
131 } else {
132 c_min = (r > b) ? b : r;
133 c_max = (g > b) ? g : b;
134 }
135 delta = c_max -c_min;
136
137 float scaler = 255 * 60 / 360.0f;
138 if (c_max == r) {
139 h = (g > b) ? static_cast<int>(scaler * (g - b) / delta) :
140 static_cast<int>(scaler * ((g - b) / delta + 6));
141 } else if (c_max == g) {
142 h = static_cast<int>(scaler * ((b - r) / delta + 2));
143 } else { // Cmax == b
144 h = static_cast<int>(scaler * ((r - g) / delta + 4));
145 }
146 s = (delta == 0.0f) ? 0 : static_cast<unsigned char>(delta / c_max * 255);
147 v = c_max;
148
149 color_out.channel[kRed] = h;
150 color_out.channel[kGreen] = s;
151 color_out.channel[kBlue] = v;
152 color_out.channel[kAlpha] = a;
153 }
154 }
155
JNI_COLORSPACE_METHOD(nativeRgba8888ToYcbcra8888)156 void JNI_COLORSPACE_METHOD(nativeRgba8888ToYcbcra8888)(
157 JNIEnv* env, jclass clazz, jobject input, jobject output, jint width, jint height) {
158 Rgba* pInput = static_cast<Rgba*>(env->GetDirectBufferAddress(input));
159 Rgba* pOutput = static_cast<Rgba*>(env->GetDirectBufferAddress(output));
160
161 int r, g, b;
162 for (int i = 0; i < width * height; ++i) {
163 Rgba color_in = *pInput++;
164 Rgba& color_out = *pOutput++;
165 r = color_in.channel[kRed];
166 g = color_in.channel[kGreen];
167 b = color_in.channel[kBlue];
168
169 color_out.channel[kRed] =
170 static_cast<unsigned char>((65.738 * r + 129.057 * g + 25.064 * b) / 256 + 16);
171 color_out.channel[kGreen] =
172 static_cast<unsigned char>((-37.945 * r - 74.494 * g + 112.439 * b) / 256 + 128);
173 color_out.channel[kBlue] =
174 static_cast<unsigned char>((112.439 * r - 94.154 * g - 18.285 * b) / 256 + 128);
175 color_out.channel[kAlpha] = color_in.channel[kAlpha];
176 }
177 }
178