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 
17 /*
18  * Contains implemenation of framebuffer conversion routines.
19  */
20 
21 #define LOG_NDEBUG 0
22 #define LOG_TAG "EmulatedCamera_Converter"
23 #include <cutils/log.h>
24 #include "Converters.h"
25 
26 #include "Alignment.h"
27 
28 namespace android {
29 
_YUV420SToRGB565(const uint8_t * Y,const uint8_t * U,const uint8_t * V,int dUV,uint16_t * rgb,int width,int height,int y_stride,int uv_stride)30 static void _YUV420SToRGB565(const uint8_t* Y,
31                              const uint8_t* U,
32                              const uint8_t* V,
33                              int dUV,
34                              uint16_t* rgb,
35                              int width,
36                              int height,
37                              int y_stride,
38                              int uv_stride)
39 {
40     const uint8_t* Y_pos = Y;
41     const uint8_t* U_pos = U;
42     const uint8_t* V_pos = V;
43 
44     for (int y = 0; y < height; y++) {
45         Y = Y_pos + y_stride * y;
46         U = U_pos + uv_stride * (y / 2);
47         V = V_pos + uv_stride * (y / 2);
48         for (int x = 0; x < width; x += 2, U += dUV, V += dUV) {
49             const uint8_t nU = *U;
50             const uint8_t nV = *V;
51             *rgb = YUVToRGB565(*Y, nU, nV);
52             Y++; rgb++;
53             *rgb = YUVToRGB565(*Y, nU, nV);
54             Y++; rgb++;
55         }
56     }
57 }
58 
_YUV420SToRGB32(const uint8_t * Y,const uint8_t * U,const uint8_t * V,int dUV,uint32_t * rgb,int width,int height,int y_stride,int uv_stride)59 static void _YUV420SToRGB32(const uint8_t* Y,
60                             const uint8_t* U,
61                             const uint8_t* V,
62                             int dUV,
63                             uint32_t* rgb,
64                             int width,
65                             int height,
66                             int y_stride,
67                             int uv_stride)
68 {
69     const uint8_t* Y_pos = Y;
70     const uint8_t* U_pos = U;
71     const uint8_t* V_pos = V;
72 
73     for (int y = 0; y < height; y++) {
74         Y = Y_pos + y_stride * y;
75         U = U_pos + uv_stride * (y / 2);
76         V = V_pos + uv_stride * (y / 2);
77         for (int x = 0; x < width; x += 2, U += dUV, V += dUV) {
78             const uint8_t nU = *U;
79             const uint8_t nV = *V;
80             *rgb = YUVToRGB32(*Y, nU, nV);
81             Y++; rgb++;
82             *rgb = YUVToRGB32(*Y, nU, nV);
83             Y++; rgb++;
84         }
85     }
86 }
87 
88 /* The YV12 and YU12 formats require that the row strides are aligned to 16 byte
89  * boundaries as per the format specification at:
90  * https://developer.android.com/reference/android/graphics/ImageFormat.html#YV12
91  *
92  * This means that we can't just use the width or assume that pixels are
93  * tightly packed, we have to calculate aligned strides and use them to find the
94  * next row.
95  */
YV12ToRGB565(const void * yv12,void * rgb,int width,int height)96 void YV12ToRGB565(const void* yv12, void* rgb, int width, int height)
97 {
98     // See note above about alignment
99     const int y_stride = align(width, 16);
100     const int uv_stride = align(y_stride / 2, 16);
101     const uint8_t* Y = reinterpret_cast<const uint8_t*>(yv12);
102     const uint8_t* U = Y + y_stride * height;
103     const uint8_t* V = U + uv_stride * (height / 2);
104     _YUV420SToRGB565(Y, U, V, 1, reinterpret_cast<uint16_t*>(rgb),
105                      width, height, y_stride, uv_stride);
106 }
107 
YV12ToRGB32(const void * yv12,void * rgb,int width,int height)108 void YV12ToRGB32(const void* yv12, void* rgb, int width, int height)
109 {
110     // See note above about alignment
111     const int y_stride = align(width, 16);
112     const int uv_stride = align(y_stride / 2, 16);
113     const uint8_t* Y = reinterpret_cast<const uint8_t*>(yv12);
114     const uint8_t* V = Y + y_stride * height;
115     const uint8_t* U = V + uv_stride * (height / 2);
116     _YUV420SToRGB32(Y, U, V, 1, reinterpret_cast<uint32_t*>(rgb), width, height,
117                     y_stride, uv_stride);
118 }
119 
YU12ToRGB32(const void * yu12,void * rgb,int width,int height)120 void YU12ToRGB32(const void* yu12, void* rgb, int width, int height)
121 {
122     // See note above about alignment
123     const int y_stride = align(width, 16);
124     const int uv_stride = align(y_stride / 2, 16);
125     const uint8_t* Y = reinterpret_cast<const uint8_t*>(yu12);
126     const uint8_t* U = Y + y_stride * height;
127     const uint8_t* V = U + uv_stride * (height / 2);
128     _YUV420SToRGB32(Y, U, V, 1, reinterpret_cast<uint32_t*>(rgb), width, height,
129                     y_stride, uv_stride);
130 }
131 
132 /* Common converter for YUV 4:2:0 interleaved to RGB565.
133  * y, u, and v point to Y,U, and V panes, where U and V values are interleaved.
134  */
_NVXXToRGB565(const uint8_t * Y,const uint8_t * U,const uint8_t * V,uint16_t * rgb,int width,int height)135 static void _NVXXToRGB565(const uint8_t* Y,
136                           const uint8_t* U,
137                           const uint8_t* V,
138                           uint16_t* rgb,
139                           int width,
140                           int height)
141 {
142     // The UV stride for NV21 and NV12 is the same as the width because the
143     // U and V values are interleaved, making each row twice as wide even though
144     // each value covers a two pixel wide area. These formats do not require any
145     // kind of alignment.
146     int y_stride = width;
147     int uv_stride = width;
148     _YUV420SToRGB565(Y, U, V, 2, rgb, width, height, y_stride, uv_stride);
149 }
150 
151 /* Common converter for YUV 4:2:0 interleaved to RGB32.
152  * y, u, and v point to Y,U, and V panes, where U and V values are interleaved.
153  */
_NVXXToRGB32(const uint8_t * Y,const uint8_t * U,const uint8_t * V,uint32_t * rgb,int width,int height)154 static void _NVXXToRGB32(const uint8_t* Y,
155                          const uint8_t* U,
156                          const uint8_t* V,
157                          uint32_t* rgb,
158                          int width,
159                          int height)
160 {
161     // The UV stride for NV21 and NV12 is the same as the width because the
162     // U and V values are interleaved, making each row twice as wide even though
163     // each value covers a two pixel wide area. These formats do not require any
164     // kind of alignment.
165     int y_stride = width;
166     int uv_stride = width;
167     _YUV420SToRGB32(Y, U, V, 2, rgb, width, height, y_stride, uv_stride);
168 }
169 
NV12ToRGB565(const void * nv12,void * rgb,int width,int height)170 void NV12ToRGB565(const void* nv12, void* rgb, int width, int height)
171 {
172     const int pix_total = width * height;
173     const uint8_t* y = reinterpret_cast<const uint8_t*>(nv12);
174     _NVXXToRGB565(y, y + pix_total, y + pix_total + 1,
175                   reinterpret_cast<uint16_t*>(rgb), width, height);
176 }
177 
NV12ToRGB32(const void * nv12,void * rgb,int width,int height)178 void NV12ToRGB32(const void* nv12, void* rgb, int width, int height)
179 {
180     const int pix_total = width * height;
181     const uint8_t* y = reinterpret_cast<const uint8_t*>(nv12);
182     _NVXXToRGB32(y, y + pix_total, y + pix_total + 1,
183                  reinterpret_cast<uint32_t*>(rgb), width, height);
184 }
185 
NV21ToRGB565(const void * nv21,void * rgb,int width,int height)186 void NV21ToRGB565(const void* nv21, void* rgb, int width, int height)
187 {
188     const int pix_total = width * height;
189     const uint8_t* y = reinterpret_cast<const uint8_t*>(nv21);
190     _NVXXToRGB565(y, y + pix_total + 1, y + pix_total,
191                   reinterpret_cast<uint16_t*>(rgb), width, height);
192 }
193 
NV21ToRGB32(const void * nv21,void * rgb,int width,int height)194 void NV21ToRGB32(const void* nv21, void* rgb, int width, int height)
195 {
196     const int pix_total = width * height;
197     const uint8_t* y = reinterpret_cast<const uint8_t*>(nv21);
198     _NVXXToRGB32(y, y + pix_total + 1, y + pix_total,
199                  reinterpret_cast<uint32_t*>(rgb), width, height);
200 }
201 
202 }; /* namespace android */
203