1/*
2 * Copyright (C) 2010 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// YUVCanvas holds a reference to a YUVImage on which it can do various
18// drawing operations. It provides various utility functions for filling,
19// cropping, etc.
20
21
22#ifndef YUV_CANVAS_H_
23
24#define YUV_CANVAS_H_
25
26#include <stdint.h>
27
28namespace android {
29
30class YUVImage;
31class Rect;
32
33class YUVCanvas {
34public:
35
36    // Constructor takes in reference to a yuvImage on which it can do
37    // various drawing opreations.
38    YUVCanvas(YUVImage &yuvImage);
39    ~YUVCanvas();
40
41    // Fills the entire image with the given YUV values.
42    void FillYUV(uint8_t yValue, uint8_t uValue, uint8_t vValue);
43
44    // Fills the rectangular region [startX,endX]x[startY,endY] with the given YUV values.
45    void FillYUVRectangle(const Rect& rect,
46            uint8_t yValue, uint8_t uValue, uint8_t vValue);
47
48    // Copies the region [startX,endX]x[startY,endY] from srcImage into the
49    // canvas' target image (mYUVImage) starting at
50    // (destinationStartX,destinationStartY).
51    // Note that undefined behavior may occur if srcImage is same as the canvas'
52    // target image.
53    void CopyImageRect(
54            const Rect& srcRect,
55            int32_t destStartX, int32_t destStartY,
56            const YUVImage &srcImage);
57
58    // Downsamples the srcImage into the canvas' target image (mYUVImage)
59    // The downsampling copies pixels from the source image starting at
60    // (srcOffsetX, srcOffsetY) to the target image, starting at (0, 0).
61    // For each X increment in the target image, skipX pixels are skipped
62    // in the source image.
63    // Similarly for each Y increment in the target image, skipY pixels
64    // are skipped in the source image.
65    void downsample(
66            int32_t srcOffsetX, int32_t srcOffsetY,
67            int32_t skipX, int32_t skipY,
68            const YUVImage &srcImage);
69
70private:
71    YUVImage& mYUVImage;
72
73    YUVCanvas(const YUVCanvas &);
74    YUVCanvas &operator=(const YUVCanvas &);
75};
76
77}  // namespace android
78
79#endif  // YUV_CANVAS_H_
80