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
18package android.filterpacks.imageproc;
19
20import android.filterfw.core.Filter;
21import android.filterfw.core.FilterContext;
22import android.filterfw.core.Frame;
23import android.filterfw.core.FrameFormat;
24import android.filterfw.core.GenerateFieldPort;
25import android.filterfw.core.Program;
26import android.filterfw.core.ShaderProgram;
27import android.filterfw.format.ImageFormat;
28import android.filterfw.geometry.Quad;
29import android.filterfw.geometry.Point;
30
31/**
32 * @hide
33 */
34public class StraightenFilter extends Filter {
35
36    @GenerateFieldPort(name = "angle", hasDefault = true)
37    private float mAngle = 0f;
38
39    @GenerateFieldPort(name = "maxAngle", hasDefault = true)
40    private float mMaxAngle = 45f;
41
42    @GenerateFieldPort(name = "tile_size", hasDefault = true)
43    private int mTileSize = 640;
44
45    private Program mProgram;
46
47    private int mWidth = 0;
48    private int mHeight = 0;
49    private int mTarget = FrameFormat.TARGET_UNSPECIFIED;
50
51    private static final float DEGREE_TO_RADIAN = (float) Math.PI / 180.0f;
52
53    public StraightenFilter(String name) {
54        super(name);
55    }
56
57    @Override
58    public void setupPorts() {
59        addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA));
60        addOutputBasedOnInput("image", "image");
61    }
62
63    public void initProgram(FilterContext context, int target) {
64        switch (target) {
65            case FrameFormat.TARGET_GPU:
66                ShaderProgram shaderProgram = ShaderProgram.createIdentity(context);
67                shaderProgram.setMaximumTileSize(mTileSize);
68                mProgram = shaderProgram;
69                break;
70
71            default:
72                throw new RuntimeException("Filter Sharpen does not support frames of " +
73                    "target " + target + "!");
74        }
75        mTarget = target;
76    }
77
78    @Override
79    public void fieldPortValueUpdated(String name, FilterContext context) {
80        if (mProgram != null) {
81            updateParameters();
82        }
83    }
84
85    @Override
86    public void process(FilterContext context) {
87        // Get input frame
88        Frame input = pullInput("image");
89        FrameFormat inputFormat = input.getFormat();
90
91        // Create program if not created already
92        if (mProgram == null || inputFormat.getTarget() != mTarget) {
93            initProgram(context, inputFormat.getTarget());
94        }
95
96        // Create output frame
97        if (inputFormat.getWidth() != mWidth || inputFormat.getHeight() != mHeight) {
98            mWidth = inputFormat.getWidth();
99            mHeight = inputFormat.getHeight();
100            updateParameters();
101        }
102
103        Frame output = context.getFrameManager().newFrame(inputFormat);
104
105        // Process
106        mProgram.process(input, output);
107
108        // Push output
109        pushOutput("image", output);
110
111        // Release pushed frame
112        output.release();
113    }
114
115    private void updateParameters() {
116        float cosTheta = (float) Math.cos(mAngle * DEGREE_TO_RADIAN);
117        float sinTheta = (float) Math.sin(mAngle * DEGREE_TO_RADIAN);
118
119        if (mMaxAngle <= 0)
120            throw new RuntimeException("Max angle is out of range (0-180).");
121        mMaxAngle = (mMaxAngle > 90) ? 90 : mMaxAngle;
122
123        Point p0 = new Point(-cosTheta * mWidth + sinTheta * mHeight,
124                             -sinTheta * mWidth - cosTheta * mHeight);
125
126        Point p1 = new Point(cosTheta * mWidth + sinTheta * mHeight,
127                             sinTheta * mWidth - cosTheta * mHeight);
128
129        Point p2 = new Point(-cosTheta * mWidth - sinTheta * mHeight,
130                             -sinTheta * mWidth + cosTheta * mHeight);
131
132        Point p3 = new Point(cosTheta * mWidth - sinTheta * mHeight,
133                             sinTheta * mWidth + cosTheta * mHeight);
134
135        float maxWidth = (float) Math.max(Math.abs(p0.x), Math.abs(p1.x));
136        float maxHeight = (float) Math.max(Math.abs(p0.y), Math.abs(p1.y));
137
138        float scale = 0.5f * Math.min( mWidth / maxWidth,
139                                       mHeight / maxHeight);
140
141        p0.set(scale * p0.x / mWidth + 0.5f, scale * p0.y / mHeight + 0.5f);
142        p1.set(scale * p1.x / mWidth + 0.5f, scale * p1.y / mHeight + 0.5f);
143        p2.set(scale * p2.x / mWidth + 0.5f, scale * p2.y / mHeight + 0.5f);
144        p3.set(scale * p3.x / mWidth + 0.5f, scale * p3.y / mHeight + 0.5f);
145
146        Quad quad = new Quad(p0, p1, p2, p3);
147        ((ShaderProgram) mProgram).setSourceRegion(quad);
148    }
149}
150