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
17package android.filterpacks.imageproc;
18
19import android.filterfw.core.Filter;
20import android.filterfw.core.FilterContext;
21import android.filterfw.core.Frame;
22import android.filterfw.core.FrameFormat;
23import android.filterfw.core.GenerateFieldPort;
24import android.filterfw.core.MutableFrameFormat;
25import android.filterfw.core.Program;
26import android.filterfw.core.ShaderProgram;
27import android.filterfw.format.ImageFormat;
28
29public class ImageSlicer extends Filter {
30
31    @GenerateFieldPort(name = "xSlices")
32    private int mXSlices;
33
34    @GenerateFieldPort(name = "ySlices")
35    private int mYSlices;
36
37    @GenerateFieldPort(name = "padSize")
38    private int mPadSize;
39
40    // The current slice index from 0 to xSlices * ySlices
41    private int mSliceIndex;
42
43    private Frame mOriginalFrame;
44
45    private Program mProgram;
46
47    private int mInputWidth;
48    private int mInputHeight;
49
50    private int mSliceWidth;
51    private int mSliceHeight;
52
53    private int mOutputWidth;
54    private int mOutputHeight;
55
56    public ImageSlicer(String name) {
57        super(name);
58        mSliceIndex = 0;
59    }
60
61    @Override
62    public void setupPorts() {
63        addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA,
64                                                       FrameFormat.TARGET_GPU));
65        addOutputBasedOnInput("image", "image");
66    }
67
68    @Override
69    public FrameFormat getOutputFormat(String portName, FrameFormat inputFormat) {
70        return inputFormat;
71    }
72
73    private void calcOutputFormatForInput(Frame frame) {
74
75        // calculate the output size based on input size, xSlices, and ySlices
76        mInputWidth = frame.getFormat().getWidth();
77        mInputHeight = frame.getFormat().getHeight();
78
79        mSliceWidth = (mInputWidth + mXSlices - 1) / mXSlices;
80        mSliceHeight = (mInputHeight + mYSlices - 1)/ mYSlices;
81
82        mOutputWidth = mSliceWidth + mPadSize * 2;
83        mOutputHeight = mSliceHeight + mPadSize * 2;
84    }
85
86
87    @Override
88    public void process(FilterContext context) {
89
90        // Get input frame
91        if (mSliceIndex == 0) {
92            mOriginalFrame = pullInput("image");
93            calcOutputFormatForInput(mOriginalFrame);
94        }
95
96        FrameFormat inputFormat = mOriginalFrame.getFormat();
97        MutableFrameFormat outputFormat = inputFormat.mutableCopy();
98        outputFormat.setDimensions(mOutputWidth, mOutputHeight);
99
100        // Create output frame
101        Frame output = context.getFrameManager().newFrame(outputFormat);
102
103        // Create the program if not created already
104        if (mProgram == null) {
105            mProgram = ShaderProgram.createIdentity(context);
106        }
107
108        // Calculate the four corner of the source region
109        int xSliceIndex = mSliceIndex % mXSlices;
110        int ySliceIndex = mSliceIndex / mXSlices;
111
112        // TODO(rslin) : not sure shifting by 0.5 is needed.
113        float x0 = (xSliceIndex * mSliceWidth - mPadSize) / ((float) mInputWidth);
114        float y0 = (ySliceIndex * mSliceHeight - mPadSize) / ((float) mInputHeight);
115
116        ((ShaderProgram) mProgram).setSourceRect(x0, y0,
117                                                 ((float) mOutputWidth) / mInputWidth,
118                                                 ((float) mOutputHeight) / mInputHeight);
119
120        // Process
121        mProgram.process(mOriginalFrame, output);
122        mSliceIndex++;
123
124        if (mSliceIndex == mXSlices * mYSlices) {
125            mSliceIndex = 0;
126            mOriginalFrame.release();
127            setWaitsOnInputPort("image", true);
128        } else {
129            // Retain the original frame so it can be used next time.
130            mOriginalFrame.retain();
131            setWaitsOnInputPort("image", false);
132        }
133
134        // Push output
135        pushOutput("image", output);
136
137        // Release pushed frame
138        output.release();
139    }
140}
141