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.KeyValueMap;
26import android.filterfw.core.MutableFrameFormat;
27import android.filterfw.core.NativeProgram;
28import android.filterfw.core.NativeFrame;
29import android.filterfw.core.Program;
30import android.filterfw.core.ShaderProgram;
31import android.filterfw.format.ImageFormat;
32
33import android.util.Log;
34
35import java.lang.reflect.Field;
36
37/**
38 * @hide
39 */
40public class ToGrayFilter extends SimpleImageFilter {
41
42    @GenerateFieldPort(name = "invertSource", hasDefault = true)
43    private boolean mInvertSource = false;
44
45    @GenerateFieldPort(name = "tile_size", hasDefault = true)
46    private int mTileSize = 640;
47
48    private MutableFrameFormat mOutputFormat;
49
50    private static final String mColorToGray4Shader =
51            "precision mediump float;\n" +
52            "uniform sampler2D tex_sampler_0;\n" +
53            "varying vec2 v_texcoord;\n" +
54            "void main() {\n" +
55            "  vec4 color = texture2D(tex_sampler_0, v_texcoord);\n" +
56            "  float y = dot(color, vec4(0.299, 0.587, 0.114, 0));\n" +
57            "  gl_FragColor = vec4(y, y, y, color.a);\n" +
58            "}\n";
59
60    public ToGrayFilter(String name) {
61        super(name, null);
62    }
63
64    @Override
65    public void setupPorts() {
66        addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA,
67                                                       FrameFormat.TARGET_GPU));
68        addOutputBasedOnInput("image", "image");
69    }
70
71    @Override
72    protected Program getNativeProgram(FilterContext context) {
73        throw new RuntimeException("Native toGray not implemented yet!");
74    }
75
76    @Override
77    protected Program getShaderProgram(FilterContext context) {
78        int inputChannels = getInputFormat("image").getBytesPerSample();
79        if (inputChannels != 4) {
80            throw new RuntimeException("Unsupported GL input channels: " +
81                                       inputChannels + "! Channels must be 4!");
82        }
83        ShaderProgram program = new ShaderProgram(context, mColorToGray4Shader);
84        program.setMaximumTileSize(mTileSize);
85        if (mInvertSource)
86            program.setSourceRect(0.0f, 1.0f, 1.0f, -1.0f);
87        return program;
88    }
89
90}
91