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.GenerateFinalPort;
25import android.filterfw.core.KeyValueMap;
26import android.filterfw.core.NativeProgram;
27import android.filterfw.core.NativeFrame;
28import android.filterfw.core.Program;
29import android.filterfw.core.ShaderProgram;
30import android.filterfw.format.ImageFormat;
31
32import android.util.Log;
33
34public class FillLightFilter extends Filter {
35
36    @GenerateFieldPort(name = "tile_size", hasDefault = true)
37    private int mTileSize = 640;
38
39    @GenerateFieldPort(name = "strength", hasDefault = true)
40    private float mBacklight = 0f;
41
42    private Program mProgram;
43
44    private int mTarget = FrameFormat.TARGET_UNSPECIFIED;
45
46    private final String mFillLightShader =
47            "precision mediump float;\n" +
48            "uniform sampler2D tex_sampler_0;\n" +
49            "uniform float mult;\n" +
50            "uniform float igamma;\n" +
51            "varying vec2 v_texcoord;\n" +
52            "void main()\n" +
53            "{\n" +
54            "  const vec3 color_weights = vec3(0.25, 0.5, 0.25);\n" +
55            "  vec4 color = texture2D(tex_sampler_0, v_texcoord);\n" +
56            "  float lightmask = dot(color.rgb, color_weights);\n" +
57            "  float backmask = (1.0 - lightmask);\n" +
58            "  vec3 ones = vec3(1.0, 1.0, 1.0);\n" +
59            "  vec3 diff = pow(mult * color.rgb, igamma * ones) - color.rgb;\n" +
60            "  diff = min(diff, 1.0);\n" +
61            "  vec3 new_color = min(color.rgb + diff * backmask, 1.0);\n" +
62            "  gl_FragColor = vec4(new_color, color.a);\n" +
63            "}\n";
64
65    public FillLightFilter(String name) {
66      super(name);
67    }
68
69    @Override
70    public void setupPorts() {
71        addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA));
72        addOutputBasedOnInput("image", "image");
73    }
74
75    @Override
76    public FrameFormat getOutputFormat(String portName, FrameFormat inputFormat) {
77        return inputFormat;
78    }
79
80    public void initProgram(FilterContext context, int target) {
81        switch (target) {
82            case FrameFormat.TARGET_GPU:
83                ShaderProgram shaderProgram = new ShaderProgram(context, mFillLightShader);
84                Log.e("FillLight", "tile size: " + mTileSize);
85                shaderProgram.setMaximumTileSize(mTileSize);
86                mProgram = shaderProgram;
87                break;
88
89            default:
90                throw new RuntimeException("Filter FillLight does not support frames of " +
91                    "target " + target + "!");
92        }
93        mTarget = target;
94    }
95
96
97    @Override
98    public void process(FilterContext context) {
99        // Get input frame
100        Frame input = pullInput("image");
101        FrameFormat inputFormat = input.getFormat();
102
103        // Create output frame
104        Frame output = context.getFrameManager().newFrame(inputFormat);
105
106        // Create program if not created already
107        if (mProgram == null || inputFormat.getTarget() != mTarget) {
108            initProgram(context, inputFormat.getTarget());
109            updateParameters();
110        }
111
112        // Process
113        mProgram.process(input, output);
114
115        // Push output
116        pushOutput("image", output);
117
118        // Release pushed frame
119        output.release();
120    }
121
122
123    @Override
124    public void fieldPortValueUpdated(String name, FilterContext context) {
125        if (mProgram != null) {
126            updateParameters();
127        }
128    }
129
130    private void updateParameters() {
131        float fade_gamma = 0.3f;
132        float amt = 1.0f - mBacklight;
133        float mult = 1.0f / (amt * 0.7f + 0.3f);
134        float faded = fade_gamma + (1.0f -fade_gamma) *mult;
135        float igamma = 1.0f / faded;
136
137        mProgram.setHostValue("mult", mult);
138        mProgram.setHostValue("igamma", igamma);
139    }
140}
141