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.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 34import java.lang.Math; 35import java.util.Set; 36 37/** 38 * @hide 39 */ 40public class FisheyeFilter extends Filter { 41 private static final String TAG = "FisheyeFilter"; 42 43 // This parameter has range between 0 and 1. It controls the effect of radial distortion. 44 // The larger the value, the more prominent the distortion effect becomes (a straight line 45 // becomes a curve). 46 @GenerateFieldPort(name = "scale", hasDefault = true) 47 private float mScale = 0f; 48 49 @GenerateFieldPort(name = "tile_size", hasDefault = true) 50 private int mTileSize = 640; 51 52 private Program mProgram; 53 54 private int mWidth = 0; 55 private int mHeight = 0; 56 private int mTarget = FrameFormat.TARGET_UNSPECIFIED; 57 58 private static final String mFisheyeShader = 59 "precision mediump float;\n" + 60 "uniform sampler2D tex_sampler_0;\n" + 61 "uniform vec2 scale;\n" + 62 "uniform float alpha;\n" + 63 "uniform float radius2;\n" + 64 "uniform float factor;\n" + 65 "varying vec2 v_texcoord;\n" + 66 "void main() {\n" + 67 " const float m_pi_2 = 1.570963;\n" + 68 " vec2 coord = v_texcoord - vec2(0.5, 0.5);\n" + 69 " float dist = length(coord * scale);\n" + 70 " float radian = m_pi_2 - atan(alpha * sqrt(radius2 - dist * dist), dist);\n" + 71 " float scalar = radian * factor / dist;\n" + 72 " vec2 new_coord = coord * scalar + vec2(0.5, 0.5);\n" + 73 " gl_FragColor = texture2D(tex_sampler_0, new_coord);\n" + 74 "}\n"; 75 76 public FisheyeFilter(String name) { 77 super(name); 78 } 79 80 @Override 81 public void setupPorts() { 82 addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA)); 83 addOutputBasedOnInput("image", "image"); 84 } 85 86 @Override 87 public FrameFormat getOutputFormat(String portName, FrameFormat inputFormat) { 88 return inputFormat; 89 } 90 91 public void initProgram(FilterContext context, int target) { 92 switch (target) { 93 case FrameFormat.TARGET_GPU: 94 ShaderProgram shaderProgram = new ShaderProgram(context, mFisheyeShader); 95 shaderProgram.setMaximumTileSize(mTileSize); 96 mProgram = shaderProgram; 97 break; 98 99 default: 100 throw new RuntimeException("Filter FisheyeFilter does not support frames of " + 101 "target " + target + "!"); 102 } 103 mTarget = target; 104 } 105 106 @Override 107 public void process(FilterContext context) { 108 // Get input frame 109 Frame input = pullInput("image"); 110 FrameFormat inputFormat = input.getFormat(); 111 112 // Create output frame 113 Frame output = context.getFrameManager().newFrame(inputFormat); 114 115 // Create program if not created already 116 if (mProgram == null || inputFormat.getTarget() != mTarget) { 117 initProgram(context, inputFormat.getTarget()); 118 } 119 120 // Check if the frame size has changed 121 if (inputFormat.getWidth() != mWidth || inputFormat.getHeight() != mHeight) { 122 updateFrameSize(inputFormat.getWidth(), inputFormat.getHeight()); 123 } 124 125 // Process 126 mProgram.process(input, output); 127 128 // Push output 129 pushOutput("image", output); 130 131 // Release pushed frame 132 output.release(); 133 } 134 135 @Override 136 public void fieldPortValueUpdated(String name, FilterContext context) { 137 if (mProgram != null) { 138 updateProgramParams(); 139 } 140 } 141 142 private void updateFrameSize(int width, int height) { 143 mWidth = width; 144 mHeight = height; 145 146 updateProgramParams(); 147 } 148 149 private void updateProgramParams() { 150 final float pi = 3.14159265f; 151 float scale[] = new float[2]; 152 if (mWidth > mHeight) { 153 scale[0] = 1f; 154 scale[1] = ((float) mHeight) / mWidth; 155 } else { 156 scale[0] = ((float) mWidth) / mHeight; 157 scale[1] = 1f; 158 } 159 float alpha = mScale * 2.0f + 0.75f; 160 float bound2 = 0.25f * (scale[0] * scale[0] + scale[1] * scale[1]); 161 float bound = (float) Math.sqrt(bound2); 162 float radius = 1.15f * bound; 163 float radius2 = radius * radius; 164 float max_radian = 0.5f * pi - 165 (float) Math.atan(alpha / bound * (float) Math.sqrt(radius2 - bound2)); 166 float factor = bound / max_radian; 167 168 mProgram.setHostValue("scale", scale); 169 mProgram.setHostValue("radius2",radius2); 170 mProgram.setHostValue("factor", factor); 171 mProgram.setHostValue("alpha", alpha); 172 } 173} 174