| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| |
| package android.filterpacks.imageproc; |
| |
| import android.filterfw.core.Filter; |
| import android.filterfw.core.FilterContext; |
| import android.filterfw.core.Frame; |
| import android.filterfw.core.FrameFormat; |
| import android.filterfw.core.GenerateFieldPort; |
| import android.filterfw.core.Program; |
| import android.filterfw.core.ShaderProgram; |
| import android.filterfw.format.ImageFormat; |
| |
| import java.lang.Math; |
| |
| /** |
| * @hide |
| */ |
| public class FisheyeFilter extends Filter { |
| private static final String TAG = "FisheyeFilter"; |
| |
| // This parameter has range between 0 and 1. It controls the effect of radial distortion. |
| // The larger the value, the more prominent the distortion effect becomes (a straight line |
| // becomes a curve). |
| @GenerateFieldPort(name = "scale", hasDefault = true) |
| private float mScale = 0f; |
| |
| @GenerateFieldPort(name = "tile_size", hasDefault = true) |
| private int mTileSize = 640; |
| |
| private Program mProgram; |
| |
| private int mWidth = 0; |
| private int mHeight = 0; |
| private int mTarget = FrameFormat.TARGET_UNSPECIFIED; |
| |
| private static final String mFisheyeShader = |
| "precision mediump float;\n" + |
| "uniform sampler2D tex_sampler_0;\n" + |
| "uniform vec2 scale;\n" + |
| "uniform float alpha;\n" + |
| "uniform float radius2;\n" + |
| "uniform float factor;\n" + |
| "varying vec2 v_texcoord;\n" + |
| "void main() {\n" + |
| " const float m_pi_2 = 1.570963;\n" + |
| " vec2 coord = v_texcoord - vec2(0.5, 0.5);\n" + |
| " float dist = length(coord * scale);\n" + |
| " float radian = m_pi_2 - atan(alpha * sqrt(radius2 - dist * dist), dist);\n" + |
| " float scalar = radian * factor / dist;\n" + |
| " vec2 new_coord = coord * scalar + vec2(0.5, 0.5);\n" + |
| " gl_FragColor = texture2D(tex_sampler_0, new_coord);\n" + |
| "}\n"; |
| |
| public FisheyeFilter(String name) { |
| super(name); |
| } |
| |
| @Override |
| public void setupPorts() { |
| addMaskedInputPort("image", ImageFormat.create(ImageFormat.COLORSPACE_RGBA)); |
| addOutputBasedOnInput("image", "image"); |
| } |
| |
| @Override |
| public FrameFormat getOutputFormat(String portName, FrameFormat inputFormat) { |
| return inputFormat; |
| } |
| |
| public void initProgram(FilterContext context, int target) { |
| switch (target) { |
| case FrameFormat.TARGET_GPU: |
| ShaderProgram shaderProgram = new ShaderProgram(context, mFisheyeShader); |
| shaderProgram.setMaximumTileSize(mTileSize); |
| mProgram = shaderProgram; |
| break; |
| |
| default: |
| throw new RuntimeException("Filter FisheyeFilter does not support frames of " + |
| "target " + target + "!"); |
| } |
| mTarget = target; |
| } |
| |
| @Override |
| public void process(FilterContext context) { |
| // Get input frame |
| Frame input = pullInput("image"); |
| FrameFormat inputFormat = input.getFormat(); |
| |
| // Create output frame |
| Frame output = context.getFrameManager().newFrame(inputFormat); |
| |
| // Create program if not created already |
| if (mProgram == null || inputFormat.getTarget() != mTarget) { |
| initProgram(context, inputFormat.getTarget()); |
| } |
| |
| // Check if the frame size has changed |
| if (inputFormat.getWidth() != mWidth || inputFormat.getHeight() != mHeight) { |
| updateFrameSize(inputFormat.getWidth(), inputFormat.getHeight()); |
| } |
| |
| // Process |
| mProgram.process(input, output); |
| |
| // Push output |
| pushOutput("image", output); |
| |
| // Release pushed frame |
| output.release(); |
| } |
| |
| @Override |
| public void fieldPortValueUpdated(String name, FilterContext context) { |
| if (mProgram != null) { |
| updateProgramParams(); |
| } |
| } |
| |
| private void updateFrameSize(int width, int height) { |
| mWidth = width; |
| mHeight = height; |
| |
| updateProgramParams(); |
| } |
| |
| private void updateProgramParams() { |
| final float pi = 3.14159265f; |
| float scale[] = new float[2]; |
| if (mWidth > mHeight) { |
| scale[0] = 1f; |
| scale[1] = ((float) mHeight) / mWidth; |
| } else { |
| scale[0] = ((float) mWidth) / mHeight; |
| scale[1] = 1f; |
| } |
| float alpha = mScale * 2.0f + 0.75f; |
| float bound2 = 0.25f * (scale[0] * scale[0] + scale[1] * scale[1]); |
| float bound = (float) Math.sqrt(bound2); |
| float radius = 1.15f * bound; |
| float radius2 = radius * radius; |
| float max_radian = 0.5f * pi - |
| (float) Math.atan(alpha / bound * (float) Math.sqrt(radius2 - bound2)); |
| float factor = bound / max_radian; |
| |
| mProgram.setHostValue("scale", scale); |
| mProgram.setHostValue("radius2",radius2); |
| mProgram.setHostValue("factor", factor); |
| mProgram.setHostValue("alpha", alpha); |
| } |
| } |