content: /*
   * 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 android.graphics.Bitmap;
  import android.graphics.Canvas;
  import android.graphics.Color;
  import android.graphics.Paint;
  
  /**
   * @hide
   */
  public class RedEyeFilter extends Filter {
  
      private static final float RADIUS_RATIO = 0.06f;
      private static final float MIN_RADIUS = 10.0f;
      private static final float DEFAULT_RED_INTENSITY = 1.30f;
  
      @GenerateFieldPort(name = "centers")
      private float[] mCenters;
  
      @GenerateFieldPort(name = "tile_size", hasDefault = true)
      private int mTileSize = 640;
  
      private Frame mRedEyeFrame;
      private Bitmap mRedEyeBitmap;
  
      private final Canvas mCanvas = new Canvas();
      private final Paint mPaint = new Paint();
  
      private float mRadius;
  
      private int mWidth = 0;
      private int mHeight = 0;
  
      private Program mProgram;
      private int mTarget = FrameFormat.TARGET_UNSPECIFIED;
  
      private final String mRedEyeShader =
              "precision mediump float;\n" +
              "uniform sampler2D tex_sampler_0;\n" +
              "uniform sampler2D tex_sampler_1;\n" +
              "uniform float intensity;\n" +
              "varying vec2 v_texcoord;\n" +
              "void main() {\n" +
              "  vec4 color = texture2D(tex_sampler_0, v_texcoord);\n" +
              "  vec4 mask = texture2D(tex_sampler_1, v_texcoord);\n" +
              "  if (mask.a > 0.0) {\n" +
              "    float green_blue = color.g + color.b;\n" +
              "    float red_intensity = color.r / green_blue;\n" +
              "    if (red_intensity > intensity) {\n" +
              "      color.r = 0.5 * green_blue;\n" +
              "    }\n" +
              "  }\n" +
              "  gl_FragColor = color;\n" +
              "}\n";
  
      public RedEyeFilter(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, mRedEyeShader);
                  shaderProgram.setMaximumTileSize(mTileSize);
                  mProgram = shaderProgram;
                  mProgram.setHostValue("intensity", DEFAULT_RED_INTENSITY);
                  break;
              default:
                  throw new RuntimeException("Filter RedEye 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) {
              mWidth = inputFormat.getWidth();
              mHeight = inputFormat.getHeight();
          }
          createRedEyeFrame(context);
  
          // Process
          Frame[] inputs = {input, mRedEyeFrame};
          mProgram.process(inputs, output);
  
          // Push output
          pushOutput("image", output);
  
          // Release pushed frame
          output.release();
  
          // Release unused frame
          mRedEyeFrame.release();
          mRedEyeFrame = null;
      }
  
      @Override
      public void fieldPortValueUpdated(String name, FilterContext context) {
           if (mProgram != null) {
              updateProgramParams();
          }
      }
  
      private void createRedEyeFrame(FilterContext context) {
          int bitmapWidth = mWidth / 2;
          int bitmapHeight = mHeight / 2;
  
          Bitmap redEyeBitmap = Bitmap.createBitmap(bitmapWidth, bitmapHeight, Bitmap.Config.ARGB_8888);
          mCanvas.setBitmap(redEyeBitmap);
          mPaint.setColor(Color.WHITE);
          mRadius = Math.max(MIN_RADIUS, RADIUS_RATIO * Math.min(bitmapWidth, bitmapHeight));
  
          for (int i = 0; i < mCenters.length; i += 2) {
              mCanvas.drawCircle(mCenters[i] * bitmapWidth, mCenters[i + 1] * bitmapHeight,
                                 mRadius, mPaint);
          }
  
          FrameFormat format = ImageFormat.create(bitmapWidth, bitmapHeight,
                                                  ImageFormat.COLORSPACE_RGBA,
                                                  FrameFormat.TARGET_GPU);
          mRedEyeFrame = context.getFrameManager().newFrame(format);
          mRedEyeFrame.setBitmap(redEyeBitmap);
          redEyeBitmap.recycle();
      }
  
      private void updateProgramParams() {
          if ( mCenters.length % 2 == 1) {
              throw new RuntimeException("The size of center array must be even.");
          }
      }
  }
  