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 java.util.Date;
  import java.util.Random;
  
  public class LomoishFilter extends Filter {
  
      @GenerateFieldPort(name = "tile_size", hasDefault = true)
      private int mTileSize = 640;
  
      private Program mProgram;
      private Random mRandom;
  
      private int mWidth = 0;
      private int mHeight = 0;
      private int mTarget = FrameFormat.TARGET_UNSPECIFIED;
  
      private final String mLomoishShader =
              "precision mediump float;\n" +
              "uniform sampler2D tex_sampler_0;\n" +
              "uniform vec2 seed;\n" +
              "uniform float stepsizeX;\n" +
              "uniform float stepsizeY;\n" +
              "uniform float stepsize;\n" +
              "uniform vec2 scale;\n" +
              "uniform float inv_max_dist;\n" +
              "varying vec2 v_texcoord;\n" +
              "float rand(vec2 loc) {\n" +
              "  float theta1 = dot(loc, vec2(0.9898, 0.233));\n" +
              "  float theta2 = dot(loc, vec2(12.0, 78.0));\n" +
              "  float value = cos(theta1) * sin(theta2) + sin(theta1) * cos(theta2);\n" +
              // keep value of part1 in range: (2^-14 to 2^14).
              "  float temp = mod(197.0 * value, 1.0) + value;\n" +
              "  float part1 = mod(220.0 * temp, 1.0) + temp;\n" +
              "  float part2 = value * 0.5453;\n" +
              "  float part3 = cos(theta1 + theta2) * 0.43758;\n" +
              "  return fract(part1 + part2 + part3);\n" +
              "}\n" +
              "void main() {\n" +
              // sharpen
              "  vec3 nbr_color = vec3(0.0, 0.0, 0.0);\n" +
              "  vec2 coord;\n" +
              "  vec4 color = texture2D(tex_sampler_0, v_texcoord);\n" +
              "  coord.x = v_texcoord.x - 0.5 * stepsizeX;\n" +
              "  coord.y = v_texcoord.y - stepsizeY;\n" +
              "  nbr_color += texture2D(tex_sampler_0, coord).rgb - color.rgb;\n" +
              "  coord.x = v_texcoord.x - stepsizeX;\n" +
              "  coord.y = v_texcoord.y + 0.5 * stepsizeY;\n" +
              "  nbr_color += texture2D(tex_sampler_0, coord).rgb - color.rgb;\n" +
              "  coord.x = v_texcoord.x + stepsizeX;\n" +
              "  coord.y = v_texcoord.y - 0.5 * stepsizeY;\n" +
              "  nbr_color += texture2D(tex_sampler_0, coord).rgb - color.rgb;\n" +
              "  coord.x = v_texcoord.x + stepsizeX;\n" +
              "  coord.y = v_texcoord.y + 0.5 * stepsizeY;\n" +
              "  nbr_color += texture2D(tex_sampler_0, coord).rgb - color.rgb;\n" +
              "  vec3 s_color = vec3(color.rgb + 0.3 * nbr_color);\n" +
              // cross process
              "  vec3 c_color = vec3(0.0, 0.0, 0.0);\n" +
              "  float value;\n" +
              "  if (s_color.r < 0.5) {\n" +
              "    value = s_color.r;\n" +
              "  } else {\n" +
              "    value = 1.0 - s_color.r;\n" +
              "  }\n" +
              "  float red = 4.0 * value * value * value;\n" +
              "  if (s_color.r < 0.5) {\n" +
              "    c_color.r = red;\n" +
              "  } else {\n" +
              "    c_color.r = 1.0 - red;\n" +
              "  }\n" +
              "  if (s_color.g < 0.5) {\n" +
              "    value = s_color.g;\n" +
              "  } else {\n" +
              "    value = 1.0 - s_color.g;\n" +
              "  }\n" +
              "  float green = 2.0 * value * value;\n" +
              "  if (s_color.g < 0.5) {\n" +
              "    c_color.g = green;\n" +
              "  } else {\n" +
              "    c_color.g = 1.0 - green;\n" +
              "  }\n" +
              "  c_color.b = s_color.b * 0.5 + 0.25;\n" +
              // blackwhite
              "  float dither = rand(v_texcoord + seed);\n" +
              "  vec3 xform = clamp((c_color.rgb - 0.15) * 1.53846, 0.0, 1.0);\n" +
              "  vec3 temp = clamp((color.rgb + stepsize - 0.15) * 1.53846, 0.0, 1.0);\n" +
              "  vec3 bw_color = clamp(xform + (temp - xform) * (dither - 0.5), 0.0, 1.0);\n" +
              // vignette
              "  coord = v_texcoord - vec2(0.5, 0.5);\n" +
              "  float dist = length(coord * scale);\n" +
              "  float lumen = 0.85 / (1.0 + exp((dist * inv_max_dist - 0.73) * 20.0)) + 0.15;\n" +
              "  gl_FragColor = vec4(bw_color * lumen, color.a);\n" +
              "}\n";
  
      public LomoishFilter(String name) {
          super(name);
          mRandom = new Random(new Date().getTime());
      }
  
      @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, mLomoishShader);
                  shaderProgram.setMaximumTileSize(mTileSize);
                  mProgram = shaderProgram;
                  break;
  
              default:
                  throw new RuntimeException("Filter Sharpen does not support frames of " +
                      "target " + target + "!");
          }
          mTarget = target;
      }
  
      private void initParameters() {
          if (mProgram !=null) {
              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 max_dist = ((float) Math.sqrt(scale[0] * scale[0] + scale[1] * scale[1])) * 0.5f;
  
              mProgram.setHostValue("scale", scale);
              mProgram.setHostValue("inv_max_dist", 1.0f / max_dist);
  
              mProgram.setHostValue("stepsize", 1.0f / 255.0f);
              mProgram.setHostValue("stepsizeX", 1.0f / mWidth);
              mProgram.setHostValue("stepsizeY", 1.0f / mHeight);
  
              float seed[] = { mRandom.nextFloat(), mRandom.nextFloat() };
              mProgram.setHostValue("seed", seed);
          }
      }
  
      @Override
      public void process(FilterContext context) {
          // Get input frame
          Frame input = pullInput("image");
          FrameFormat inputFormat = input.getFormat();
  
          // 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();
              initParameters();
          }
  
          // Create output frame
          Frame output = context.getFrameManager().newFrame(inputFormat);
  
          // Process
          mProgram.process(input, output);
  
          // Push output
          pushOutput("image", output);
  
          // Release pushed frame
          output.release();
      }
  }
  