package org.jcodec.scale;

import org.jcodec.common.model.Picture;

public class Yuv444jToYuv420j implements Transform {
  public void transform(Picture src, Picture dst) {
    int size = src.getWidth() * src.getHeight();
    System.arraycopy(src.getPlaneData(0), 0, dst.getPlaneData(0), 0, size);
    for (int plane = 1; plane < 3; plane++) {
      byte[] srcPl = src.getPlaneData(plane);
      byte[] dstPl = dst.getPlaneData(plane);
      int srcStride = src.getPlaneWidth(plane);
      for (int y = 0, srcOff = 0, dstOff = 0; y < src.getHeight(); y += 2, srcOff += srcStride) {
        for (int x = 0; x < src.getWidth(); x += 2, srcOff += 2, dstOff++)
          dstPl[dstOff] = (byte)(srcPl[srcOff] + srcPl[srcOff + 1] + srcPl[srcOff + srcStride] + srcPl[srcOff + srcStride + 1] + 2 >> 2); 
      } 
    } 
  }
}