package org.jcodec.scale;

import org.jcodec.common.model.ColorSpace;
import org.jcodec.common.model.Picture;

public class RgbToBgr implements Transform {
  public void transform(Picture src, Picture dst) {
    if ((src.getColor() != ColorSpace.RGB && src.getColor() != ColorSpace.BGR) || (
      dst.getColor() != ColorSpace.RGB && dst.getColor() != ColorSpace.BGR))
      throw new IllegalArgumentException("Expected RGB or BGR inputs, was: " + 
          String.valueOf(src.getColor()) + ", " + String.valueOf(dst.getColor())); 
    byte[] dataSrc = src.getPlaneData(0);
    byte[] dataDst = dst.getPlaneData(0);
    for (int i = 0; i < dataSrc.length; i += 3) {
      byte tmp = dataSrc[i + 2];
      dataDst[i + 2] = dataSrc[i];
      dataDst[i] = tmp;
      dataDst[i + 1] = dataSrc[i + 1];
    } 
  }
}