//
// EFP_Average.C
//
// $Id: EFP_Average.C,v 1.4 1998/10/14 21:25:55 mmp Exp $
//

/* A simple plug-in that returns the image that is an average of
   two input images */

#include "EF.h"
#include <stdio.h>
#include <string.h>

extern "C" {
  void averageImages(EF_Image *image, EF_Image *im, EF_Image *outim, float);
  void pluginInit(EF_PluginOptions *options);
	   }

/* This is called when the plug-in is loaded by the video editor. 
   We register the plug-in with the editor by filling in the options
   structure */

void pluginInit(EF_PluginOptions *options)
{
    options->applyTwo = averageImages;
    strcpy(options->name,"Average");
}

void averageImages(EF_Image *image1, EF_Image *image2,
		   EF_Image *result, float)
{
    /* Loop over all of the pixels in each image */
    for(int y = 0; y < image1->ySize; y++) {
	for (int x = 0; x < image1->xSize; x++) {
	    /* Get the pixel from each image */
	    long pix1 = EF_ImageXY(image1, x, y);
	    long pix2 = EF_ImageXY(image2, x, y);
	    long pixAvg;
	    
	    /* Compute the average of each component */
	    RED(pixAvg) = (RED(pix1) + RED(pix2)) / 2;
	    GREEN(pixAvg) = (GREEN(pix1) + GREEN(pix2)) / 2;
	    BLUE(pixAvg) = (BLUE(pix1) + BLUE(pix2)) / 2;
	    ALPHA(pixAvg) = (ALPHA(pix1) + ALPHA(pix2)) / 2;

	    /* Set the corresponding pixel in the result image
	       with the average pixel */
	    EF_ImageXY(result, x, y)= pixAvg;
	}
    }
}