yuvilace.c

/*
**<h3>Interlace Detection</h3>
**<h4>Experimental</h4>
**<p>Attempts to perform interlace detection, by FFT
**the vertical lines in the screen, and averaging the resulting
**frequency spectra.  Also tried experimenting with filtering to
**intelligently remove interlace.
**</p>
**<p> This code simply performs a 1d vertical FFT on the video </p>
**<h4>Theory</h4>
**<h4>Experiments in interlace detection</h4>
**<ul>
**<li>Interlace is the increase (doubling) of temporal speed at the sacrifice (halving) of vertical spacial information.
**<li>Interlace is totally adaptive.  Stationary objects increase their vertical resolution without any sort of detection.
**<li>This system exploits the persistance of vision in the eye.
**</ul>
 *
**<p>
**  In a full height progressive display, if the frame is treated as occuring at the same temporal value, stationary images
**  retain their full height resolution, however moving images suffer from "comb" effect
**</p>
**<p>
**  If the entire frame is treated as two separate temporal images, then the vertical resolution is halved.
**  A full height frame can be produced by interpolation, however this is noticable and would needlessly degrade the
**  the image.
**  Stationary portions would lose information.  Moving portions have already lost information due to the
**  nature of interlace.
**</p>
**<p>
**  Neither case is true, as part of the image may be stationary and part may be moving.
**  Detecting the moving portion and interpolating only the needed pixels is the goal of this code.
**</p>
 *
 *  modified from yuvfps.c by
 *  Copyright (C) 2002 Alfonso Garcia-Patiño Barbolani
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *

 gcc yuvilace.c -I/sw/include -I/sw/include/mjpegtools -L/sw/lib -lfftw3 -lmjpegutils -o yuvilace

 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <sys/types.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <fftw3.h>
#include <math.h>

#include "yuv4mpeg.h"
#include "mpegconsts.h"
#include "utilyuv.h"

#define YUVRFPS_VERSION "0.1"

static void print_usage()
{
	fprintf (stderr,
			 "usage: yuvilace [-v -h -Ip|b|p]\n"
			 "\n"
			 "\t -v Verbosity degree : 0=quiet, 1=normal, 2=verbose/debug\n"
			 "\t -I<pbt> Force interlace mode\n"
			 "\t -h print this help\n"
			 );
}


static void filterpixel(uint8_t *o, uint8_t *p, int i, int j, int w, int h) {

	int t;

	if (j<h-1){
		t = abs(p[i+j*w] - p[i+(j+1)*w]) + 16;
		//t = t<0?0:t;
		o[i+j*w] = t>255?255:t;
	} else {
		o[i+j*w] = p[i+j*w];
	}
}

static void filterframe (uint8_t *m[3], uint8_t *n[3], y4m_stream_info_t *si)
{

	int x,y;
	int height,width,height2,width2;

	height=y4m_si_get_plane_height(si,0);
	width=y4m_si_get_plane_width(si,0);

	// I'll assume that the chroma subsampling is the same for both u and v channels
	height2=y4m_si_get_plane_height(si,1);
	width2=y4m_si_get_plane_width(si,1);


	for (y=0; y < height; y++) {
		for (x=0; x < width; x++) {

			filterpixel(m[0],n[0],x,y,width,height);

			if (x<width2 && y<height2) {
				filterpixel(m[1],n[1],x,y,width2,height2);
				filterpixel(m[2],n[2],x,y,width2,height2);
			}

		}
	}

}



static void vertdiff(  int fdIn  , y4m_stream_info_t  *inStrInfo, int fdOut, y4m_stream_info_t  *outStrInfo)
{
	y4m_frame_info_t   in_frame ;
	uint8_t            *yuv_data[3],*yuv_odata[3] ;
	int                read_error_code ;
	int                write_error_code ;

	// Allocate memory for the YUV channels

	if (chromalloc(yuv_data,inStrInfo))
		mjpeg_error_exit1 ("Could'nt allocate memory for the YUV4MPEG data!");

	if (chromalloc(yuv_odata,inStrInfo))
		mjpeg_error_exit1 ("Could'nt allocate memory for the YUV4MPEG data!");


	/* Initialize counters */

	write_error_code = Y4M_OK ;

	y4m_init_frame_info( &in_frame );
	read_error_code = y4m_read_frame(fdIn, inStrInfo,&in_frame,yuv_data );

	while( Y4M_ERR_EOF != read_error_code && write_error_code == Y4M_OK ) {

		// do work
		if (read_error_code == Y4M_OK) {
			filterframe(yuv_odata,yuv_data,inStrInfo);
			write_error_code = y4m_write_frame( fdOut, inStrInfo, &in_frame, yuv_odata );
		}

		y4m_fini_frame_info( &in_frame );
		y4m_init_frame_info( &in_frame );
		read_error_code = y4m_read_frame(fdIn, inStrInfo,&in_frame,yuv_data );
	}
	// Clean-up regardless an error happened or not
	y4m_fini_frame_info( &in_frame );

	free( yuv_data[0] );
	free( yuv_data[1] );
	free( yuv_data[2] );

	free( yuv_odata[0] );
	free( yuv_odata[1] );
	free( yuv_odata[2] );



	if( read_error_code != Y4M_ERR_EOF )
		mjpeg_error_exit1 ("Error reading from input stream!");

}


static void detect(  int fdIn , y4m_stream_info_t  *inStrInfo,
				   int fdOut, y4m_stream_info_t  *outStrInfo)
{
	y4m_frame_info_t   in_frame ;
	uint8_t            *yuv_data[3],*yuv_odata[3];

	int                frame_data_size ;
	int                read_error_code ;
	int                write_error_code ;
	int                src_frame_counter ;
	int l=0,f=0,x,y,w,h;
	int cw,ch;
	int points = 512,window=128;
	double *crdata,*cidata,*rdata = NULL, *idata = NULL;
	fftw_plan rplan, crplan;

	// Allocate memory for the YUV channels
	w = y4m_si_get_width(inStrInfo);
	h =  y4m_si_get_height(inStrInfo);
	cw = y4m_si_get_plane_width(inStrInfo,1);
	ch = y4m_si_get_plane_height(inStrInfo,1);

	// should check for allocation errors here.

	chromalloc(yuv_data,inStrInfo);
	if( !yuv_data[0] || !yuv_data[1] || !yuv_data[2])
		mjpeg_error_exit1 ("Could'nt allocate memory for the YUV4MPEG data!");

	chromalloc(yuv_odata,inStrInfo);
	if( !yuv_odata[0] || !yuv_odata[1] || !yuv_odata[2])
		mjpeg_error_exit1 ("Could'nt allocate memory for the YUV4MPEG data!");

	rdata = (double *)fftw_malloc(w * h * sizeof(double));
	idata = (double *)fftw_malloc(w * h * sizeof(double));

	crdata = (double *)fftw_malloc(w * h * sizeof(double));
	cidata = (double *)fftw_malloc(w * h * sizeof(double));

	// should check for malloc errors
	if( !rdata || !idata )
		mjpeg_error_exit1 ("Could'nt allocate memory for the fft data!");

	write_error_code = Y4M_OK ;

	src_frame_counter = 0 ;

	mjpeg_info("Measuring fftw plan. please wait");

	rplan = fftw_plan_r2r_2d(h,w, rdata, idata, FFTW_R2HC, FFTW_R2HC, FFTW_MEASURE);
	crplan = fftw_plan_r2r_2d(ch,cw, crdata, cidata, FFTW_R2HC, FFTW_R2HC, FFTW_MEASURE);

	mjpeg_info("Measuring done");

	if (rplan==NULL)
		mjpeg_error_exit1("cannot create FFTW plan");

	 memset((void *)idata, 0, w * h * sizeof(double));
//	iplan = fftw_plan_r2r_1d(h, idata, rdata, FFTW_HC2R, FFTW_BACKWARD);

	chromaset(yuv_odata,inStrInfo,16,127,127);

	// initialise and read the first number of frames
	y4m_init_frame_info( &in_frame );
	read_error_code = y4m_read_frame(fdIn,inStrInfo,&in_frame,yuv_data );

	while( Y4M_ERR_EOF != read_error_code && write_error_code == Y4M_OK ) {

		// fft the frame
		// only doing the luma channel

		chromacpy(yuv_odata,yuv_data,inStrInfo);

		// Make a sum of the common vertical frequencies

		for (x=0; x<w; x++) {
			for (y=0; y<h; y++) {
				rdata[y*w+x] = yuv_data[0][y*w+x];
			}
		}

		fftw_execute(rplan);

		for (x=0; x<w; x++) {
			for (y=0; y<h; y++) {
				yuv_odata[0][y*w+x] = abs(idata[y*w+x])/16;
			}
		}

		for (x=0; x<cw; x++) {
			for (y=0; y<ch; y++) {
				crdata[y*cw+x] = yuv_data[1][y*cw+x];
			}
		}

		fftw_execute(crplan);

		for (x=0; x<cw; x++) {
			for (y=0; y<ch; y++) {
				yuv_odata[1][y*cw+x] = abs(cidata[y*cw+x])/16 + 127;
			}
		}

		for (x=0; x<cw; x++) {
			for (y=0; y<ch; y++) {
				crdata[y*cw+x] = yuv_data[2][y*cw+x];
			}
		}

		fftw_execute(crplan);

		for (x=0; x<cw; x++) {
			for (y=0; y<ch; y++) {
				yuv_odata[2][y*cw+x] = abs(cidata[y*cw+x])/16 + 127;
			}
		}


		write_error_code = y4m_write_frame( fdOut, outStrInfo, &in_frame, yuv_odata );
		y4m_fini_frame_info( &in_frame );
		y4m_init_frame_info( &in_frame );
		read_error_code = y4m_read_frame(fdIn,inStrInfo,&in_frame,yuv_data );
		++src_frame_counter ;

	}

	// Clean-up regardless an error happened or not

	y4m_fini_frame_info( &in_frame );

	free( yuv_data[0] );
	free( yuv_data[1] );
	free( yuv_data[2] );
	free( yuv_odata[0] );
	free( yuv_odata[1] );
	free( yuv_odata[2] );

	// output sum of vertical frequency
	//		for (y=0;y<h;y++) printf ("%d %f\n",y,sdata[y]);


	fftw_destroy_plan(rplan);
	fftw_free(rdata);
	fftw_free(idata);


	if( read_error_code != Y4M_ERR_EOF )
		mjpeg_error_exit1 ("Error reading from input stream!");
	if( write_error_code != Y4M_OK )
		mjpeg_error_exit1 ("Error writing output stream!");

}




// *************************************************************************************
// MAIN
// *************************************************************************************
int main (int argc, char *argv[])
{

	int verbose = 4; // LOG_ERROR ;
	int drop_frames = 0;
	int fdIn = 0 ;
	int fdOut = 1 ;
	y4m_stream_info_t in_streaminfo,out_streaminfo;
	int src_interlacing = Y4M_UNKNOWN;
	y4m_ratio_t src_frame_rate;
	const static char *legal_flags = "F:I:v:h";
	int c ;

	while ((c = getopt (argc, argv, legal_flags)) != -1) {
		switch (c) {
			case 'v':
				verbose = atoi (optarg);
				if (verbose < 0 || verbose > 2)
					mjpeg_error_exit1 ("Verbose level must be [0..2]");
				break;
			case 'I':
				src_interlacing = parse_interlacing(optarg);
				break;
			case 'F':
				drop_frames = atoi(optarg);
				break;
			case 'h':
			case '?':
				print_usage (argv);
				return 0 ;
				break;
		}
	}


	// mjpeg tools global initialisations
	mjpeg_default_handler_verbosity (verbose);

	// Initialize input streams
	y4m_init_stream_info (&in_streaminfo);
	y4m_init_stream_info (&out_streaminfo);

	// ***************************************************************
	// Get video stream informations (size, framerate, interlacing, aspect ratio).
	// The streaminfo structure is filled in
	// ***************************************************************
	// INPUT comes from stdin, we check for a correct file header
	y4m_accept_extensions(1);
	if (y4m_read_stream_header (fdIn, &in_streaminfo) != Y4M_OK)
		mjpeg_error_exit1 ("Could'nt read YUV4MPEG header!");

	src_frame_rate = y4m_si_get_framerate( &in_streaminfo );
	y4m_copy_stream_info( &out_streaminfo, &in_streaminfo );


	// Information output
	mjpeg_info ("yuvrfps (version " YUVRFPS_VERSION ") is a frame rate converter which drops doubled frames for yuv streams");
	mjpeg_info ("yuvrfps -h for help, or man yuvaddetect");

	/* in that function we do all the important work */
	y4m_write_stream_header(fdOut,&out_streaminfo);

//	detect( fdIn,&in_streaminfo,fdOut,&out_streaminfo);
	vertdiff(fdIn,&in_streaminfo,fdOut,&out_streaminfo);

	y4m_fini_stream_info (&in_streaminfo);
	y4m_fini_stream_info (&out_streaminfo);

	return 0;
}
/*
 * Local variables:
 *  tab-width: 8
 *  indent-tabs-mode: nil
 * End:
 */