greedy.c

来自「linux下的MPEG1」· C语言 代码 · 共 205 行

/**
 * Copyright (c) 2000 Tom Barry  All rights reserved.
 * mmx.h port copyright (c) 2002 Billy Biggs <[e-mail]>.
 *
 * This code is ported from DScaler: http://deinterlace.sf.net/
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

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

#include <stdio.h>

#if HAVE_INTTYPES_H
#include <inttypes.h>
#else
#include <stdint.h>
#endif

#include "attributes.h"
#include "xineutils.h"
#include "deinterlace.h"
#include "speedtools.h"
#include "speedy.h"
#include "plugins.h"

// This is a simple lightweight DeInterlace method that uses little CPU time
// but gives very good results for low or intermedite motion.
// It defers frames by one field, but that does not seem to produce noticeable
// lip sync problems.
//
// The method used is to take either the older or newer weave pixel depending
// upon which give the smaller comb factor, and then clip to avoid large damage
// when wrong.
//
// I'd intended this to be part of a larger more elaborate method added to 
// Blended Clip but this give too good results for the CPU to ignore here.

static void copy_scanline( uint8_t *output,
                           deinterlace_scanline_data_t *data,
                           int width )
{
    blit_packed422_scanline( output, data->m1, width );
}

static int GreedyMaxComb = 15;

static void deinterlace_greedy_packed422_scanline_mmxext( uint8_t *output,
                                                          deinterlace_scanline_data_t *data,
                                                          int width )
{
#if defined(ARCH_X86) || defined(ARCH_X86_64)
    mmx_t MaxComb;
    uint8_t *m0 = data->m0;
    uint8_t *t1 = data->t1;
    uint8_t *b1 = data->b1;
    uint8_t *m2 = data->m2;

    // How badly do we let it weave? 0-255
    MaxComb.ub[ 0 ] = GreedyMaxComb;
    MaxComb.ub[ 1 ] = GreedyMaxComb;
    MaxComb.ub[ 2 ] = GreedyMaxComb;
    MaxComb.ub[ 3 ] = GreedyMaxComb;
    MaxComb.ub[ 4 ] = GreedyMaxComb;
    MaxComb.ub[ 5 ] = GreedyMaxComb;
    MaxComb.ub[ 6 ] = GreedyMaxComb;
    MaxComb.ub[ 7 ] = GreedyMaxComb;

    // L2 == m0
    // L1 == t1
    // L3 == b1
    // LP2 == m2

    width /= 4;
    while( width-- ) {
        movq_m2r( *t1, mm1 );    // L1
        movq_m2r( *m0, mm2 );    // L2
        movq_m2r( *b1, mm3 );    // L3
        movq_m2r( *m2, mm0 );    // LP2

        // average L1 and L3 leave result in mm4
        movq_r2r( mm1, mm4 );    // L1
        pavgb_r2r( mm3, mm4 );   // (L1 + L3)/2


        // get abs value of possible L2 comb
        movq_r2r( mm2, mm7 );    // L2
        psubusb_r2r( mm4, mm7 ); // L2 - avg
        movq_r2r( mm4, mm5 );    // avg
        psubusb_r2r( mm2, mm5 ); // avg - L2
        por_r2r( mm7, mm5 );     // abs(avg-L2)
        movq_r2r( mm4, mm6 );    // copy of avg for later


        // get abs value of possible LP2 comb
        movq_r2r( mm0, mm7 );    // LP2
        psubusb_r2r( mm4, mm7 ); // LP2 - avg
        psubusb_r2r( mm0, mm4 ); // avg - LP2
        por_r2r( mm7, mm4 );     // abs(avg-LP2)

        // use L2 or LP2 depending upon which makes smaller comb
        psubusb_r2r( mm5, mm4 ); // see if it goes to zero
        psubusb_r2r( mm5, mm5 ); // 0
        pcmpeqb_r2r( mm5, mm4 ); // if (mm4=0) then FF else 0
        pcmpeqb_r2r( mm4, mm5 ); // opposite of mm4

        // if Comb(LP2) <= Comb(L2) then mm4=ff, mm5=0 else mm4=0, mm5 = 55
        pand_r2r( mm2, mm5 );    // use L2 if mm5 == ff, else 0
        pand_r2r( mm0, mm4 );    // use LP2 if mm4 = ff, else 0
        por_r2r( mm5, mm4 );     // may the best win

        // Now lets clip our chosen value to be not outside of the range
        // of the high/low range L1-L3 by more than abs(L1-L3)
        // This allows some comb but limits the damages and also allows more
        // detail than a boring oversmoothed clip.

        movq_r2r( mm1, mm2 );    // copy L1
        psubusb_r2r( mm3, mm2 ); // - L3, with saturation
        paddusb_r2r( mm3, mm2 ); // now = Max(L1,L3)

        pcmpeqb_r2r( mm7, mm7 ); // all ffffffff
        psubusb_r2r( mm1, mm7 ); // - L1 
        paddusb_r2r( mm7, mm3 ); // add, may sat at fff..
        psubusb_r2r( mm7, mm3 ); // now = Min(L1,L3)

        // allow the value to be above the high or below the low by amt of MaxComb
        paddusb_m2r( MaxComb, mm2 );    // increase max by diff
        psubusb_m2r( MaxComb, mm3 );    // lower min by diff

        psubusb_r2r( mm3, mm4 );        // best - Min
        paddusb_r2r( mm3, mm4 );        // now = Max(best,Min(L1,L3)

        pcmpeqb_r2r( mm7, mm7 );        // all ffffffff
        psubusb_r2r( mm4, mm7 );        // - Max(best,Min(best,L3) 
        paddusb_r2r( mm7, mm2 );        // add may sat at FFF..
        psubusb_r2r( mm7, mm2 );        // now = Min( Max(best, Min(L1,L3), L2 )=L2 clipped

        movntq_r2m( mm2, *output );     // move in our clipped best

        // Advance to the next set of pixels.
        output += 8;
        m0 += 8;
        t1 += 8;
        b1 += 8;
        m2 += 8;
    }
    sfence();
    emms();
#endif
}

/**
 * The greedy deinterlacer introduces a one-field delay on the input.
 * From the diagrams in deinterlace.h, the field being deinterlaced is
 * always t-1.  For this reason, our copy_scanline method is used for
 * deinterlace_method_t's interpolate_scanline function, and the real
 * work is done in deinterlace_method_t's copy_scanline function.
 */

static deinterlace_method_t greedymethod =
{
    "Greedy - Low motion (DScaler)",
    "Greedy",
/*
    "Motion Adaptive: Simple Detection",
    "AdaptiveSimple",
*/
    3,
    MM_ACCEL_X86_MMXEXT,
    0,
    1,
    copy_scanline,
    deinterlace_greedy_packed422_scanline_mmxext,
    0,
    1,
    "Uses heuristics to detect motion in the input frames and reconstruct "
    "image detail where possible.  Use this for high quality output even "
    "on monitors set to an arbitrary refresh rate.\n"
    "\n"
    "Simple detection uses linear interpolation where motion is detected, "
    "using a two-field buffer.  This is the Greedy: Low Motion deinterlacer "
    "from DScaler."
};

deinterlace_method_t *greedy_get_method( void )
{
    return &greedymethod;
}